ALBERT

Description: 〈h3〉Abstract〈/h3〉 〈p〉We show that the Hawking temperature is modified in the presence of dark energy in an emergent gravity scenario for Kerr–Newman(KN) and Kerr–Newman–AdS(KNAdS) background metrics. The emergent gravity metric is not conformally equivalent to the gravitational metric. We calculate the Hawking temperatures for these emergent gravity metrics along 〈span〉 〈span〉\(\theta =0\)〈/span〉 〈/span〉. Also we show that the emergent black hole metrics are satisfying Einstein’s equations for large 〈em〉r〈/em〉 and 〈span〉 〈span〉\(\theta =0\)〈/span〉 〈/span〉. Our analysis is done in the context of dark energy in an emergent gravity scenario having 〈span〉 〈span〉\(k-\)〈/span〉 〈/span〉essence scalar fields 〈span〉 〈span〉\(\phi \)〈/span〉 〈/span〉 with a Dirac–Born–Infeld type Lagrangian. In KN and KNAdS background, the scalar field 〈span〉 〈span〉\(\phi (r,t)=\phi _{1}(r)+\phi _{2}(t)\)〈/span〉 〈/span〉 satisfies the emergent gravity equations of motion at 〈span〉 〈span〉\(r\rightarrow \infty \)〈/span〉 〈/span〉 for 〈span〉 〈span〉\(\theta =0\)〈/span〉 〈/span〉.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉We present a new way of performing hypothesis tests on scattering data, by means of a perturbatively calculable classifier. This classifier exploits the “history tree” of how the measured data point might have evolved out of any simpler (reconstructed) points along classical paths, while explicitly keeping quantum–mechanical interference effects by copiously employing complete leading-order matrix elements. This approach extends the standard Matrix Element Method to an arbitrary number of final state objects and to exclusive final states where reconstructed objects can be collinear or soft. We have implemented this method into the standalone package 〈span〉hytrees〈/span〉 and have applied it to Higgs boson production in association with two jets, with subsequent decay into photons. 〈span〉hytrees〈/span〉 allows to construct an optimal classifier to discriminate this process from large Standard Model backgrounds. It further allows to find the most sensitive kinematic regions that contribute to the classification.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉We investigate the dimensional dependence (〈em〉D〈/em〉-dependence) of the difference (gap) between the critical temperatures associated with the uniform/non-uniform and non-uniform/gapped transitions in the large-〈em〉N〈/em〉 bosonic gauge theories with 〈em〉D〈/em〉 matrix scalar fields on a 〈span〉 〈span〉\(S^1\)〈/span〉 〈/span〉-circled space. We use the equations describing these critical temperatures given in the 1/〈em〉D〈/em〉 expansion Mandal et al. (JHEP 1002:034, 〈span〉2010〈/span〉). These transitions are related with the Gregory-Laflamme instabilities in the gravities and the Rayleigh-Plateau instabilities in the fluid dynamics, and qualitative similarities between these are expected. We find that the tendency in the 〈em〉D〈/em〉-dependence of the gap is opposite from those in the gravity and fluid side. This is interesting as a counterexample to the gauge/gravity and gauge/fluid correspondences.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉We consider the four-fermion Lifshitz model, introduce in this model an auxiliary vector field, and generate an effective dynamics for this field. We explicitly demonstrate that within this dynamics, the effective bumblebee potential for the vector field naturally arises as a one-loop correction and allows for the dynamical breaking of the rotational symmetry.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉We employ an effective field theory to study the detectability of sub-GeV dark matter through its interaction with the gapless excitations of superfluid 〈span〉 〈span〉\(^4\)〈/span〉 〈/span〉He. In a quantum field theory language, the possible interactions between the dark matter and the superfluid phonon are solely dictated by symmetry. We compute the rate for the emission of one and two phonons, and show that these two observables combined allow for a large exclusion region for the dark matter masses. Our approach allows a direct calculation of the differential distributions, even though it is limited only to the region of softer phonon excitations, where the effective field theory is well defined. The method presented here is easily extendible to different models of dark matter.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉We investigate a simplified model of the strange stars in the framework of Finslerian geometry, composed of charged fluid. It is considered that the fluid consisting of three flavor quarks including a small amount of non-interacting electrons to maintain the chemical equilibrium and assumed that the fluid is compressible by nature. To obtain the simplified form of the charged strange star we have considered constant flag curvature. Based on geometry, we have developed the field equations within the localized charge distribution. We consider that the strange quarks distributed within the stellar system are complied with the MIT bag model type of equation of state (EOS) and the charge distribution within the system follows a power law. We represent the exterior spacetime by the Finslerian Ressiner-Nordström space-time. The maximum anisotropic stress is obtained at the surface of the system. Whether the system is in equilibrium or not, has been examined with respect to the Tolman–Oppenheimer–Volkoff (TOV) equation, Herrera cracking concept, different energy conditions and adiabatic index. We obtain that the total charge is of the order of 〈span〉 〈span〉\(10^{20}\hbox { C}\)〈/span〉 〈/span〉 and the corresponding electric field is of around 〈span〉 〈span〉\(10^{22}\hbox { V/m}\)〈/span〉 〈/span〉. The central density and central pressure vary inversely with the charge. Varying the free parameter (charge constant) of the model, we find the generalized mass-radius variation of strange stars and determine the maximum limited mass with the corresponding radius. Furthermore, we also considered the variation of mass and radius against central density respectively.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉The universal lower bound of the ratio of shear viscosity to entropy density is suggested by the string theory and gauge duality for any matter. We examined the ratio of shear viscosity to entropy density for viscous accretion flow towards a central gravitating object in the presence of dark energy. The ratio appears close to the universal lower bound for certain optically thin, hot accretion flows as they are embedded by strong magnetic field. Dark energy is a kind of exotic matter which has negative pressure. So dark energy creates repulsive force between the accreting particles, which indicates that shear viscosity of the flow becomes very low. Dark energy as accreting fluid has very high entropy density. The ratio should reach near to the lowest value for dark energy accretion. We wish to study what happens to the shear viscosity to entropy density ratio for viscous dark energy accretion flow.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉An unified cosmological model for an Universe filled with a mass dimension one (MDO) fermionic field plus the standard matter fields is considered. After a primordial quantum fluctuation the field slowly rolls down to the bottom of a symmetry breaking potential, driving the Universe to an inflationary regime that increases the scale factor for about 71 e-folds. After the end of inflation, the field starts to oscillate and can transfer its energy to the standard model particles through a reheating mechanism. Such a process is briefly discussed in terms of the admissible couplings of the MDO field with the electromagnetic and Higgs fields. We show that even if the field loses all its kinetic energy during reheating, it can evolve as dark matter due a gravitational coupling (of spinorial origin) with baryonic matter. Since the field acquires a constant value at the bottom of the potential, a non-null, although tiny, mass term acts as a dark energy component nowadays. Therefore, we conclude that MDO fermionic field is a good candidate to drive the whole evolution of the Universe, in such a way that the inflationary field, dark matter and dark energy are described by different manifestations of a single field.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉We investigate the long-distance, low-energy, leading quantum corrections to gravitational potential for scalarized neutron star (NS) binary systems, by treating general relativity as an effective field theory. We neglect the extended scales of two star components and treat them as heavy point particles, which gravitationally interact with each other via the exchanges of both gravitons and scalar particles, because of the settled scalar configurations inside the stars. Accordingly, the gravitational potential includes both Newtonian potential and scalar-modified Newtonian-like part. We, in the non-relativistic limit, calculate the non-analytic corrections to the modified gravitational potential directly from the sum of all exchanges of both gravitons and scalar particles to one-loop order. The appropriate vertex rules are extracted from the effective Lagrangian. Our calculations demonstrate that either the graviton exchanges or the exchanges of scalar particles contribute to both classical relativistic corrections and quantum corrections to the gravitational potential of the scalarized NS binaries.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉We study the implications of single leptoquark extensions of the Standard Model (SM) under the assumption that their enhanced Yukawa sectors are invariant under global Abelian flavour symmetries already present in SM mass terms. Such symmetries, assumed to be the ‘residual’ subgroups of an ultra-violet flavour theory, have previously been considered in order to predict fermionic mixing angles. Here we focus instead on their effect on the novel flavour structures sourced by the leptoquark representations that address the present 〈span〉 〈span〉\({R}_{K^{(\star )}}\)〈/span〉 〈/span〉 anomalies in semileptonic rare 〈em〉B〈/em〉-decays. Combined with existing flavour data, the residual symmetries prove to be extremely constraining; we find that the (quark-lepton) leptoquark Yukawa couplings fall within 〈span〉 〈span〉\(\mathcal {O}(10)\)〈/span〉 〈/span〉 highly predictive patterns, each with only a single free parameter, when ‘normal’ (SM-like) hierarchies are assumed. In addition, proton decay for the scalar SU(2) triplet representation is naturally avoided in the residual symmetry approach without relying on further model building. Our results indicate that a simultaneous explanation for the 〈span〉 〈span〉\({R}_{K^{(\star )}}\)〈/span〉 〈/span〉 anomalies and the flavour puzzle may be achieved in a simplified, model-independent formalism.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉The main object of the present paper is to investigate the Dirac equation (Dirac fermions) in presence of scalar and vector potential in a class of flat Gödel-type space-time called Som–Raychaudhuri space-time by using the methods quasi-exactly solvable (QES) differential equations and the Nikiforov Uvarov (NU) form. In addition, we evaluate the Einstein, and the Papapetrou.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉We present a dynamical (composite) axion model where the Peccei–Quinn (PQ) symmetry arises automatically as a consequence of chirality and gauge symmetry. The Standard Model is simply extended by a confining and chiral 〈em〉SU〈/em〉(5) gauge symmetry. The PQ symmetry coincides with a 〈span〉 〈span〉\(B-L\)〈/span〉 〈/span〉 symmetry of the exotic sector. The theory is protected by construction from quantum gravitational corrections stemming from operators with mass dimension lower than nine.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉In this work, we investigate the behaviour of Dirac particles in a class of Gödel-type space-time backgrounds in the presence of non-minimal coupling of the gravitational field with background curvature. We obtain the allowed energies for this relativistic system by solving analytically the Dirac equation in flat and curved space in a topologically trivial flat Gödel-type metric, and analyze the effects on the energy eiegnvalues.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉In this paper we consider a special case of vacuum nonlinear electrodynamics with a stress–energy tensor conformal to the Maxwell theory. Distinctive features of this model are the absence of a dimensional parameter for the nonlinearity description and a very simple form of the dominant energy condition, which can easily be verified in an arbitrary pseudo-Riemannian space-time with the consequent constraints on the model parameters. In this paper we analyze some properties of astrophysical compact objects coupled to conformal vacuum nonlinear electrodynamics.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉We study half-BPS surface operators in four dimensional 〈span〉 〈span〉\({{{\mathcal {N}}}}=2\)〈/span〉 〈/span〉 SU(〈em〉N〈/em〉) gauge theories, and analyze their low-energy effective action on the four dimensional Coulomb branch using equivariant localization. We also study surface operators as coupled 2d/4d quiver gauge theories with an SU(〈em〉N〈/em〉) flavour symmetry. In this description, the same surface operator can be described by different quivers that are related to each other by two dimensional Seiberg duality. We argue that these dual quivers correspond, on the localization side, to distinct integration contours that can be determined by the Fayet-Iliopoulos parameters of the two dimensional gauge nodes. We verify the proposal by mapping the solutions of the twisted chiral ring equations of the 2d/4d quivers onto individual residues of the localization integrand.