ALBERT — All Library Books, journals and Electronic Records Telegrafenberg

1

Digitale Medien

The ten-channel pulsed radar reflectometer at the TEXTOR-94 tokamak : Papers from the thirteenth topical conference on high temperature plasma diagnostics (2001)

van Gorkom, J. C. ; van de Pol, M. J. ; Donné, A. J. H.

[S.l.] : American Institute of Physics (AIP)

Review of Scientific Instruments 72 (2001), S. 336-339

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 1089-7623

Quelle: AIP Digital Archive

Thema: Physik , Elektrotechnik, Elektronik, Nachrichtentechnik

Notizen: A new ten-channel pulsed radar reflectometer has been taken into operation at the Torus Experiment for Technology Oriented Research-94. The system will be used simultaneously as a density profile and as a density fluctuation diagnostic. Ten density layers from 0.4×1019 to 4×1019 m−3 can be probed simultaneously at 2 MHz. The design of the diagnostic has undergone some changes, to improve reliability of the system. Examples of time delay measurements are shown. These examples illustrate the fluctuation capabilities of the diagnostic at high time resolution, as well as the response of the different channels to density profile changes. © 2001 American Institute of Physics.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1063/1.1316747

Permalink

	Standort	Signatur	Erwartet	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext

2

Digitale Medien

A synchrotron radiation diagnostic to observe relativistic runaway electrons in a tokamak plasma : Papers from the thirteenth topical conference on high temperature plasma diagnostics (2001)

Jaspers, R. ; Lopes Cardozo, N. J. ; Donné, A. J. H. ; [weitere]

[S.l.] : American Institute of Physics (AIP)

Review of Scientific Instruments 72 (2001), S. 466-470

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 1089-7623

Quelle: AIP Digital Archive

Thema: Physik , Elektrotechnik, Elektronik, Nachrichtentechnik

Notizen: In present day tokamaks runaway electrons can be confined long enough to gain energies in the order of several tens of megaelectron volts. At these energies synchrotron radiation is emitted in the infrared wavelength range which can easily be detected by thermographic cameras. The spectral features of this synchrotron radiation are reviewed. On TEXTOR-94 a diagnostic exploiting this synchrotron radiation has been developed and is presented here. It is shown how to deduce the runaway parameters like runaway energy, pitch angle, runaway current and beam radius from the measurements. Based on the experience at TEXTOR-94 the feasibility of a similar synchrotron diagnostic on the International Thermonuclear Experimental Reactor is discussed. The maximum emission is expected in the wavelength range from 1–5 μm. A beam of 10 MeV runaway electrons with a current of about 15 kA will already be detectable. © 2001 American Institute of Physics.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1063/1.1318245

Permalink

	Standort	Signatur	Erwartet	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext

3

Digitale Medien

New diagnostics for physics studies on TEXTOR-94 (invited) : Papers from the thirteenth topical conference on high temperature plasma diagnostics (2001)

Donné, A. J. H. ; Jaspers, R. ; Barth, C. J. ; [weitere]

[S.l.] : American Institute of Physics (AIP)

Review of Scientific Instruments 72 (2001), S. 1046-1053

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 1089-7623

Quelle: AIP Digital Archive

Thema: Physik , Elektrotechnik, Elektronik, Nachrichtentechnik

Notizen: Recently the Dutch, Belgian, and North-Rhine Westphalian Fusion Institutes have consolidated their fusion research on the medium-sized tokamak TEXTOR-94 in the so-called Trilateral Euregio Cluster. To aid the new physics program of TEC, a large number of advanced core diagnostics has recently been implemented. In this article we will discuss the reasoning that has led to the choices of the various diagnostics. Furthermore, we will briefly describe the new diagnostics systems. © 2001 American Institute of Physics.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1063/1.1321740

Permalink

	Standort	Signatur	Erwartet	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext

4

Digitale Medien

Fast pulsed radar reflectometry for the Textor Tokamak : Proceedings of the 12th topical conference on high temperature plasma diagnostics (1999)

Hugenholtz, C. A. J. ; Donné, A. J. H. ; Elzendoorn, B. S. Q. ; [weitere]

[S.l.] : American Institute of Physics (AIP)

