ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Publication Date: 2016-03-26
    Description: : We introduce a new forward-time simulator, Admix’em, that allows for rapid and realistic simulations of admixed populations with selection. Complex selection can be achieved through user-defined fitness and mating-preference probability functions. Users can specify realistic genomic landscapes and model neutral SNPs in addition to sites under selection. Admix’em is designed to simulate selection in admixed populations but can also be used as a general population simulator. Usage and examples are in the supplement. Availability and Implementation: C ++ and OpenMP, supports 64-bit Linux/Unix-like platforms. https://github.com/melop/admixem . Contact: rcui@age.mpg.de Supplementary information: Supplementary data are available at Bioinformatics online.
    Print ISSN: 1367-4803
    Electronic ISSN: 1460-2059
    Topics: Biology , Computer Science , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Publication Date: 2020-06-19
    Description: Planets open gaps in discs. Gap opening is typically modelled by considering the planetary Lindblad torque which repels disc gas away from the planet’s orbit. But gaps also clear because the planet consumes local material. We present a simple, easy-to-use, analytic framework for calculating how gaps deplete and how the disc’s structure as a whole changes by the combined action of Lindblad repulsion and planetary consumption. The final mass to which a gap-embedded gas giant grows is derived in tandem. The analytics are tested against 1D numerical experiments and calibrated using published multidimensional simulations. In viscous alpha discs, the planet, while clearing a gap, initially accretes practically all of the gas that tries to diffuse past, rapidly achieving super-Jupiter if not brown dwarf status. By contrast, in inviscid discs – that may still accrete on to their central stars by, say, magnetized winds – planets open deep, repulsion-dominated gaps. Then only a small fraction of the disc accretion flow is diverted on to the planet, which grows to a fraction of a Jupiter mass. Transitional disc cavities might be cleared by families of such low-mass objects opening inviscid, repulsion-dominated, overlapping gaps which allow most of the outer disc gas to flow unimpeded on to host stars.
    Print ISSN: 0035-8711
    Electronic ISSN: 1365-2966
    Topics: Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Publication Date: 2020-09-09
    Description: We present the results of the first dedicated survey for 22 GHz H2O maser emission in dwarf galaxies outside of the Local Group, with the aim of discovering disc masers. Studies of disc masers yield accurate and precise measurements of black hole (BH) mass, and such measurements in dwarf galaxies would be key to understanding the low-mass end of BH–galaxy coevolution. We used the Green Bank Telescope to survey 100 nearby (z ≲ 0.055) dwarf galaxies (M* ≲ 109.5 M⊙) with optical emission line ratios indicative of accretion on to a massive black hole. We detected no new masers down to a limit of ∼12 mJy (5σ). We compared the properties of our sample with those of ∼1850 known detections and non-detections in massive galaxies. We find, in agreement with previous studies, that masers are preferentially hosted by Seyferts and highly obscured, [O iii]-bright active galactic nuclei (AGNs). Our sample has fewer Seyferts, is less obscured, and is [O iii]-faint. Though the overall maser detection rate is ∼3 per cent in massive galaxies, the predicted rate for our sample, weighted by its optical properties, is ∼0.6–1.7 per cent, corresponding to a probability of making no detections of ∼20–50 per cent. We also found a slight increase in the detection rate with increased stellar mass in previously surveyed galaxies. However, further observations are required to discern whether there is an intrinsic difference between the maser fraction in active dwarf galaxies and in their massive counterparts for the same AGN properties.
    Print ISSN: 0035-8711
    Electronic ISSN: 1365-2966
    Topics: Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...