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉The exclusive photoproduction of 〈span〉 〈span〉\(\mathrm {\Upsilon }\mathrm {(nS)} \)〈/span〉 〈/span〉 meson states from protons, 〈span〉 〈span〉\(\gamma \mathrm {p} \rightarrow \mathrm {\Upsilon }\mathrm {(nS)} \,\mathrm {p}\)〈/span〉 〈/span〉 (with 〈span〉 〈span〉\(\mathrm {n}=1,2,3\)〈/span〉 〈/span〉), is studied in ultraperipheral 〈span〉 〈span〉\(\mathrm {p}\)〈/span〉 〈/span〉Pb collisions at a centre-of-mass energy per nucleon pair of 〈span〉 〈span〉\(\sqrt{\smash [b]{s_{_{\mathrm {NN}}}}} = 5.02\,\text {TeV} \)〈/span〉 〈/span〉. The measurement is performed using the 〈span〉 〈span〉\(\mathrm {\Upsilon }\mathrm {(nS)} \rightarrow \mu ^+\mu ^-\)〈/span〉 〈/span〉 decay mode, with data collected by the CMS experiment corresponding to an integrated luminosity of 32.6〈span〉 〈span〉\(\,\text {nb}^{-1}\)〈/span〉 〈/span〉. Differential cross sections as functions of the 〈span〉 〈span〉\(\mathrm {\Upsilon }\mathrm {(nS)} \)〈/span〉 〈/span〉 transverse momentum squared 〈span〉 〈span〉\(p_{\mathrm {T}} ^2\)〈/span〉 〈/span〉, and rapidity 〈em〉y〈/em〉, are presented. The 〈span〉 〈span〉\(\mathrm {\Upsilon (1S)}\)〈/span〉 〈/span〉 photoproduction cross section is extracted in the rapidity range 〈span〉 〈span〉\(|y |〈 2.2\)〈/span〉 〈/span〉, which corresponds to photon–proton centre-of-mass energies in the range 〈span〉 〈span〉\(91〈W_{\gamma \mathrm {p}} 〈826\,\text {GeV} \)〈/span〉 〈/span〉. The data are compared to theoretical predictions based on perturbative quantum chromodynamics and to previous measurements.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉The non-equilibrium early time evolution of an ultra-relativistic heavy ion collision is often described by classical lattice Yang–Mills theory, starting from the colour glass condensate (CGC) effective theory with an anisotropic energy momentum tensor as initial condition. In this work we investigate the systematics associated with such studies and their dependence on various model parameters (IR, UV cutoffs and the amplitude of quantum fluctuations) which are not yet fixed by experiment. We perform calculations for SU(〈span〉 〈span〉\(2\)〈/span〉 〈/span〉) and SU(〈span〉 〈span〉\(3\)〈/span〉 〈/span〉), both in a static box and in an expanding geometry. Generally, the dependence on model parameters is found to be much larger than that on technical parameters like the number of colours, boundary conditions or the lattice spacing. In a static box, all setups lead to isotropisation through chromo-Weibel instabilities, which is illustrated by the accompanying filamentation of the energy density. However, the associated time scale depends strongly on the model parameters and in all cases is longer than the phenomenologically expected one. In the expanding system, no isotropisation is observed for any parameter choice. We show how investigations at fixed initial energy density can be used to better constrain some of the model parameters.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉In this paper we consider a specific type of the bimetric theory of gravitation with the two different metrics introduced in the cosmological frame. Both metrics respect all the symmetries of the standard FLRW solution and contain conformally related spatial parts. One of the metric is assumed to describe the causal structure for the matter. Another metric defines the causal structure for the gravitational interactions. A crucial point is that the spatial part of the metric describing gravity is given by the spatial part of the matter metric conformally rescaled by a time-dependent factor 〈span〉 〈span〉\(\alpha \)〈/span〉 〈/span〉 which, as it turns out, can be linked to the effective gravitational constant and the effective speed of light. In the context of such a bimetric framework we examine the strength of some singular cosmological scenarios in the sense of the criteria introduced by Tipler and Królak. In particular, we show that for the nonsingular scale factor associated with the matter metric, both the vanishing or blowing up of the factor 〈span〉 〈span〉\(\alpha \)〈/span〉 〈/span〉 for some particular moment of the cosmic expansion may lead to a strong singularity with infinite value of the energy density and infinite value of the pressure.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉In this work, we systemically investigate the molecular states from the 〈span〉 〈span〉\(\varSigma ^{(*)}_c{\bar{D}}^{(*)}-\varLambda _c{\bar{D}}^{(*)}\)〈/span〉 〈/span〉 interaction with the help of the Lagrangians with heavy quark and chiral symmetries in a quasipotential Bethe–Salpeter equation (qBSE) approach. The molecular states are produced from isodoublet (I=1/2) 〈span〉 〈span〉\(\varSigma _c{\bar{D}}\)〈/span〉 〈/span〉 interaction with spin parity 〈span〉 〈span〉\(J^P=1/2^-\)〈/span〉 〈/span〉 and 〈span〉 〈span〉\(\varSigma _c{\bar{D}}^*\)〈/span〉 〈/span〉 interaction with 〈span〉 〈span〉\(1/2^-\)〈/span〉 〈/span〉 and 〈span〉 〈span〉\( 3/2^-\)〈/span〉 〈/span〉. Their masses and widths are consistent with the 〈span〉 〈span〉\(P_c(4312)\)〈/span〉 〈/span〉, 〈span〉 〈span〉\(P_c(4440)\)〈/span〉 〈/span〉 and 〈span〉 〈span〉\(P_c(4457)\)〈/span〉 〈/span〉 observed at LHCb. The states, 〈span〉 〈span〉\(\varSigma _c^*{\bar{D}}^*(1/2^-)\)〈/span〉 〈/span〉, 〈span〉 〈span〉\(\varSigma _c^*{\bar{D}}^*(3/2^-)\)〈/span〉 〈/span〉 and 〈span〉 〈span〉\(\varSigma ^*_c{\bar{D}}(3/2^-)\)〈/span〉 〈/span〉, are also produced with the same parameters. The isodoublet 〈span〉 〈span〉\(\varSigma _c^*{\bar{D}}^*\)〈/span〉 〈/span〉 interaction with 〈span〉 〈span〉\(5/2^-\)〈/span〉 〈/span〉, as well as the isoquartet (I=3/2) 〈span〉 〈span〉\(\varSigma _c{\bar{D}}^*\)〈/span〉 〈/span〉 interactions with 〈span〉 〈span〉\(1/2^-\)〈/span〉 〈/span〉 and 〈span〉 〈span〉\(3/2^-\)〈/span〉 〈/span〉, 〈span〉 〈span〉\(\varSigma _c^*{\bar{D}}^*\)〈/span〉 〈/span〉 interaction with 〈span〉 〈span〉\(3/2^-\)〈/span〉 〈/span〉 and 〈span〉 〈span〉\(5/2^-\)〈/span〉 〈/span〉, are also attractive while very large cutoff is required to produce a molecular state. We also investigate the origin of the widths of these molecular states in the same qBSE frame. The 〈span〉 〈span〉\(\varLambda {\bar{D}}^*\)〈/span〉 〈/span〉 channel is dominant in the decays of the states, 〈span〉 〈span〉\(\varSigma _c{\bar{D}}^*(1/2^-)\)〈/span〉 〈/span〉, 〈span〉 〈span〉\(\varSigma _c{\bar{D}}^*(3/2^-)\)〈/span〉 〈/span〉, 〈span〉 〈span〉\(\varSigma _c^*{\bar{D}}(3/2^-)\)〈/span〉 〈/span〉, and 〈span〉 〈span〉\(\varSigma _c{\bar{D}}(1/2^-)\)〈/span〉 〈/span〉. The 〈span〉 〈span〉\(\varSigma ^*_c{\bar{D}}^*(1/2^-)\)〈/span〉 〈/span〉 state has large coupling to 〈span〉 〈span〉\(\varSigma _c{\bar{D}}\)〈/span〉 〈/span〉 channel while the 〈span〉 〈span〉\(\varSigma _c{\bar{D}}^*\)〈/span〉 〈/span〉, 〈span〉 〈span〉\(\varSigma ^*_c{\bar{D}}\)〈/span〉 〈/span〉 and 〈span〉 〈span〉\(\varLambda _c{\bar{D}}^*\)〈/span〉 〈/span〉 channels provide similar contributions to the width of the 〈span〉 〈span〉\(\varSigma ^*_c{\bar{D}}^*(3/2^-)\)〈/span〉 〈/span〉 state. These results will be helpful to understand the current LHCb experimental results, and the three predicted states and the decay pattern of these hidden-charmed molecular pentaquarks can be checked in future experiments.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉A search for new physics in top quark production is performed in proton-proton collisions at 〈span〉 〈span〉\(13\,\text {TeV} \)〈/span〉 〈/span〉. The data set corresponds to an integrated luminosity of 〈span〉 〈span〉\(35.9{\,\text {fb}^{-1}} \)〈/span〉 〈/span〉 collected in 2016 with the CMS detector. Events with two opposite-sign isolated leptons (electrons or muons), and 〈span〉 〈span〉\(\mathrm{b}\)〈/span〉 〈/span〉 quark jets in the final state are selected. The search is sensitive to new physics in top quark pair production and in single top quark production in association with a 〈span〉 〈span〉\(\mathrm{W}\)〈/span〉 〈/span〉 boson. No significant deviation from the standard model expectation is observed. Results are interpreted in the framework of effective field theory and constraints on the relevant effective couplings are set, one at a time, using a dedicated multivariate analysis. This analysis differs from previous searches for new physics in the top quark sector by explicitly separating 〈span〉 〈span〉\(\mathrm{t}\mathrm{W}\)〈/span〉 〈/span〉 from 〈span〉 〈span〉\(\mathrm{t}{\bar{\mathrm{t}}}\)〈/span〉 〈/span〉 events and exploiting the specific sensitivity of the 〈span〉 〈span〉\(\mathrm{t}\mathrm{W}\)〈/span〉 〈/span〉 process to new physics.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉In this work, we present a new class of analytic and well-behaved solution to Einstein’s field equations describing anisotropic matter distribution. It’s achieved in the embedding class one spacetime framework using Karmarkar’s condition. We perform our analysis by proposing a new metric potential 〈span〉 〈span〉\(g_{rr}\)〈/span〉 〈/span〉 which yields us a physically viable performance of all physical variables. The obtained model is representing the physical features of the solution in detail, analytically as well as graphically for strange star candidate SAX J1808.4-3658 (〈span〉 〈span〉\(Mass=0.9 ~M_{\odot }\)〈/span〉 〈/span〉, 〈span〉 〈span〉\(radius=7.951\)〈/span〉 〈/span〉 km), with different values of parameter 〈em〉n〈/em〉 ranging from 0.5 to 3.4. Our suggested solution is free from physical and geometric singularities, satisfies causality condition, Abreu’s criterion and relativistic adiabatic index 〈span〉 〈span〉\(\varGamma \)〈/span〉 〈/span〉, and exhibits well-behaved nature, as well as, all energy conditions and equilibrium condition are well-defined, which implies that our model is physically acceptable. The physical sensitivity of the moment of inertia (〈em〉I〈/em〉) obtained from the solutions is confirmed by the Bejger−Haensel concept, which could provide a precise tool to the matching rigidity of the state equation due to different values of 〈em〉n〈/em〉 viz., 〈span〉 〈span〉\(n=0.5, 1.08, 1.66, 2.24, 2.82\)〈/span〉 〈/span〉 and 3.4.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉We investigate the Casimir effect of the massless scalar field in a cavity formed by ideal parallel plates in the spacetime generated by a rotating axially symmetric distribution of vector or scalar (tensor) unparticles, around which the plates orbit. The presence of the unparticles is incorporated to the background by means of a correction to the Kerr solution of the Einstein equations, in which the characteristic length and the scale dimension associated to the unparticle theory are taken into account. We show that the Casimir energy density depends also on these parameters. The analysis of the “ungravity” limit for the Casimir energy density, in which the characteristic length is very large in comparison to the horizon radius, is made, too. At zero temperature, we show that such a limit implies the instability of the system, since the Casimir energy density becomes an imaginary quantity. The general result is compared to the current terrestrial experiments of the Casimir effect. Thermal corrections also are investigated and the ungravity limit again examined, with the aforementioned instability disappearing at high temperatures.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉Analyses of internal galaxy and cluster dynamics typically employ Newton’s law of gravity, which neglects the field self-interaction effects of General Relativity. This may be why dark matter seems necessary. The universe evolution, on the other hand, is treated with the full theory, General Relativity. However, the approximations of isotropy and homogeneity, normally used to derive and solve the universe evolution equations, effectively suppress General Relativity’s field self-interaction effects and this may introduce the need for dark energy. Calculations have shown that field self-interaction increases the binding of matter inside massive systems, which may account for galaxy and cluster dynamics without invoking dark matter. In turn, energy conservation dictates that the increased binding must be balanced by an effectively decreased gravitational interaction outside the massive system. In this article, such suppression is estimated and its consequence for the Universe’s evolution is discussed. Observations are reproduced without need for dark energy.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉We conjecture explicit evolution formulas for Khovanov polynomials, which for any particular knot are Laurent polynomials of complex variables 〈em〉q〈/em〉 and 〈em〉T〈/em〉, for pretzel knots of genus 〈em〉g〈/em〉 in some regions in the space of winding parameters 〈span〉 〈span〉\(n_0, \dots , n_g\)〈/span〉 〈/span〉. Our description is exhaustive for genera 1 and 2. As previously observed Anokhina and Morozov (2018), Dunin-Barkowski et al. (2019), evolution at 〈span〉 〈span〉\(T\ne -1\)〈/span〉 〈/span〉 is not fully smooth: it switches abruptly at the boundaries between different regions. We reveal that this happens also at the boundary between thin and thick knots, moreover, the thick-knot domain is further stratified. For thin knots the two eigenvalues 1 and 〈span〉 〈span〉\(\lambda = q^2 T\)〈/span〉 〈/span〉, governing the evolution, are the standard 〈em〉T〈/em〉-deformation of the eigenvalues of the 〈em〉R〈/em〉-matrix 1 and 〈span〉 〈span〉\(-q^2\)〈/span〉 〈/span〉. However, in thick knots’ regions extra eigenvalues emerge, and they are powers of the “naive” 〈span〉 〈span〉\(\lambda \)〈/span〉 〈/span〉, namely, they are equal to 〈span〉 〈span〉\(\lambda ^2, \dots , \lambda ^g\)〈/span〉 〈/span〉. From point of view of frequencies, i.e. logarithms of eigenvalues, this is frequency doubling (more precisely, frequency multiplication) – a phenomenon typical for non-linear dynamics. Hence, our observation can signal a hidden non-linearity of superpolynomial evolution. To give this newly observed evolution a short name, note that when 〈span〉 〈span〉\(\lambda \)〈/span〉 〈/span〉 is pure phase the contributions of 〈span〉 〈span〉\(\lambda ^2, \dots , \lambda ^g\)〈/span〉 〈/span〉 oscillate “faster” than the one of 〈span〉 〈span〉\(\lambda \)〈/span〉 〈/span〉. Hence, we call this type of evolution “nimble”.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉Three types of phenomena occurring on both sides of the event horizon of spherically symmetric black holes are analyzed and discussed here. These phenomena are: a light ray orbiting a photon sphere and its analogue, the motion of a uniformly accelerated massive particle and a generalized Doppler effect. The results illustrate how the anisotropic dynamics of the interior of black holes, distinct in the cases both with and without an additional internal horizon, affect non-quantum behaviour.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉A number of recent observations have suggested that the Einstein’s theory of general relativity may not be the ultimate theory of gravity. The 〈em〉f〈/em〉(〈em〉R〈/em〉) gravity model with 〈em〉R〈/em〉 being the scalar curvature turns out to be one of the best bet to surpass the general relativity which explains a number of phenomena where Einstein’s theory of gravity fails. In the 〈em〉f〈/em〉(〈em〉R〈/em〉) gravity, behaviour of the spacetime is modified as compared to that of given by the Einstein’s theory of general relativity. This theory has already been explored for understanding various compact objects such as neutron stars, white dwarfs etc. and also describing evolution of the universe. Although researchers have already found the vacuum spacetime solutions for the 〈em〉f〈/em〉(〈em〉R〈/em〉) gravity, yet there is a caveat that the metric does have some diverging terms and hence these solutions are not asymptotically flat. We show that it is possible to have asymptotically flat spherically symmetric vacuum solution for the 〈em〉f〈/em〉(〈em〉R〈/em〉) gravity, which is different from the Schwarzschild solution. We use this solution for explaining various bound orbits around the black hole and eventually, as an immediate application, in the spherical accretion flow around it.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉In this paper, we implement principal component analysis (PCA) to study the single particle distributions generated from thousands of 〈span〉 〈span〉\(\mathtt {VISH2+1}\)〈/span〉 〈/span〉 hydrodynamic simulations with an aim to explore if a machine could directly discover flow from the huge amount of data without explicit instructions from human-beings. We found that the obtained PCA eigenvectors are similar to but not identical with the traditional Fourier bases. Correspondingly, the PCA defined flow harmonics 〈span〉 〈span〉\(v_n^\prime \)〈/span〉 〈/span〉 are also similar to the traditional 〈span〉 〈span〉\(v_n\)〈/span〉 〈/span〉 for 〈span〉 〈span〉\(n=2\)〈/span〉 〈/span〉 and 3, but largely deviated from the Fourier ones for 〈span〉 〈span〉\(n\ge 4\)〈/span〉 〈/span〉. A further study on the symmetric cumulants and the Pearson coefficients indicates that mode-coupling effects are reduced for these flow harmonics defined by PCA.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉The CRESST (Cryogenic Rare Event Search with Superconducting Thermometers) dark matter search experiment aims for the detection of dark matter particles via elastic scattering off nuclei in 〈span〉 〈span〉\(\mathrm {CaWO_4}\)〈/span〉 〈/span〉 crystals. To understand the CRESST electromagnetic background due to the bulk contamination in the employed materials, a model based on Monte Carlo simulations was developed using the Geant4 simulation toolkit. The results of the simulation are applied to the TUM40 detector module of CRESST-II phase 2. We are able to explain up to 〈span〉 〈span〉\((68 \pm 16)\,\mathrm {\%}\)〈/span〉 〈/span〉 of the electromagnetic background in the energy range between 1 and 〈span〉 〈span〉\(40\,\mathrm {keV}\)〈/span〉 〈/span〉.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉Spinor fields are written in polar form so as to compute their tensorial connection, an object that contains the same information of the connection but which is also proven to be a real tensor. From this, one can still compute the Riemann curvature, encoding the information about gravity. But even in absence of gravity, when the Riemann curvature vanishes, it may still be possible that the tensorial connection remains different from zero, and thih can have effects on matter. This is shown with examples in the two known integrable cases: the hydrogen atom and the harmonic oscillator. The fact that a spinor can feel effects due to sourceless actions is already known in electrodynamics as the Aharonov–Bohm phenomenon. A parallel between the electrodynamics case and the situation encountered here will be drawn. Some ideas about relativistic effects and their role for general treatments of quantum field theories are also underlined.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉In this paper, we calculate the equation of state of two-flavor finite isospin chiral perturbation theory at next-to-leading order in the pion-condensed phase at zero temperature. We show that the transition from the vacuum phase to a Bose-condensed phase is of second order. While the tree-level result has been known for some time, surprisingly quantum effects have not yet been incorporated into the equation of state.  We find that the corrections to the quantities we compute, namely the isospin density, pressure, and equation of state, increase with increasing isospin chemical potential. We compare our results to recent lattice simulations of 2 + 1 flavor QCD with physical quark masses. The agreement with the lattice results is generally good and improves somewhat as we go from leading order to next-to-leading order in 〈span〉 〈span〉\(\chi \)〈/span〉 〈/span〉PT.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉This article is devoted to the study of new exact analytical solutions in the background of Reissner–Nordström space-time by using gravitational decoupling via minimal geometric deformation approach. To do so, we impose the most general equation of state, relating the components of the 〈span〉 〈span〉\(\theta \)〈/span〉 〈/span〉-sector in order to obtain the new material contributions and the decoupler function 〈em〉f〈/em〉(〈em〉r〈/em〉). Besides, we obtain the bounds on the free parameters of the extended solution to avoid new singularities. Furthermore, we show the finitude of all thermodynamic parameters of the solution such as the effective density 〈span〉 〈span〉\({\tilde{\rho }}\)〈/span〉 〈/span〉, radial 〈span〉 〈span〉\({\tilde{p}}_{r}\)〈/span〉 〈/span〉 and tangential 〈span〉 〈span〉\({\tilde{p}}_{t}\)〈/span〉 〈/span〉 pressure for different values of parameter 〈span〉 〈span〉\(\alpha \)〈/span〉 〈/span〉 and the total electric charge 〈em〉Q〈/em〉. Finally, the behavior of some scalar invariants, namely the Ricci 〈em〉R〈/em〉 and Kretshmann 〈span〉 〈span〉\(R_{\mu \nu \omega \epsilon }R^{\mu \nu \omega \epsilon }\)〈/span〉 〈/span〉 scalars are analyzed. It is also remarkable that, after an appropriate limit, the deformed Schwarzschild black hole solution always can be recovered.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉We discuss an inherent Pauli–Villars regularization in Bopp–Podolsky’s generalized electrodynamics. Introducing gauge-fixing terms for Bopp–Podolsky’s generalized electrodynamic action, we realize a unique feature for the corresponding photon propagator with a built-in Pauli–Villars regularization independent of the gauge choice made in Maxwell’s usual electromagnetism. According to our realization, the length dimensional parameter 〈em〉a〈/em〉 associated with Bopp–Podolsky’s higher order derivatives corresponds to the inverse of the Pauli–Villars regularization mass scale 〈span〉 〈span〉\(\Lambda \)〈/span〉 〈/span〉, i.e. 〈span〉 〈span〉\(a = 1/\Lambda \)〈/span〉 〈/span〉. Solving explicitly the classical static Bopp–Podolsky’s equations of motion for a specific charge distribution, we explore the physical meaning of the parameter 〈em〉a〈/em〉 in terms of the size of the charge distribution. As an offspring of the generalized photon propagator analysis, we also discuss our findings regarding on the issue of the two-term vs. three-term photon propagator in light-front dynamics.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉Prepotential formulation of gauge theories on honeycomb lattice yields local loop states, which are exact and orthonormal being free from any spurious loop degrees of freedom. We illustrate that, the dynamics of orthonormal loop states are exactly same in both the square and honeycomb lattices. We further extend this construction to arbitrary dimensions. Utilizing this result, we make a mean field ansatz for loop configurations for SU(2) lattice gauge theory in 〈span〉 〈span〉\(2+1\)〈/span〉 〈/span〉 dimension contributing to the low energy sector of the spectrum. Using variational analysis, we show that, this type of mean loop configurations has two distinct phases in the strong and weak coupling regime and shows a first order transition at 〈span〉 〈span〉\(g=1\)〈/span〉 〈/span〉. We also propose a reduced Hamiltonian to describe the dynamics of the theory within the mean field ansatz. We further work with the mean loop configuration obtained towards the weak coupling limit and analytically calculate the spectrum of the reduced Hamiltonian. The spectrum matches with that of the existing literature in this regime, establishing our ansatz to be a valid alternate one which is far more easier to handle for computation.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉The annual modulation measured by the  DAMA/LIBRA experiment can be explained by the interaction of dark matter WIMPs in NaI(Tl) scintillator detectors. Other experiments, with different targets or techniques, exclude the region of parameters singled out by  DAMA/LIBRA,  but the comparison of their results relies on several hypotheses regarding the dark matter model. ANAIS-112 is a dark matter search with 112.5 kg of NaI(Tl) scintillators at the Canfranc Underground Laboratory (LSC) to test the  DAMA/LIBRA  result in a model independent way. We analyze its prospects in terms of the 〈em〉a priori〈/em〉 critical and detection limits of the experiment. A simple figure of merit has been obtained to compare the different experiments looking for the annual modulation observed by  DAMA/LIBRA.  We conclude that after 5 years of measurement, ANAIS-112 can detect the annual modulation in the 〈span〉 〈span〉\(3\sigma \)〈/span〉 〈/span〉 region compatible with the DAMA/LIBRA result.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉Generation of cosmic microwave background (CMB) elliptic polarization due to the Cotton–Mouton (CM) effect in a cosmic magnetic field is studied. We concentrate on the generation of CMB circular polarization and on the rotation angle of the CMB polarization plane from the decoupling time until at present. For the first time, a rather detailed analysis of the CM effect for an arbitrary direction of the cosmic magnetic field with respect to photon direction of propagation is done. Considering the CMB linearly polarized at the decoupling time, it is shown that the CM effect is one of the most substantial effects in generating circular polarization especially in the low part of the CMB spectrum. It is shown that in the frequency range 〈span〉 〈span〉\(10^8\)〈/span〉 〈/span〉 Hz 〈span〉 〈span〉\(\le \nu _0\le 10^9\)〈/span〉 〈/span〉 Hz, the degree of circular polarization of the CMB at present for perpendicular propagation with respect to the cosmic magnetic field is in the range 〈span〉 〈span〉\( 10^{-13}\lesssim P_C(t_0)\lesssim 7.65\times 10^{-7}\)〈/span〉 〈/span〉 or Stokes circular polarization parameter 〈span〉 〈span〉\(2.7 \times 10^{-13}\)〈/span〉 〈/span〉 K 〈span〉 〈span〉\(\lesssim |V(t_0)|\lesssim 2 \times 10^{-6}\)〈/span〉 〈/span〉 K for values of the cosmic magnetic field amplitude at present in the range 〈span〉 〈span〉\(10^{-9}\)〈/span〉 〈/span〉 G 〈span〉 〈span〉\(\lesssim B\lesssim 8\times 10^{-8}\)〈/span〉 〈/span〉 G. On the other hand, for not perpendicular propagation with respect to the cosmic magnetic field we find 〈span〉 〈span〉\(10^{-15}\lesssim P_C(t_0)\lesssim 6\times 10^{-12}\)〈/span〉 〈/span〉 or 〈span〉 〈span〉\(2.72 \times 10^{-15}\)〈/span〉 〈/span〉 K 〈span〉 〈span〉\(\lesssim |V(t_0)| \lesssim 10^{-11}\)〈/span〉 〈/span〉 K, for the same values of the cosmic magnetic field amplitude and same frequency range. Estimates on the rotation angle of the CMB polarization plane 〈span〉 〈span〉\(\delta \psi _0\)〈/span〉 〈/span〉 due to the CM effect and constraints on the cosmic magnetic field amplitude from current constraints on 〈span〉 〈span〉\(\delta \psi _0\)〈/span〉 〈/span〉 due to a combination of the CM and Faraday effects are found.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉First results on 〈span〉 〈span〉\(\hbox {K}/\pi \)〈/span〉 〈/span〉, 〈span〉 〈span〉\(\hbox {p}/\pi \)〈/span〉 〈/span〉 and K/p fluctuations are obtained with the ALICE detector at the CERN LHC as a function of centrality in 〈span〉 〈span〉\(\text{ Pb--Pb }\)〈/span〉 〈/span〉 collisions at 〈span〉 〈span〉\(\sqrt{s_\mathrm{{NN}}} =2.76\hbox { TeV}\)〈/span〉 〈/span〉. The observable 〈span〉 〈span〉\(\nu _{\mathrm{dyn}}\)〈/span〉 〈/span〉, which is defined in terms of the moments of particle multiplicity distributions, is used to quantify the magnitude of dynamical fluctuations of relative particle yields and also provides insight into the correlation between particle pairs. This study is based on a novel experimental technique, called the Identity Method, which allows one to measure the moments of multiplicity distributions in case of incomplete particle identification. The results for 〈span〉 〈span〉\(\hbox {p}/\pi \)〈/span〉 〈/span〉 show a change of sign in 〈span〉 〈span〉\(\nu _{\mathrm{dyn}}\)〈/span〉 〈/span〉 from positive to negative towards more peripheral collisions. For central collisions, the results follow the smooth trend of the data at lower energies and 〈span〉 〈span〉\(\nu _{\mathrm{dyn}}\)〈/span〉 〈/span〉 exhibits a change in sign for 〈span〉 〈span〉\(\hbox {p}/\pi \)〈/span〉 〈/span〉 and K/p.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉Although the fundamental equations of ordinary thermodynamic systems are known to correspond to first-degree homogeneous functions, in the case of non-ordinary systems like black holes the corresponding fundamental equations are not homogeneous. We present several arguments, indicating that black holes should be described by means of quasi-homogeneous functions of degree different from one. In particular, we show that imposing the first-degree condition leads to contradictory results in thermodynamics and geometrothermodynamics of black holes. As a consequence, we show that in generalized gravity theories the coupling constants like the cosmological constant, the Born–Infeld parameter or the Gauss–Bonnet constant must be considered as thermodynamic variables.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉We determine the model-independent component of the couplings of axions to electroweak gauge bosons, induced by the minimal coupling to QCD inherent to solving the strong CP problem. The case of the invisible QCD axion is developed first, and the impact on 〈em〉W〈/em〉 and 〈em〉Z〈/em〉 axion couplings is discussed. The analysis is extended next to the generic framework of heavy true axions and low axion scales, corresponding to scenarios with enlarged confining sector. The mass dependence of the coupling of heavy axions to photons, 〈em〉W〈/em〉 and 〈em〉Z〈/em〉 bosons is determined. Furthermore, we perform a 〈em〉two-coupling-at-a-time〈/em〉 phenomenological study where the gluonic coupling together with individual gauge boson couplings are considered. In this way, the regions excluded by experimental data for the axion-〈em〉WW〈/em〉, axion-〈em〉ZZ〈/em〉 and axion-〈span〉 〈span〉\(Z\gamma \)〈/span〉 〈/span〉 couplings are determined and analyzed together with the usual photonic ones. The phenomenological results apply as well to ALPs which have anomalous couplings to both QCD and the electroweak bosons.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉Considering de Rham–Gabadadze–Tolley theory of massive gravity coupled with (ghost free) higher curvature terms arisen from the Lovelock Lagrangian, we obtain charged-AdS black hole solutions in diverse dimensions. We compute thermodynamic quantities in the extended phase space by considering the variations of the negative cosmological constant, Lovelock coefficients (〈span〉 〈span〉\(\alpha _{i}\)〈/span〉 〈/span〉) and massive couplings (〈span〉 〈span〉\(c_{i}\)〈/span〉 〈/span〉). We also prove that such variations are necessary in order to satisfy the extended first law of thermodynamics as well as associated Smarr formula. In addition, by performing a comprehensive thermal stability analysis for the topological black hole solutions, we show that in which regions thermally stable phases exist. Calculations show the results are radically different from those in the Einstein gravity. We find that the phase structure and critical behavior of topological AdS black holes are drastically restricted by the geometry of the event horizon. We also show that the phase structure of AdS black holes with non-compact (hyperbolic) horizon could give birth to three critical points corresponds to a reverse van der Waals behavior for phase transition which is accompanied with two distinct van der Waals phase transitions. For black holes with the spherical horizon, the van der Waals, reentrant and analogue of solid/liquid/gas phase transitions are observed.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉We present an implementation of 〈span〉 〈span〉\(WZjj\)〈/span〉 〈/span〉 production via vector-boson fusion in the 〈span〉POWHEG BOX〈/span〉, a public tool for the matching of next-to-leading order QCD calculations with multi-purpose parton-shower generators. We provide phenomenological results for electroweak 〈span〉 〈span〉\(WZjj\)〈/span〉 〈/span〉 production with fully leptonic decays at the LHC in realistic setups and discuss theoretical uncertainties associated with the simulation. We find that beyond the leading-order approximation the dependence on the unphysical factorization and renormalization scales is mild. The two tagging jets are furthermore very stable against parton-shower effects. However, considerable sensitivities to the shower Monte-Carlo program used are observed for central-jet veto observables.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉We study the spontaneous baryogenesis scenario in the early universe for three different frameworks of varying constants theories. We replace the constants by dynamical scalar fields playing the role of thermions. We first obtain the results for baryogenesis driven by the varying gravitational constant, 〈em〉G〈/em〉, as in the previous literature, then challenge the problem for varying fine structure constant 〈span〉 〈span〉\(\alpha \)〈/span〉 〈/span〉 models as well as for varying speed of light 〈em〉c〈/em〉 models. We show that in each of these frameworks the current observational value of the baryon to entropy ratio, 〈span〉 〈span〉\(\eta _B \sim 8.6 \cdot 10^{-11}\)〈/span〉 〈/span〉, can be obtained for large set of parameters of dynamical constants models as well as the decoupling temperature, and the characteristic cut-off length scale.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉The field equations of 〈span〉 〈span〉\(f(R,{\mathcal {G}})\)〈/span〉 〈/span〉 gravity are rewritten in the form of obvious wave equations with the stress–energy pseudotensor of the matter fields and the gravitational field as its source under the de Donder condition. The linearized field equations of 〈span〉 〈span〉\(f(R,{\mathcal {G}})\)〈/span〉 〈/span〉 gravity are the same as those of linearized 〈em〉f〈/em〉(〈em〉R〈/em〉) gravity, and thus, their multipole expansions under the de Donder condition are also the same. It is also shown that the Gauss–Bonnet curvature scalar 〈span〉 〈span〉\({\mathcal {G}}\)〈/span〉 〈/span〉 does not contribute to the effective stress–energy tensor of gravitational waves in linearized 〈span〉 〈span〉\(f(R,{\mathcal {G}})\)〈/span〉 〈/span〉 gravity, though 〈span〉 〈span〉\({\mathcal {G}}\)〈/span〉 〈/span〉 plays an important role in the nonlinear effects in general. Further, by applying the 1 / 〈em〉r〈/em〉 expansion in the distance to the source to the linearized 〈span〉 〈span〉\(f(R,{\mathcal {G}})\)〈/span〉 〈/span〉 gravity, the energy, momentum, and angular momentum carried by gravitational waves in linearized 〈span〉 〈span〉\(f(R,{\mathcal {G}})\)〈/span〉 〈/span〉 gravity are provided, which shows that 〈span〉 〈span〉\({\mathcal {G}}\)〈/span〉 〈/span〉, unlike the nonlinear term 〈span〉 〈span〉\(R^2\)〈/span〉 〈/span〉 in the gravitational Lagrangian, does not contribute to them either.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉Fermions and vector particles tunnelling from non-rotating weakly isolated horizons is investigated in this paper. By applying the WKB approximation to the Dirac equation and Proca equation, we obtain the emission spectrum and Hawking temperature of fermions and vector particles tunnelling from weakly isolated horizons. We consider the back reaction of emitted particles to the space-time, and get the corrected Hawking radiation spectrum. At last we discuss the information recovery of weakly isolated horizons.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉In the present article, we have presented completely new exact, finite and regular class I solutions of Einstein’s field equations i.e. the solutions satisfy the 〈em〉Karmarkar〈/em〉 condition. For this purpose needfully we have introduced a completely new suitable 〈span〉 〈span〉\(g_{rr}\)〈/span〉 〈/span〉 metric potential to generate the model. We have investigated the various physical aspects for our model such as energy density, pressure, anisotropy, energy conditions, equilibrium, stability, mass, surface and gravitational red-shifts, compactness parameter and their graphical representations. All these physical aspects have ensured that our proposed solutions are well-behaved and hence represent physically acceptable models for anisotropic fluid spheres. The models have satisfied causality and energy conditions. The presented models are also stable by satisfying Bondi condition and Abreu et al. condition, in equilibrium position and static by satisfying TOV equation, Harrison–Zeldovich–Novikov condition, respectively. For the parameters chosen in the paper are matching in modeling Vela X-1, Cen X-3, EXO 1785-248 and LMC X-4. The 〈em〉M〈/em〉–〈em〉R〈/em〉 graph generated from the solutions is matching the ranges of masses and radii for the considered compact stars. This work also estimated the approximate moment of inertia for the mentioned compact stars.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉We review the well-known Peebles–Vilenkin (PV) quintessential inflation model and discuss its possible improvements in agreement with the recent observations. The improved PV model depends only on two parameters: the inflaton mass 〈em〉m〈/em〉, and another smaller mass 〈em〉M〈/em〉; where the latter has to be chosen in order to undertake that, at present time, the dark energy density of the universe is approximately about 70% of the total energy budget of the universe. The value of the inflaton mass 〈em〉m〈/em〉 is calculated using the observational value of the power spectrum of the scalar perturbations, and the value of mass 〈em〉M〈/em〉, which depends on the reheating temperature, is calculated by solving the corresponding dynamical system whose initial conditions are taken at the matter-radiation equality and are obtained from three observational data: the red shift at the matter-radiation equality, the ratio of the matter energy density to the critical one at the present time and the current value of the Hubble parameter.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉A search is presented for resonant production of second-generation sleptons (〈span〉 〈span〉\(\widetilde{\mu } _{\mathrm {L}}\)〈/span〉 〈/span〉, 〈span〉 〈span〉\(\widetilde{\nu }_{\mu }\)〈/span〉 〈/span〉) via the 〈em〉R〈/em〉-parity-violating coupling 〈span〉 〈span〉\({\lambda ^{\prime }_{211}}\)〈/span〉 〈/span〉 to quarks, in events with two same-sign muons and at least two jets in the final state. The smuon (muon sneutrino) is expected to decay into a muon and a neutralino (chargino), which will then decay into a second muon and at least two jets. The analysis is based on the 2016 data set of proton-proton collisions at 〈span〉 〈span〉\(\sqrt{s}=13\,\text {TeV} \)〈/span〉 〈/span〉 recorded with the CMS detector at the LHC, corresponding to an integrated luminosity of 35.9〈span〉 〈span〉\(\,\text {fb}^{-1}\)〈/span〉 〈/span〉. No significant deviation is observed with respect to standard model expectations. Upper limits on cross sections, ranging from 0.24 to 730〈span〉 〈span〉\(\,\text {fb}\)〈/span〉 〈/span〉, are derived in the context of two simplified models representing the dominant signal contributions leading to a same-sign muon pair. The cross section limits are translated into coupling limits for a modified constrained minimal supersymmetric model with 〈span〉 〈span〉\({\lambda ^{\prime }_{211}}\)〈/span〉 〈/span〉 as the only nonzero 〈em〉R〈/em〉-parity violating coupling. The results significantly extend restrictions of the parameter space compared with previous searches for similar models.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉By applying copositivity criterion to the scalar potential of the economical 〈span〉 〈span〉\(3-3-1\)〈/span〉 〈/span〉 model, we derive necessary and sufficient bounded-from-below conditions at tree level. Although these are a large number of intricate inequalities for the dimensionless parameters of the scalar potential, we present general enlightening relations in this work. Additionally, we use constraints coming from the minimization of the scalar potential by means of the orbit space method, the positivity of the squared masses of the extra scalars, the Higgs boson mass, the 〈span〉 〈span〉\(Z'\)〈/span〉 〈/span〉 gauge boson mass and its mixing angle with the SM 〈em〉Z〈/em〉 boson in order to further restrict the parameter space of this model.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉The Eisenhart lift is a variant of geometrization of classical mechanics with 〈em〉d〈/em〉 degrees of freedom in which the equations of motion are embedded into the geodesic equations of a Brinkmann-type metric defined on 〈span〉 〈span〉\((d+2)\)〈/span〉 〈/span〉-dimensional spacetime of Lorentzian signature. In this work, the Eisenhart lift of 2-dimensional mechanics on curved background is studied. The corresponding 4-dimensional metric is governed by two scalar functions which are just the conformal factor and the potential of the original dynamical system. We derive a conformal symmetry and a corresponding quadratic integral, associated with the Eisenhart lift. The energy–momentum tensor is constructed which, along with the metric, provides a solution to the Einstein equations. Uplifts of 2-dimensional superintegrable models are discussed with a particular emphasis on the issue of hidden symmetries. It is shown that for the 2-dimensional Darboux–Koenigs metrics, only type I can result in Eisenhart lifts which satisfy the weak energy condition. However, some physically viable metrics with hidden symmetries are presented.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉We present the reach of the proposed INO-ICAL in measuring the atmospheric-neutrino-oscillation parameters 〈span〉 〈span〉\(\theta _{23}\)〈/span〉 〈/span〉 and 〈span〉 〈span〉\(\varDelta m^2_{32}\)〈/span〉 〈/span〉 using full event-by-event reconstruction for the first time. We also study the fluctuations arising from the low event statistics and their effect on the precision measurements and mass-hierarchy analysis for a 5-year exposure of the 50 kton ICAL detector. We find a mean resolution of 〈span〉 〈span〉\(\varDelta \chi ^2 \approx 2.9\)〈/span〉 〈/span〉, which rules out the wrong mass hierarchy of the neutrinos with a significance of approximately 〈span〉 〈span〉\(1.7\sigma \)〈/span〉 〈/span〉. These results on mass-hierarchy are similar to those presented in earlier studies that approximated the performance of the ICAL detector.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉A high statistics data sample of the decays of 〈span〉 〈span〉\(K^+\)〈/span〉 〈/span〉 mesons to three charged particles was accumulated by the OKA experiment in 2012 and 2013. This allowed to select a clean sample of about 450 events with 〈span〉 〈span〉\(K^{+}\rightarrow \pi ^{+}\pi ^{-}\pi ^{+}\gamma \)〈/span〉 〈/span〉 decays with the energy of the photon in the kaon rest frame greater than 30 MeV. The measured branching fraction of the 〈span〉 〈span〉\(K^{+}\rightarrow \pi ^{+}\pi ^{-}\pi ^{+}\gamma \)〈/span〉 〈/span〉, with 〈span〉 〈span〉\(E_{\gamma }^{*} 〉 30\ \hbox {MeV}\)〈/span〉 〈/span〉 is equal to 〈span〉 〈span〉\((0.71 \pm 0.05) \times 10^{-5}\)〈/span〉 〈/span〉. The measured differential branching fraction over photon energy is compared with the prediction of the chiral perturbation theory to 〈span〉 〈span〉\({\mathcal {O}}(p^{4})\)〈/span〉 〈/span〉. A search for an up-down asymmetry of the photon with respect to the hadronic system decay plane is also performed.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉Super-Kamiokande is a gigantic and versatile detector able to detect neutrinos with energies between a few MeV and a few hundred GeV. Super-K started data taking on 1st of April in 1996 after 5 years construction period and obtained compelling evidence of atmospheric neutrino oscillations in 1998, shortly after the beginning of the experiment. In 2001 SNO in Canada together with the Super-K data established that solar neutrinos are also oscillating. Following those historical discoveries, numerous intriguing results have been obtained by Super-K, like the discovery of oscillatory behavior, tau appearance in the atmospheric neutrinos, the matter effect of the solar neutrinos through the earth. The Super-K detector has also been used as a far detector of the long baseline neutrino oscillation experiments, K2K and T2K. In this article, we report mostly on the studies of the neutrino oscillations by Super-K in a historical context. The prospects for the future of Super-K are also described.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉Lattice computations of the high-temperature topological susceptibility of QCD receive lattice-spacing corrections and suffer from systematics arising from the type and depth of gradient flow. We study the lattice spacing corrections to 〈span〉 〈span〉\(\chi _\mathrm {top}\)〈/span〉 〈/span〉 semi-analytically by exploring the behavior of discretized Harrington–Shepard calorons under the action of different forms of gradient flow. From our study we conclude that 〈span〉 〈span〉\(N_\tau = 6\)〈/span〉 〈/span〉 is definitely too small of a time extent to study the theory at temperatures of order 〈span〉 〈span〉\(4~T_\mathrm {c}\)〈/span〉 〈/span〉 and we explore how the amount of gradient flow influences the continuum extrapolation.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉In the context of gravity’s rainbow, we study the deformed Starobinsky model in which the deformations take the form 〈span〉 〈span〉\(f(R)\sim R^{2(1-\alpha )}\)〈/span〉 〈/span〉, with 〈em〉R〈/em〉 and 〈span〉 〈span〉\(\alpha \)〈/span〉 〈/span〉 being the Ricci scalar and a positive parameter, respectively. We show that the spectral index of curvature perturbation and the tensor-to-scalar ratio can be written in terms of 〈span〉 〈span〉\(N,\,\lambda \)〈/span〉 〈/span〉 and 〈span〉 〈span〉\(\alpha \)〈/span〉 〈/span〉, with 〈em〉N〈/em〉 being the number of 〈em〉e〈/em〉-foldings, 〈span〉 〈span〉\(\lambda \)〈/span〉 〈/span〉 a rainbow parameter. We compare the predictions of our models with Planck data. With the sizeable number of 〈em〉e〈/em〉-foldings and proper choices of parameters, we discover that the predictions of the model are in excellent agreement with the Planck analysis. Interestingly, we obtain the upper limit and the lower limit of a rainbow parameter 〈span〉 〈span〉\(\lambda \)〈/span〉 〈/span〉 and a positive constant 〈span〉 〈span〉\(\alpha \)〈/span〉 〈/span〉, respectively.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉There are some examples in the literature, in which despite the fact that the underlying theory or model does not impose a lower bound on the size of black holes, the final temperature under Hawking evaporation is nevertheless finite and nonzero. We show that under some loose conditions, the black hole is necessarily an effective remnant, in the sense that its evaporation time is infinite. That is, the final state that there is nonzero finite temperature despite having no black hole remaining cannot be realized. We discuss the limitations, subtleties, and the implications of this result, which is reminiscent of the third law of black hole thermodynamics, but with the roles of temperature and size interchanged. We therefore refer to our result as the “complementary third law” for black hole thermodynamics.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉The two-Higgs Doublet Model (2HDM) is the most minimal extension of the Standard Model (SM) containing extra Higgs doublet fields. Given the multiplicity of Higgs states in a 2HDM, its Higgs potential is significantly more involved than the SM one. Importantly, it contains a multitude of Higgs triple self-couplings, unlike the SM, which only has one. These interactions are key to understanding the phenomenology of the 2HDM, as they uniquely determine the form of the potential. Several studies analysing the prospects of measuring these couplings at the Large Hadron Collider (LHC) have found them to be quite low generally. However, such studies have largely concentrated on Higgs pair-production induced by gluon-gluon scattering, either via direct annihilation or followed by their splitting into 〈em〉b〈/em〉-(anti)quark pairs, which in turn annihilate leaving behind spectator 〈em〉b〈/em〉-(anti)quarks. Both of these channels are therefore governed by QCD dynamics. We compare here the yields of such channels to those initiated by (primarily) valence quarks, which involve Electro-Weak (EW) interactions only, for neutral multi-Higgs final states. We find that EW production can be dominant over QCD production for certain final state combinations. We also illustrate that charged final states, which can only be produced via EW modes, could serve as important probes of some 〈span〉 〈span〉\(H^\pm \)〈/span〉 〈/span〉 triple couplings, that are inaccessible in QCD-induced processes, during Run 2 and 3 of the LHC. Our analysis covers regions of the parameter space of the Type-I 2HDM that have escaped the most up-to-date experimental constraints coming from EW precision data, LHC measurements of the 125 GeV Higgs boson properties, searches for additional Higgs states, and flavour physics.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉We present a global likelihood function in the space of dimension-six Wilson coefficients in the Standard Model Effective Field Theory. The likelihood includes contributions from flavour-changing neutral current 〈em〉B〈/em〉 decays, lepton flavour universality tests in charged- and neutral-current 〈em〉B〈/em〉 and 〈em〉K〈/em〉 decays, meson-antimeson mixing observables in the 〈em〉K〈/em〉, 〈em〉B〈/em〉, and 〈em〉D〈/em〉 systems, direct CP violation in 〈span〉 〈span〉\(K\rightarrow \pi \pi \)〈/span〉 〈/span〉, charged lepton flavour violating 〈em〉B〈/em〉, tau, and muon decays, electroweak precision tests on the 〈em〉Z〈/em〉 and 〈em〉W〈/em〉 poles, the anomalous magnetic moments of the electron, muon, and tau, and several other precision observables, 265 in total. The Wilson coefficients can be specified at any scale, with the one-loop running above and below the electroweak scale automatically taken care of. The implementation of the likelihood function is based on the open source tools 〈span〉flavio〈/span〉 and 〈span〉wilson〈/span〉 as well as the open Wilson coefficient exchange format (WCxf) and can be installed as a Python package. It can serve as a basis either for model-independent fits or for testing dynamical models, in particular models built to address the anomalies in 〈em〉B〈/em〉 physics. We discuss a number of example applications, reproducing results from the EFT and model building literature.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉Hessian PDF reweighting, or “profiling”, has become a widely used way to study the impact of a new data set on parton distribution functions (PDFs) with Hessian error sets. The available implementations of this method have resorted to a perfectly quadratic approximation of the initial 〈span〉 〈span〉\(\chi ^2\)〈/span〉 〈/span〉 function before inclusion of the new data. We demonstrate how one can take into account the first non-quadratic components of the original fit in the reweighting, provided that the necessary information is available. We then apply this method to the CMS measurement of dijet pseudorapidity spectra in proton–proton (pp) and proton–lead (pPb) collisions at 5.02 TeV. The measured pp dijet spectra disagree with next-to-leading order (NLO) theory calculations using the CT14 NLO PDFs, but upon reweighting the CT14 PDFs, these can be brought to a much better agreement. We show that the needed proton-PDF modifications also have a significant impact on the predictions for the pPb dijet distributions. Taking the ratio of the individual spectra, the proton-PDF uncertainties effectively cancel, giving a clean probe of the PDF nuclear modifications. We show that these data can be used to further constrain the EPPS16 nuclear PDFs and strongly support gluon nuclear shadowing at small 〈em〉x〈/em〉 and antishadowing at around 〈span〉 〈span〉\(x \approx 0.1\)〈/span〉 〈/span〉.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉We generate a general frame work to solve the Einstein system with an equation of state that describe static spherically symmetric anisotropic matter distribution in terms of a generating function. It is examined for a Van der Waals type equation of state with a physically reasonable form of generating function. The model satisfies all the required major physical properties of a realistic star. It is shown to be stable in the low-density regime that may represent a liquid–gas mixed fluid sphere.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉We propose a model of dynamical noncommutative quantum mechanics in which the noncommutative strengths, describing the properties of the commutation relations of the coordinate and momenta, respectively, are arbitrary energy-dependent functions. The Schrödinger equation in the energy-dependent noncommutative algebra is derived for a two-dimensional system for an arbitrary potential. The resulting equation reduces in the small energy limit to the standard quantum mechanical one, while for large energies the effects of the noncommutativity become important. We investigate in detail three cases, in which the noncommutative strengths are determined by an independent energy scale, related to the vacuum quantum fluctuations, by the particle energy, and by a quantum operator representation, respectively. Specifically, in our study we assume an arbitrary power-law energy dependence of the noncommutative strength parameters, and of their algebra. In this case, in the quantum operator representation, the Schrö dinger equation can be formulated mathematically as a fractional differential equation. For all our three models we analyze the quantum evolution of the free particle, and of the harmonic oscillator, respectively. The general solutions of the noncommutative Schrödinger equation as well as the expressions of the energy levels are explicitly obtained.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉In this work, we have studied the combined effect of charge and anisotropy on gravitational interaction of compact sources by making use of generalized polytropic equation of state (GPEoS). We have utilized four different values of polytropic index to ascertain the solution of Einstein–Maxwell field equations and develop a new class of spherically symmetric charged polytropic models. Further, we regain the masses of realistic strange stars 4U 1820-30, PSR J1614-2230, PSR J1903+327, Vela 4U and Vela X-1 that shows viability of the present study. Stability of presented models is analyzed by determining speed of sound that indicates the viability of newly generated models.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉In this work we study an alternative scheme for an Emergent Universe scenario in the context of a Jordan-Brans-Dicke theory, where the universe is initially in a truly static state supported by a scalar field located in a false vacuum. The model presents a classically stable past eternal static state which is broken when, by quantum tunneling, the scalar field decays into a state of true vacuum and the universe begins to evolve following the extended open inflationary scheme.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉The transverse mass of semi-invisibly decaying particles, calculated from the transverse momenta of their decay products, has been used in a broad range of searches and measurements at hadron colliders, such as the LHC. This variable is invariant by construction under Lorentz boosts purely in the longitudinal (beam) direction, thereby minimising sensitivity to fluctuations in the fractions of the proton momentum carried by the colliding partons. In this paper we examine, by contrast, the properties of the transverse mass under boosts with a component also in the transverse plane perpendicular to the beam direction. We show that this variable is invariant under such boosts in cases where the boost is purely transverse and (a) the momenta of the decay products are confined to the transverse plane in the rest frame of the parent particle and/or (b) the transverse momenta of the decay products are perpendicular to the boost direction. We discuss the transformation properties of the transverse mass in the case of combined transverse and longitudinal boosts and identify the criteria under which the transverse mass in the laboratory frame can equal the rest mass of the parent particle, irrespective of its value in the rest frame of the parent.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉An attempt is made to apply the pure spinor formalism to the non-relativistic IIA D2-brane. The fermionic constraints corresponding to the rescaled fermionic coordinates are given. Two commuting spinor fields are introduced, each one corresponding to a fermionic constraint. A BRST charge is constructed via the ansatz proposed by Berkovits in (JHEP 04:018, 〈a href="http://arxiv.org/abs/hep-th/0001035"〉arXiv:hep-th/0001035〈/a〉, 〈span〉2000〈/span〉, JHEP 09:046, 〈a href="http://arxiv.org/abs/hep-th/0006003"〉arXiv:hep-th/0006003〈/a〉, 〈span〉2000〈/span〉, JHEP 09:016, 〈a href="http://arxiv.org/abs/hep-th/0105050"〉arXiv:hep-th/0105050〈/a〉, 〈span〉2001〈/span〉, ICTP Lect. Notes Ser. 13:57, 〈a href="http://arxiv.org/abs/hep-th/0209059"〉arXiv:hep-th/0209059〈/a〉, 〈span〉2003〈/span〉). The nilpotency of the BRST charge leads to a set of constraints for the two spinor fields including pure spinor constraints. A novel non-trivial solution is given for one of the spinor fields which can be written as a sum of two pure spinors.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉The properties of electrically charged strange quark stars are investigated. We assume a non-linear equation-of-state, and we obtain numerical solutions to the structure equations. The key features of the solutions obtained here are (i) they can support a 2 solar masses star, (ii) both the mass and the electric charge of the stars increase with the 〈span〉 〈span〉\(\alpha \)〈/span〉 〈/span〉 parameter characterizing the electric density, (iii) the electric object is heavier and larger than its neutral counterpart.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉In this paper, we propose a viable approach to realise two texture-zeros in the scotogenic model with flavor dependent 〈span〉 〈span〉\(U(1)_{B-2L_\alpha -L_\beta }\)〈/span〉 〈/span〉 gauge symmetry. These models are extended by two right-handed singlets 〈span〉 〈span〉\(N_{Ri}\)〈/span〉 〈/span〉 and two inert scalar doublets 〈span〉 〈span〉\(\eta _{i}\)〈/span〉 〈/span〉, which are odd under the dark 〈span〉 〈span〉\(Z_2\)〈/span〉 〈/span〉 symmetry. Among all the six constructed textures, texture 〈span〉 〈span〉\(A_1\)〈/span〉 〈/span〉 and 〈span〉 〈span〉\(A_2\)〈/span〉 〈/span〉 are the only two allowed by current experimental limits. Then choosing texture 〈span〉 〈span〉\(A_1\)〈/span〉 〈/span〉 derived from 〈span〉 〈span〉\(U(1)_{B-2L_e-L_\tau }\)〈/span〉 〈/span〉, we perform a detail analysis on the corresponding phenomenology such as predictions of neutrino mixing parameters, lepton flavor violation, dark matter and collider signatures. One distinct nature of such model is that the structure of Yukawa coupling 〈span〉 〈span〉\({\bar{L}}{\tilde{\eta }}N_R\)〈/span〉 〈/span〉 is fixed by neutrino oscillation data, and can be further tested by measuring the branching ratios of charged scalars 〈span〉 〈span〉\(\eta _{1,2}^\pm \)〈/span〉 〈/span〉.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉We present a new family of asymptotically locally 〈span〉 〈span〉\(\hbox {AdS}_5\)〈/span〉 〈/span〉 squashed supersymmetric black hole solutions of Fayet–Iliopoulos gauged 〈span〉 〈span〉\({{{\mathcal {N}}}}=2\)〈/span〉 〈/span〉, 〈span〉 〈span〉\(D=5\)〈/span〉 〈/span〉 supergravity with two vector multiplets that have a natural uplift to type IIB supergravity. Our new family of black holes is characterized by three parameters, of which two control the horizon geometry while the latter regulates the squashing at the boundary. We evaluate the main physical properties of the family of solutions using holographic renormalization and find that the entropy is independent on the squashing and it is reproduced by using the angular momentum and the Page charges. In previously known solutions Page and holographic charges are equal, due to the vanishing of the Chern–Simons term that here, instead, is relevant. This result suggests that for asymptotically locally 〈span〉 〈span〉\(\hbox {AdS}_5\)〈/span〉 〈/span〉 solutions we should refer to the Page charges to describe the thermodynamics of the system.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉A rather general form of spherical fluid collapse is formulated. The fluid is anisotropic, has shear, bulk and shear viscosities and is charged. It radiates energy through a heat flow or null radiation. The exterior solution is the charged Vaidya shining star solution. The general junction conditions are given. The main one represents a Riccati equation for the horizon function. We present a simple neutral solution, where the equation becomes a linear one. The whole mass of the star is radiated away without a remnant and the result is flat spacetime.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉Precise predictions for an 〈span〉 〈span〉\(e^+e^-\rightarrow t\bar{t}\)〈/span〉 〈/span〉 cross-section are presented in the energy region from 400 to 800 GeV. Cross-sections are estimated including the beam-polarization effects with full 〈span〉 〈span〉\(\mathcal {O}(\alpha )\)〈/span〉 〈/span〉, and also with the effects of the initial-state photon emission. A radiator technique is used for the initial-state photon emission up to two-loop orders. In this investigation, a weak correction is defined as the full electroweak corrections without the initial-state photonic corrections. As a result, it is determined that the total cross-section of a top quark pair-production receives the weak corrections of 〈span〉 〈span〉\(+\,4\%\)〈/span〉 〈/span〉 over the trivial initial state corrections at a center of mass energy of 500 GeV. Among the initial state contributions, a contribution from two-loop diagrams gives less than 〈span〉 〈span〉\(0.11\%\)〈/span〉 〈/span〉 correction over the one-loop ones at the center of mass energies of from 400 to 800 GeV. In addition, the effect of a running coupling constant is also discussed.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉Many models containing particles which are candidates for dark matter, assume the standard model particles and the dark matter candidates are mediated by a spin-0 particle. At the LHC, one can use these models for dark matter searches. One of the possible approaches for the search of these models is by considering the decay of the spin-0 particle to a pair of 〈span〉 〈span〉\(t{\bar{t}}\)〈/span〉 〈/span〉, thus modifying the pattern of the top quark pair invariant mass spectrum. This search suggests a good sensitivity in a parameter space different than the more traditional searches. We examine this sensitivity and put limits on two benchmark models containing candidates for dark matter, using previous ATLAS results. It was found that when the mediator mass (〈span〉 〈span〉\(m_{Y_0}\)〈/span〉 〈/span〉) and the dark matter candidate mass (〈span〉 〈span〉\(m_{\chi }\)〈/span〉 〈/span〉) have values of 〈span〉 〈span〉\(m_{Y_0} \sim 2 \cdot m_{\chi }\)〈/span〉 〈/span〉, mediator masses in the range of [400, 600] GeV are excluded. We compare our results to direct detection experiments and show that we gain sensitivity for new regions which are not covered by other searches.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉The IceCube Collaboration has observed a high-energy astrophysical neutrino flux and recently found evidence for neutrino emission from the blazar TXS 0506〈span〉 〈span〉\(+\)〈/span〉 〈/span〉056. These results open a new window into the high-energy universe. However, the source or sources of most of the observed flux of astrophysical neutrinos remains uncertain. Here, a search for steady point-like neutrino sources is performed using an unbinned likelihood analysis. The method searches for a spatial accumulation of muon-neutrino events using the very high-statistics sample of about 497,000 neutrinos recorded by IceCube between 2009 and 2017. The median angular resolution is 〈span〉 〈span〉\(\sim 1^\circ \)〈/span〉 〈/span〉 at 1 TeV and improves to 〈span〉 〈span〉\(\sim 0.3^\circ \)〈/span〉 〈/span〉 for neutrinos with an energy of 1 PeV. Compared to previous analyses, this search is optimized for point-like neutrino emission with the same flux-characteristics as the observed astrophysical muon-neutrino flux and introduces an improved event-reconstruction and parametrization of the background. The result is an improvement in sensitivity to the muon-neutrino flux compared to the previous analysis of 〈span〉 〈span〉\(\sim 35\%\)〈/span〉 〈/span〉 assuming an 〈span〉 〈span〉\(E^{-2}\)〈/span〉 〈/span〉 spectrum. The sensitivity on the muon-neutrino flux is at a level of 〈span〉 〈span〉\(E^2 \mathrm {d} N /\mathrm {d} E = 3\cdot 10^{-13}\,\mathrm {TeV}\,\mathrm {cm}^{-2}\,\mathrm {s}^{-1}\)〈/span〉 〈/span〉. No new evidence for neutrino sources is found in a full sky scan and in an a priori candidate source list that is motivated by gamma-ray observations. Furthermore, no significant excesses above background are found from populations of sub-threshold sources. The implications of the non-observation for potential source classes are discussed.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉We apply the method of QCD sum rules to study the structure 〈em〉X〈/em〉 newly observed by the BESIII Collaboration in the 〈span〉 〈span〉\(\phi \eta ^\prime \)〈/span〉 〈/span〉 mass spectrum in 2.0–2.1 GeV region in the 〈span〉 〈span〉\(J/\psi \rightarrow \phi \eta \eta ^\prime \)〈/span〉 〈/span〉 decay. We construct all the 〈span〉 〈span〉\(s s {\bar{s}} {\bar{s}}\)〈/span〉 〈/span〉 tetraquark currents with 〈span〉 〈span〉\(J^{PC} = 1^{+-}\)〈/span〉 〈/span〉, and use them to perform QCD sum rule analyses. One current leads to reliable QCD sum rule results and the mass is extracted to be 〈span〉 〈span〉\(2.00^{+0.10}_{-0.09}\)〈/span〉 〈/span〉 GeV, suggesting that the structure 〈em〉X〈/em〉 can be interpreted as an 〈span〉 〈span〉\(s s {\bar{s}} {\bar{s}}\)〈/span〉 〈/span〉 tetraquark state with 〈span〉 〈span〉\(J^{PC} = 1^{+-}\)〈/span〉 〈/span〉. The 〈em〉Y〈/em〉(2175) can be interpreted as its 〈span〉 〈span〉\(s s {\bar{s}} {\bar{s}}\)〈/span〉 〈/span〉 partner having 〈span〉 〈span〉\(J^{PC} = 1^{--}\)〈/span〉 〈/span〉, and we propose to search for the other two partners, the 〈span〉 〈span〉\(s s {\bar{s}} {\bar{s}}\)〈/span〉 〈/span〉 tetraquark states with 〈span〉 〈span〉\(J^{PC} = 1^{++}\)〈/span〉 〈/span〉 and 〈span〉 〈span〉\(1^{-+}\)〈/span〉 〈/span〉, in the 〈span〉 〈span〉\(\eta ^\prime f_0(980)\)〈/span〉 〈/span〉, 〈span〉 〈span〉\(\eta ^\prime K {\bar{K}}\)〈/span〉 〈/span〉, and 〈span〉 〈span〉\(\eta ^\prime K {\bar{K}}^*\)〈/span〉 〈/span〉 mass spectra.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉In this work, the conversion of linear polarization of a laser beam to circular one through its forward scattering by a TeV order charged lepton beam in the presence of Lorentz violation correction is explored. We calculate the ratio of circular polarization to linear one (Faraday conversion phase 〈span〉 〈span〉\(\Delta \phi _{\mathrm{FC}}\)〈/span〉 〈/span〉) of the laser beam interacting with either electron or the muon beam in the framework of the quantum Boltzmann equation. Regarding the experimentally available sensitivity to the Faraday conversion 〈span〉 〈span〉\(\Delta \phi _{\mathrm{FC}}\simeq 10^{-3}-10^{-2}\)〈/span〉 〈/span〉, we show that the scattering of a linearly polarized laser beam with energy 〈span〉 〈span〉\(k_0\sim 0.1\)〈/span〉 〈/span〉 eV and an electron/muon beam with flux 〈span〉 〈span〉\({\bar{\epsilon }}_{e,\mu }\sim 10^{10}/10^{12}\)〈/span〉 〈/span〉 TeV cm〈span〉 〈span〉\(^{-2}\)〈/span〉 〈/span〉 s〈span〉 〈span〉\(^{-1}\)〈/span〉 〈/span〉 places an upper bound on the combination of lepton sector Lorentz violation coefficients 〈span〉 〈span〉\(c_{\mu \nu }\)〈/span〉 〈/span〉 components 〈span〉 〈span〉\((c_{TT}+1.4~c_{(TZ)}+0.25(c_{XX}+c_{YY}+2~c_{ZZ})\)〈/span〉 〈/span〉. The obtained bound on the combination for the electron beam is at the 〈span〉 〈span〉\(4.35\times 10^{-15}\)〈/span〉 〈/span〉 level and for the muon beam at the 〈span〉 〈span〉\(3.9\times 10^{-13}\)〈/span〉 〈/span〉 level. It should be mentioned that the laser and charged lepton beams considered here to reach the experimentally measurable 〈span〉 〈span〉\(\Delta \phi _{\mathrm{FC}}\)〈/span〉 〈/span〉 are currently available or will be accessible in the near future. This study provides a valuable supplementary to other theoretical and experimental frameworks for measuring and constraining Lorentz violation coefficients.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉ANAIS is a direct detection dark matter experiment aiming at the study of the annual modulation expected in the interaction rate. It uses same target and technique as the DAMA/LIBRA experiment, which reported a highly significant positive modulation compatible with that expected for dark matter particles distributed in the galactic halo. However, other very sensitive experiments do not find any hint of particles with the required properties, although comparison is model dependent. In 2017, ANAIS-112 experiment was installed at the Canfranc Underground Laboratory (LSC), in Spain, and after the commissioning run for calibration and general assessment, ANAIS-112 started data taking in dark matter mode on August 3rd, 2017. It consists of nine NaI(Tl) modules, amounting 112.5 kg of mass in total. Here we report on the experimental apparatus and detector performance after the first year of data taking. Total live time available amounts to 341.72 days, being the corresponding exposure 105.32 kg  〈span〉 〈span〉\(\times \)〈/span〉 〈/span〉  year. ANAIS-112 has achieved an analysis energy threshold of 1 keVee and an average background in the region of interest, from 1 to 6 keVee, of 3.6 counts/keVee/kg/day after correcting by the event selection efficiencies. In these conditions, ANAIS-112 will be able to test the DAMA/LIBRA result at three sigma level in five years of data taking.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉We present for the first time a model-independent anatomy of the ratio 〈span〉 〈span〉\(\varepsilon '/\varepsilon \)〈/span〉 〈/span〉 in the context of the 〈span〉 〈span〉\(\Delta S = 1\)〈/span〉 〈/span〉 effective theory with operators invariant under QCD and QED and in the context of the standard model effective field theory (SMEFT) with the operators invariant under the full SM gauge group. Our goal is to identify the new physics scenarios that are probed by this ratio and which could help to explain a possible deviation from the SM that is hinted by the data. To this end we derive a master formula for 〈span〉 〈span〉\(\varepsilon '/\varepsilon \)〈/span〉 〈/span〉, which can be applied to any theory beyond the standard model (BSM) in which the Wilson coefficients of all contributing operators have been calculated at the electroweak scale. The relevant hadronic matrix elements of BSM operators are from the Dual QCD approach and the SM ones from lattice QCD. Within SMEFT, the constraints from 〈span〉 〈span〉\(K^0\)〈/span〉 〈/span〉 and 〈span〉 〈span〉\(D^0\)〈/span〉 〈/span〉 mixing as well as electric dipole moments limit significantly potential new physics contributions to 〈span〉 〈span〉\(\varepsilon '/\varepsilon \)〈/span〉 〈/span〉. Correlations of 〈span〉 〈span〉\(\varepsilon '/\varepsilon \)〈/span〉 〈/span〉 with 〈span〉 〈span〉\(K\rightarrow \pi \nu {\bar{\nu }}\)〈/span〉 〈/span〉 decays are briefly discussed. Building on our EFT analysis and the model-independent constraints, we discuss implications of a possible deviation from the SM in 〈span〉 〈span〉\(\varepsilon '/\varepsilon \)〈/span〉 〈/span〉 for model building, highlighting the role of the new scalar and tensor matrix elements in models with scalar mediators.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉Neutrino masses could originate in seesaw models testable at colliders, with light mediators and an approximate lepton number symmetry. The minimal model of this type contains two quasi-degenerate Majorana fermions forming a pseudo-Dirac pair. An important question is to what extent future colliders will have sensitivity to the splitting between the Majorana components, since this quantity signals the breaking of lepton number and is connected to the light neutrino masses. We consider the production of these neutral heavy leptons at the ILC, where their displaced decays provide a golden signal: a forward–backward charge asymmetry, which depends crucially on the mass splitting between the two Majorana components. We show that this observable can constrain the mass splitting to values much lower than current bounds from neutrinoless double beta decay and 〈em〉natural〈/em〉 loop corrections.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉In this work we implement the Minimal Geometric Deformation decoupling method to obtain general static interior solutions for a BTZ vacuum from the most general isotropic solution in 〈span〉 〈span〉\(2+1\)〈/span〉 〈/span〉 dimensions including the cosmological constant 〈span〉 〈span〉\(\varLambda \)〈/span〉 〈/span〉. We obtain that the general solution can be generated only by the energy density of the original isotropic sector, so that this quantity plays the role of a generating function. Although as a particular example we study the static star with constant density, the method here developed can be easily applied to more complex situations described by other energy density profiles.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉We present an investigation of the theoretical uncertainties in parton distribution functions (PDFs) due to missing higher-order corrections in the perturbative predictions used in the fit, and their relationship to the uncertainties in subsequent predictions made using the PDFs. We consider in particular the standard approach of factorization and renormalization scale variation, and derive general results for the consistent application of these at the PDF fit stage. To do this, we use the fact that a PDF fit may be recast in a physical basis, where the PDFs themselves are bypassed entirely, and one instead relates measured observables to predicted ones. In the case of factorization scale variation we find that in various situations there is a high degree of effective correlation between the variation in the fit and in predicted observables. In particular, including such a variation in both cases can lead to an exaggerated theoretical uncertainty. More generally, a careful treatment of this correlation appears mandatory, at least within the standard scale variation paradigm. For the renormalization scale, the situation is less straightforward, but again we highlight the potential for correlations between related processes in the fit and predictions to enter at the same level as between processes in the fit or prediction alone.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉Using the background field method, we, in the large 〈span〉 〈span〉\(N_f\)〈/span〉 〈/span〉 approximation, calculate the beta function of scalar quantum electrodynamics at the first nontrivial order in 〈span〉 〈span〉\(1/N_f\)〈/span〉 〈/span〉 by two different ways. In the first way, we get the result by summing all the graphs contributing directly. In the second way, we begin with the Borel transform of the related two point Green’s function. The main results are that the beta function is fully determined by a simple function and can be expressed as an analytic expression with a finite radius of convergence, and the scheme-dependent renormalized Borel transform of the two point Green’s function suffers from renormalons.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉We present a detailed discussion of the triplet anti-triplet symmetry in 3-3-1 models. The full set of conditions to realize this symmetry is provided, which includes in particular the requirement that the two vacuum expectation values of the two scalar triplets responsible for making the 〈em〉W〈/em〉 and 〈em〉Z〈/em〉 bosons massive must be interchanged. We apply this new understanding to the calculation of processes that have a 〈span〉 〈span〉\(Z-Z'\)〈/span〉 〈/span〉 mixing.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉We advance a construction for the covariant holographic entanglement negativity for time dependent mixed states of disjoint intervals in 〈span〉 〈span〉\((1+1)\)〈/span〉 〈/span〉 dimensional conformal field theories (〈span〉 〈span〉\(CFT_{1+1}\)〈/span〉 〈/span〉) dual to bulk non static 〈span〉 〈span〉\(AdS_3\)〈/span〉 〈/span〉 geometries. Application of our proposal to such mixed states in a 〈span〉 〈span〉\(CFT_{1+1}\)〈/span〉 〈/span〉 dual to bulk non extremal and extremal rotating BTZ black holes exactly reproduces the replica technique results in the large central charge limit. We also investigate the time dependent holographic entanglement negativity for such mixed states in a 〈span〉 〈span〉\(CFT_{1+1}\)〈/span〉 〈/span〉 dual to a bulk Vaidya-〈span〉 〈span〉\(AdS_3\)〈/span〉 〈/span〉 geometry in the context of their thermalization involving bulk black hole formation.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉In this work, we pave the way to calculate the productions of 〈span〉 〈span〉\(\omega \)〈/span〉 〈/span〉 and 〈span〉 〈span〉\(K^0_{\mathrm{S}}\)〈/span〉 〈/span〉 mesons with large 〈span〉 〈span〉\(p_T\)〈/span〉 〈/span〉 in p+p and A+A collisions both at RHIC and LHC. The fragmentation functions (FFs) of the 〈span〉 〈span〉\(\omega \)〈/span〉 〈/span〉 meson in vacuum at next-to-leading order (NLO) are obtained by evolving the NLO DGLAP evolution equations with rescaled 〈span〉 〈span〉\(\omega \)〈/span〉 〈/span〉 FFs at initial scale 〈span〉 〈span〉\(Q_0^2=1.5\)〈/span〉 〈/span〉 〈span〉 〈span〉\(\hbox {GeV}^2\)〈/span〉 〈/span〉 from a broken SU(3) model, and the FFs of 〈span〉 〈span〉\(K^0_{\mathrm{S}}\)〈/span〉 〈/span〉 in vacuum are taken from AKK08 parametrization directly. Within the framework of the NLO pQCD improved parton model, we arrive at good descriptions of the experimental data on 〈span〉 〈span〉\(\omega \)〈/span〉 〈/span〉 and 〈span〉 〈span〉\(K^0_{\mathrm{S}}\)〈/span〉 〈/span〉 in p+p both at RHIC and LHC. With the higher-twist approach, to take into account jet quenching effect by medium-modified FFs, nuclear modification factors for 〈span〉 〈span〉\(\omega \)〈/span〉 〈/span〉 meson and 〈span〉 〈span〉\(K^0_{\mathrm{S}}\)〈/span〉 〈/span〉 meson both at RHIC and LHC are presented with different sets of jet transport coefficients 〈span〉 〈span〉\({\hat{q}}_0\)〈/span〉 〈/span〉. Then we make a global extraction of 〈span〉 〈span〉\({\hat{q}}_0\)〈/span〉 〈/span〉 both at RHIC and LHC by confronting our model calculations with all available data on six identified mesons: 〈span〉 〈span〉\(\pi ^0\)〈/span〉 〈/span〉, 〈span〉 〈span〉\(\eta \)〈/span〉 〈/span〉, 〈span〉 〈span〉\(\rho ^0\)〈/span〉 〈/span〉, 〈span〉 〈span〉\(\phi \)〈/span〉 〈/span〉, 〈span〉 〈span〉\(\omega \)〈/span〉 〈/span〉, and 〈span〉 〈span〉\(K^0_{\mathrm{S}}\)〈/span〉 〈/span〉. The minimum value of total 〈span〉 〈span〉\(\chi ^2/d.o.f\)〈/span〉 〈/span〉 for productions of these mesons gives the best value of 〈span〉 〈span〉\({\hat{q}}_0=0.5\mathrm ~GeV^2/fm\)〈/span〉 〈/span〉 for Au+Au collisions with 〈span〉 〈span〉\(\sqrt{s_{\mathrm{NN}}}=200\)〈/span〉 〈/span〉 GeV at RHIC, and 〈span〉 〈span〉\({\hat{q}}_0=1.2\mathrm ~GeV^2/fm\)〈/span〉 〈/span〉 for Pb+Pb collisions with 〈span〉 〈span〉\(\sqrt{s_{\mathrm{NN}}}=2.76\)〈/span〉 〈/span〉 TeV at LHC, respectively, with the QGP spacetime evolution given by the event-by-event viscous hydrodynamics model IEBE-VISHNU. With these global extracted values of 〈span〉 〈span〉\({\hat{q}}_0\)〈/span〉 〈/span〉, nuclear modification factors of 〈span〉 〈span〉\(\pi ^0\)〈/span〉 〈/span〉, 〈span〉 〈span〉\(\eta \)〈/span〉 〈/span〉, 〈span〉 〈span〉\(\rho ^0\)〈/span〉 〈/span〉, 〈span〉 〈span〉\(\phi \)〈/span〉 〈/span〉, 〈span〉 〈span〉\(\omega \)〈/span〉 〈/span〉, and 〈span〉 〈span〉\(K^0_{\mathrm{S}}\)〈/span〉 〈/span〉 in A+A collisions are presented, and predictions of yield ratios such as 〈span〉 〈span〉\(\omega /\pi ^0\)〈/span〉 〈/span〉 and 〈span〉 〈span〉\(K^0_{\mathrm{S}}/\pi ^0\)〈/span〉 〈/span〉 at the high-〈span〉 〈span〉\(p_T\)〈/span〉 〈/span〉 regime in heavy-ion collisions both at RHIC and LHC are provided.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉We study an extension of the Standard Model that addresses the hints of lepton flavour universality violation observed in 〈span〉 〈span〉\(B\rightarrow K^{(*)} l^+l^-\)〈/span〉 〈/span〉 decays at LHCb, while providing a viable candidate for dark matter. The model incorporates two new scalar fields and a Majorana fermion that induce one-loop contributions to 〈em〉B〈/em〉 meson decays. We show that agreement with observational data requires the new couplings to be complex and that the Majorana fermion can reproduce the observed dark matter relic density. This combination of cosmological and flavour constraints sets an upper limit on the dark matter and mediator masses. We have studied LHC dijet and dilepton searches, finding that they rule out large regions of parameter space by setting lower bounds on the dark matter and mediator masses. In particular, dilepton bounds are much more constraining in a future high-luminosity phase. Finally, we have computed the scattering cross section of dark matter off nuclei and compared it to the sensitivity of current and future direct detection experiments, showing that parts of the parameter space could be accessible in the future to multi-ton experiments. Future collider and direct DM searches complement each other to probe large areas of the parameter space of this model.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉We suggest a modified form of a unitarized BFKL equation imposing the so-called kinematic constraint on the gluon evolution in multi-Regge kinematics. The underlying nonlinear effects on the gluon evolution are investigated by solving the unitarized BFKL equation analytically. We obtain an equation of the critical boundary between dilute and dense partonic system, following a new differential geometric approach and sketch a phenomenological insight on geometrical scaling. Later we illustrate the phenomenological implication of our solution for unintegrated gluon distribution 〈span〉 〈span〉\(f(x,k_T^2)\)〈/span〉 〈/span〉 towards exploring high precision HERA DIS data by theoretical prediction of proton structure functions (〈span〉 〈span〉\(F_2\)〈/span〉 〈/span〉 and 〈span〉 〈span〉\(F_L\)〈/span〉 〈/span〉) as well as double differential reduced cross section 〈span〉 〈span〉\((\sigma _r)\)〈/span〉 〈/span〉. The validity of our theory in the low 〈span〉 〈span〉\(Q^2\)〈/span〉 〈/span〉 transition region is established by studying virtual photon–proton cross section in light of HERA data.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉In this article, we propose a novel channel for phenomenological studies of the double-parton scattering (DPS) based upon associated production of charm 〈span〉 〈span〉\(c{\bar{c}}\)〈/span〉 〈/span〉 and bottom 〈span〉 〈span〉\(b{\bar{b}}\)〈/span〉 〈/span〉 quark pairs in well-separated rapidity intervals in ultraperipheral high-energy proton–nucleus collisions. This process provides direct access to the double-gluon distribution in the proton at small-〈em〉x〈/em〉 and enables one to test the factorized DPS pocket formula. We have made the corresponding theoretical predictions for the DPS contribution to this process at typical LHC energies and beyond and we compute the energy-independent (but photon momentum fraction dependent) effective cross section.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉A measurement of fiducial and differential cross-sections for 〈span〉 〈span〉\(W^+W^-\)〈/span〉 〈/span〉 production in proton–proton collisions at 〈span〉 〈span〉\(\sqrt{s}=13\)〈/span〉 〈/span〉 TeV with the ATLAS experiment at the Large Hadron Collider using data corresponding to an integrated luminosity of 36.1 〈span〉 〈span〉\(\hbox {fb}^{-1}\)〈/span〉 〈/span〉 is presented. Events with one electron and one muon are selected, corresponding to the decay of the diboson system as 〈span〉 〈span〉\(WW\rightarrow e^{\pm }\nu \mu ^{\mp }\nu \)〈/span〉 〈/span〉. To suppress top-quark background, events containing jets with a transverse momentum exceeding 35 GeV are not included in the measurement phase space. The fiducial cross-section, six differential distributions and the cross-section as a function of the jet-veto transverse momentum threshold are measured and compared with several theoretical predictions. Constraints on anomalous electroweak gauge boson self-interactions are also presented in the framework of a dimension-six effective field theory.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉The quantum gravity correction to the Hawking temperature of the 2+1 dimensional spinning dilaton black hole is studied by using the Hamilton-Jacobi approach in the context of the Generalized Uncertainty Principle (GUP). It is observed that the modified Hawking temperature of the black hole depends on both black hole and the tunnelling particle properties. Moreover, it is observed that the mass and the angular momentum of the scalar particle have the same effect on the Hawking temperature of the black hole, while the mass and total angular momentum (orbital+spin) of Dirac particle have different effect. Furthermore, the mass and total angular momentum (orbital+spin) of vector boson particle have a similar effect that of Dirac particle. Also, thermodynamical stability and phase transition of the black hole are discussed for scalar, Dirac and vector boson in the context of GUP, respectively. And, it is observed that the scalar particle probes the black hole as stable whereas, as for Dirac and vector boson particles, it might undergoes second-type phase transition to become stable while in the absence of the quantum gravity effect all of these particle probes the black hole as stable.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉A Weyl structure is usually defined by an equivalence class of pairs 〈span〉 〈span〉\((\mathbf{g}, {\varvec{\omega }})\)〈/span〉 〈/span〉 related by Weyl transformations, which preserve the relation 〈span〉 〈span〉\(\nabla \mathbf{g}={\varvec{\omega }}\otimes \mathbf{g}\)〈/span〉 〈/span〉, where 〈span〉 〈span〉\(\mathbf{g}\)〈/span〉 〈/span〉 and 〈span〉 〈span〉\({\varvec{\omega }}\)〈/span〉 〈/span〉 denote the metric tensor and a 1-form field. An equivalent way of defining such a structure is as an equivalence class of conformally related metrics with a unique affine connection 〈span〉 〈span〉\(\Gamma _{({\varvec{\omega }})}\)〈/span〉 〈/span〉, which is invariant under Weyl transformations. In a standard Weyl structure, this unique connection is assumed to be torsion-free and have vectorial non-metricity. This second view allows us to present two different generalizations of standard Weyl structures. The first one relies on conformal symmetry while allowing for a general non-metricity tensor, and the other comes from extending the symmetry to arbitrary (disformal) transformations of the metric.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉We report the improved test of frame-dragging, an intriguing phenomenon predicted by Einstein’s General Relativity, obtained using 7 years of Satellite Laser Ranging (SLR) data of the satellite LARES (ASI, 2012) and 26 years of SLR data of LAGEOS (NASA, 1976) and LAGEOS 2 (ASI and NASA, 1992). We used the static part and temporal variations of the Earth gravity field obtained by the space geodesy mission GRACE (NASA and DLR) and in particular the static Earth’s gravity field model GGM05S augmented by a model for the 7-day temporal variations of the lowest degree Earth spherical harmonics. We used the orbital estimator GEODYN (NASA). We measured frame-dragging to be equal to 〈span〉 〈span〉\(0.9910 \pm 0.02\)〈/span〉 〈/span〉, where 1 is the theoretical prediction of General Relativity normalized to its frame-dragging value and 〈span〉 〈span〉\(\pm 0.02\)〈/span〉 〈/span〉 is the estimated systematic error due to modelling errors in the orbital perturbations, mainly due to the errors in the Earth’s gravity field determination. Therefore, our measurement confirms the prediction of General Relativity for frame-dragging with a few percent uncertainty.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉We study several physical aspects of the dressed elliptic strings propagating on 〈span〉 〈span〉\(\mathbb {R} \times \mathrm {S}^2\)〈/span〉 〈/span〉 and of their counterparts in the Pohlmeyer reduced theory, i.e. the sine-Gordon equation. The solutions are divided into two wide classes; kinks which propagate on top of elliptic backgrounds and non-localised periodic disturbances of the latter. The former class of solutions obey a specific equation of state that is in principle experimentally verifiable in systems which realize the sine-Gordon equation. Among both of these classes, there appears to be a particular class of interest the closed dressed strings. They in turn form four distinct subclasses of solutions. One of those realizes instabilities of the seed elliptic solutions. The existence of such solutions depends on whether a superluminal kink with a specific velocity can propagate on the corresponding elliptic sine-Gordon solution. Unlike the elliptic strings, the dressed ones exhibit interactions among their spikes. These interactions preserve an appropriately defined turning number, which can be associated to the topological charge of the sine-Gordon counterpart. Finally, the dispersion relations of the dressed strings are studied. A qualitative difference between the two wide classes of dressed strings is discovered.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉We present the first performance results obtained with microwave multiplexed Transition Edge Sensors prototypes specifically designed for the HOLMES experiment, a project aimed at directly measuring the electron neutrino mass through the calorimetric measurement of the 〈span〉 〈span〉\(^{163}\)〈/span〉 〈/span〉Ho electron capture spectrum. The detectors required for such an experiment feature a high energy resolution at the 〈em〉Q〈/em〉–value of the transition, around 〈span〉 〈span〉\(\sim \)〈/span〉 〈/span〉 2.8 keV, and a fast response time combined with the compatibility to be multiplexed in large arrays in order to collect a large statistics while keeping the pile-up contribution as small as possible. In addition, the design has to be suitable for future ion-implantation of 〈span〉 〈span〉\(^{163}\)〈/span〉 〈/span〉Ho. The results obtained in these tests allowed us to identify the optimal detector design among several prototypes. The chosen detector achieved an energy resolution of (4.5 ± 0.3) eV on the chlorine K〈span〉 〈span〉\(_\alpha \)〈/span〉 〈/span〉 line, at 〈span〉 〈span〉\(\sim \)〈/span〉 〈/span〉 2.6 keV, obtained with an exponential rise time of 14 〈span〉 〈span〉\(\upmu \)〈/span〉 〈/span〉s. The achievements described in this paper pose a milestone for the HOLMES detectors, setting a baseline for the subsequent developments, aiming to the actual ion-implantation of the 〈span〉 〈span〉\(^{163}\)〈/span〉 〈/span〉Ho nuclei. In the first section the HOLMES experiment is outlined along with its physics goal, while in the second section the HOLMES detectors are described; the experimental set-up and the calibration source used for the measurements described in this paper are reported in Sects. 〈span〉3〈/span〉 and 〈span〉4〈/span〉, respectively; finally, the details of the data analysis and the results obtained are reported in Sect. 〈span〉6〈/span〉.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉We investigate the binding energy parameters that should be used in modeling electron and neutrino scattering from nucleons bound in a nucleus within the framework of the impulse approximation. We discuss the relation between binding energy, missing energy, removal energy (〈span〉 〈span〉\(\epsilon \)〈/span〉 〈/span〉), spectral functions and shell model energy levels and extract updated removal energy parameters from 〈span〉 〈span〉\(\hbox {ee}^{\prime }\)〈/span〉 〈/span〉p spectral function data. We address the difference in parameters for scattering from bound protons and neutrons. We also use inclusive e-A data to extract an empirical parameter 〈span〉 〈span〉\(U_{FSI}( (\varvec{q}_3+\varvec{k})^2)\)〈/span〉 〈/span〉 to account for the interaction of final state nucleons (FSI) with the optical potential of the nucleus. Similarly we use 〈span〉 〈span〉\(V_{eff}\)〈/span〉 〈/span〉 to account for the Coulomb potential of the nucleus. With three parameters 〈span〉 〈span〉\(\epsilon \)〈/span〉 〈/span〉, 〈span〉 〈span〉\(U_{FSI}( (\varvec{q}_3+\varvec{k})^2)\)〈/span〉 〈/span〉 and 〈span〉 〈span〉\(V_{eff}\)〈/span〉 〈/span〉 we can describe the energy of final state electrons for all available electron QE scattering data. The use of the updated parameters in neutrino Monte Carlo generators reduces the systematic uncertainty in the combined removal energy (with FSI corrections) from ± 20 to ± 5 MeV.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉We discuss how inflation can emerge from a four-fermion interaction induced by torsion. Inflation can arise from coupling torsion to Standard Model fermions, without any need of introducing new scalar particles beyond the Standard Model. Within this picture, the inflaton field can be a composite field of the SM-particles and arises from a Nambu–Jona-Lasinio mechanism in curved space-time, non-minimally coupled with the Ricci scalar. The model we specify predicts small value of the r-parameter, namely 〈span〉 〈span〉\(r\sim 10^{-4} \div 10^{-2}\)〈/span〉 〈/span〉, which nonetheless would be detectable by the next generation of experiments, including BICEP 3 and the AliCPT projects.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉We study the trace anomaly of a Weyl fermion in an abelian gauge background. Although the presence of the chiral anomaly implies a breakdown of gauge invariance, we find that the trace anomaly can be cast in a gauge invariant form. In particular, we find that it does not contain any odd-parity contribution proportional to the Chern–Pontryagin density, which would be allowed by the consistency conditions. We perform our calculations using Pauli–Villars regularization and heat kernel methods. The issue is analogous to the one recently discussed in the literature about the trace anomaly of a Weyl fermion in curved backgrounds.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉Liquid argon-based scintillation detectors are important for dark matter searches and neutrino physics. Argon scintillation light is in the vacuum ultraviolet region, making it hard to be detected by conventional means. Polyethylene naphthalate (PEN), an optically transparent thermoplastic polyester commercially available as large area sheets or rolls, is proposed as an alternative wavelength shifter to the commonly-used tetraphenyl butadiene (TPB). By combining the existing literature data and spectrometer measurements relative to TPB, we conclude that the fluorescence yield and timing of both materials may be very close. The evidence collected suggests that PEN is a suitable replacement for TPB in liquid argon neutrino detectors, and is also a promising candidate for dark matter detectors. Advantages of PEN are discussed in the context of scaling-up existing technologies to the next generation of very large ktonne-scale detectors. Its simplicity has a potential to facilitate such scale-ups, revolutionizing the field.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉The top quark mass is measured using a template method in the 〈span〉 〈span〉\(t\bar{t} \rightarrow \mathrm {lepton+jets}\)〈/span〉 〈/span〉 channel (lepton is 〈em〉e〈/em〉 or 〈span〉 〈span〉\(\mu \)〈/span〉 〈/span〉) using ATLAS data recorded in 2012 at the LHC. The data were taken at a proton–proton centre-of-mass energy of 〈span〉 〈span〉\({\sqrt{s}} =8\)〈/span〉 〈/span〉 〈span〉 〈span〉\(\text {TeV}\)〈/span〉 〈/span〉 and correspond to an integrated luminosity of 〈span〉 〈span〉\(20.2\)〈/span〉 〈/span〉  fb〈span〉 〈span〉\(^{-1}\)〈/span〉 〈/span〉. The 〈span〉 〈span〉\(t\bar{t} \rightarrow \mathrm {lepton+jets}\)〈/span〉 〈/span〉 channel is characterized by the presence of a charged lepton, a neutrino and four jets, two of which originate from bottom quarks (〈em〉b〈/em〉). Exploiting a three-dimensional template technique, the top quark mass is determined together with a global jet energy scale factor and a relative 〈em〉b〈/em〉-to-light-jet energy scale factor. The mass of the top quark is measured to be 〈span〉 〈span〉\(m_{\mathrm {top}} =172.08 \,\pm \,0.39 \,\mathrm {(stat)}\,\pm \,0.82 \,\mathrm {(syst)} \)〈/span〉 〈/span〉 〈span〉 〈span〉\(\text {GeV}\)〈/span〉 〈/span〉. A combination with previous ATLAS 〈span〉 〈span〉\(m_{\mathrm {top}}\)〈/span〉 〈/span〉 measurements gives 〈span〉 〈span〉\(m_{\mathrm {top}} = 172.69 \,\pm \,0.25 \,\mathrm {(stat)}\,\pm \,0.41 \,\mathrm {(syst)} \)〈/span〉 〈/span〉 〈span〉 〈span〉\(\text {GeV}\)〈/span〉 〈/span〉.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉We propose a new scientific application of unsupervised learning techniques to boost our ability to search for new phenomena in data, by detecting discrepancies between two datasets. These could be, for example, a simulated standard-model background, and an observed dataset containing a potential hidden signal of New Physics. We build a statistical test upon a test statistic which measures deviations between two samples, using a Nearest Neighbors approach to estimate the local ratio of the density of points. The test is model-independent and non-parametric, requiring no knowledge of the shape of the underlying distributions, and it does not bin the data, thus retaining full information from the multidimensional feature space. As a proof-of-concept, we apply our method to synthetic Gaussian data, and to a simulated dark matter signal at the Large Hadron Collider. Even in the case where the background can not be simulated accurately enough to claim discovery, the technique is a powerful tool to identify regions of interest for further study.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉In the present work we consider the existence and stability of Einstein static 〈span〉ES〈/span〉 Universe in Brans–Dicke (〈span〉BD〈/span〉) theory with non-vanishing spacetime torsion. In this theory, torsion field can be generated by the 〈span〉BD〈/span〉 scalar field as well as the intrinsic angular momentum (spin) of matter. Assuming the matter content of the Universe to be a Weyssenhoff fluid, which is a generalization of perfect fluid in general relativity (〈span〉GR〈/span〉) in order to include the spin effects, we find that there exists a stable 〈span〉ES〈/span〉 state for a suitable choice of the model parameters. We analyze the stability of the solution by considering linear homogeneous perturbations and discuss the conditions under which the solution can be stable against these type of perturbations. Moreover, using dynamical system techniques and numerical analysis, the stability regions of the 〈span〉ES〈/span〉 Universe are parametrized by the 〈span〉BD〈/span〉 coupling parameter and first and second derivatives of the 〈span〉BD〈/span〉 scalar field potential, and it is explicitly shown that a large class of stable solutions exists within the respective parameter space. This allows for non-singular emergent cosmological scenarios where the Universe oscillates indefinitely about an initial 〈span〉ES〈/span〉 solution and is thus past eternal.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉The scalarization of Reissner–Nordström black holes was recently proposed in the Einstein-Maxwell-scalar theory. Here, we show that the appearance of the scalarized Reissner–Nordström black hole is closely related to the Gregory-Laflamme instability of the Reissner–Nordström black hole without scalar hair.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉In this article, we predict the standard model (SM) values of the asymmetric and angular observables in 〈span〉 〈span〉\(B\rightarrow D^{(*)}\tau \nu _{\tau }\)〈/span〉 〈/span〉 decays, using the results of the new up-to-date analysis in 〈span〉 〈span〉\(B\rightarrow D^{(*)}\ell \nu _{\ell }\)〈/span〉 〈/span〉. We also revisit the SM prediction of the inclusive ratio 〈span〉 〈span〉\({\mathcal {R}}_{X_c}\)〈/span〉 〈/span〉, and we give its values in different schemes of the charm quark mass. This is the first analysis which includes all the known corrections in the SM. In addition, we analyze the 〈span〉 〈span〉\(b\rightarrow c\tau \nu _\tau \)〈/span〉 〈/span〉 decay modes in a model-independent framework of effective field theory beyond the standard model. Considering all the possible combinations of the effective operators in 〈span〉 〈span〉\(b \rightarrow c \tau \nu _{\tau }\)〈/span〉 〈/span〉 decays and using the Akaike information criterion, we find the scenarios which can best explain the available data on these channels. In the selected scenarios, best-fit values and correlations of the new parameters are extracted. Using these results, predictions are made on various observables in the exclusive and inclusive semitaunic 〈span〉 〈span〉\(b \rightarrow c \)〈/span〉 〈/span〉 decays. The graphical correlations between these observables are shown, which are found to be useful in discriminating various new physics scenarios.〈/p〉

Description: 〈h3〉Abstract〈/h3〉 〈p〉Measurements are presented of associated production of a 〈span〉 〈span〉\(\mathrm {W}\)〈/span〉 〈/span〉 boson and a charm quark (〈span〉 〈span〉\(\mathrm {W}+\mathrm {c}\)〈/span〉 〈/span〉) in proton–proton collisions at a center-of-mass energy of 13〈span〉 〈span〉\(\,\text {Te}\text {V}\)〈/span〉 〈/span〉. The data correspond to an integrated luminosity of 35.7〈span〉 〈span〉\(\,\text {fb}^{-1}\)〈/span〉 〈/span〉 collected by the CMS experiment at the CERN LHC. The 〈span〉 〈span〉\(\mathrm {W}\)〈/span〉 〈/span〉 bosons are identified by their decay into a muon and a neutrino. The charm quarks are tagged via the full reconstruction of 〈span〉 〈span〉\({\mathrm {D}^{*}(2010)^{\pm }}\)〈/span〉 〈/span〉 mesons that decay via 〈span〉 〈span〉\({\mathrm {D}^{*}(2010)^{\pm }}\rightarrow \mathrm {D}^0 + {\pi ^{\pm }}\rightarrow \mathrm {K}^{\mp } + {\pi ^{\pm }}+ {\pi ^{\pm }}\)〈/span〉 〈/span〉. A cross section is measured in the fiducial region defined by the muon transverse momentum 〈span〉 〈span〉\(p_{\mathrm {T}} ^{\mu } 〉 26\,\text {Ge}\text {V} \)〈/span〉 〈/span〉, muon pseudorapidity 〈span〉 〈span〉\(|\eta ^{\mu } | 〈 2.4\)〈/span〉 〈/span〉, and charm quark transverse momentum 〈span〉 〈span〉\(p_{\mathrm {T}} ^{\mathrm {c}} 〉 5\,\text {Ge}\text {V} \)〈/span〉 〈/span〉. The inclusive cross section for this kinematic range is 〈span〉 〈span〉\(\sigma (\mathrm {W}+\mathrm {c})=1026\pm 31\,\text {(stat)} \begin{array}{c} +76\\ -72 \end{array}\,\text {(syst)} \text { pb} \)〈/span〉 〈/span〉. The cross section is also measured differentially as a function of the pseudorapidity of the muon from the 〈span〉 〈span〉\(\mathrm {W}\)〈/span〉 〈/span〉 boson decay. These measurements are compared with theoretical predictions and are used to probe the strange quark content of the proton.〈/p〉