Review of Scientific Instruments 70 (1999), S. 1034-1037

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 1089-7623

Quelle: AIP Digital Archive

Thema: Physik , Elektrotechnik, Elektronik, Nachrichtentechnik

Notizen: Progress in fusion research shows an increasing demand for diagnostics with high temporal and spatial resolution in order to study small and fast phenomena in fusion plasmas. Therefore, a new ten-channel pulsed radar reflectometer is under development for the TEXTOR Tokamak, to measure electron density profiles in the range of 0.4–4×1019 m−3 at a high repetition rate of 2 MHz. An additional feature of this diagnostic is the possibility to perform correlation measurements at 10 MHz repetition rate to investigate density fluctuations. The reflectometer will scan the plasma with 1-ns-long radar pulses in the 18–57 GHz range. In spite of the long flight time of the pulses of about 100 ns, the above mentioned high repetition rates could be achieved by time multiplexing the generation and reception of the radar pulses. Temporal selection of the received pulses is performed by fast switching of the local oscillators inputs of the heterodyne receiver, to generate time windows in which the reception of the reflected pulses is expected. An embedded VME controller will manage the system and store the data with a speed of 20 Msamples/s, up to a maximum of 64 Mbyte data per plasma shot. In order to facilitate the handling of such a huge amount of data, an advanced data reduction scheme is being developed. Remote operation with a fast data link from FZ Jülich (Germany) to FOM Nieuwegein (The Netherlands) will be possible. © 1999 American Institute of Physics.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1063/1.1149426

Permalink

	Standort	Signatur	Erwartet	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext

5

Digitale Medien

The multichannel triple-laser interferometer/polarimeter system at RTP (abstract) : Proceedings of the eleventh topical conference on high temperature plasma diagnostics (1997)

Rommers, J. H. ; Donné, A. J. H. ; Karelse, F. A.

[S.l.] : American Institute of Physics (AIP)

Review of Scientific Instruments 68 (1997), S. 446-446

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 1089-7623

Quelle: AIP Digital Archive

Thema: Physik , Elektrotechnik, Elektronik, Nachrichtentechnik

Notizen: A 19-channel combined interferometer and polarimeter system has recently become operational at the Rijnhuizen Tokamak Project (a=0.164 m, R=0.72 m, Btor≤2.5 T, Ip≤150 kA, plasma pulse duration ≤500 ms), in order to determine the poloidal magnetic field and plasma density distribution simultaneously. The method is based on the separate propagation of two counter-rotating, circularly polarized probing waves, and enables high temporal resolution measurements of both the interferometric and the polarimetric phase change using only one detector per line of sight. In this article a thorough discussion of the (polarization-related) optical, electronic, and computational aspects of the system will be presented.© 1997 American Institute of Physics.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1063/1.1147602

Permalink

	Standort	Signatur	Erwartet	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext

6

Digitale Medien

First tomographic reconstructions and a study of interference filters for visible-light tomography on RTP : Proceedings of the tenth topical conference on high temperature plasma diagnostics (1995)

Ingesson, L. C. ; Pickalov, V. V. ; Donné, A. J. H. ; [weitere]

[S.l.] : American Institute of Physics (AIP)

Review of Scientific Instruments 66 (1995), S. 622-624

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 1089-7623

Quelle: AIP Digital Archive

Thema: Physik , Elektrotechnik, Elektronik, Nachrichtentechnik

Notizen: An 80-channel visible-light tomography diagnostic is operational on the Rijnhuizen Tokamak Project. This diagnostic uses optical imaging systems from five directions in one poloidal plane to view emission by the plasma. For the application of tomography algorithms, measurements need to be preprocessed to take into account the properties of the imaging system. These properties have been measured and a consistent treatment is demonstrated. An example of a tomographic inversion of a glow-discharge plasma is given. Optical filters can be used to select various wavelength ranges. Because the imaging system gives large angles of incidence on the filter (〈16°), a study has been made to determine the minimum useful bandwidth of interference filters to select spectral lines, which was found to be 5 nm. © 1995 American Institute of Physics.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1063/1.1146541

Permalink

	Standort	Signatur	Erwartet	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext

7

Digitale Medien

Photon recycling system for multiposition tangential Thomson scattering : Proceedings of the tenth topical conference on high temperature plasma diagnostics (1995)

Barth, C. J. ; Chu, C. C. ; Donné, A. J. H.

[S.l.] : American Institute of Physics (AIP)

Review of Scientific Instruments 66 (1995), S. 501-503

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 1089-7623

Quelle: AIP Digital Archive

Thema: Physik , Elektrotechnik, Elektronik, Nachrichtentechnik

Notizen: Multiposition tangential Thomson scattering makes it possible to measure the profiles of the local drift velocity and current density of a tokamak plasma. To achieve a reasonably small observational error (20%) a high photon yield is required. In this paper we propose an optical system to increase the photon yield by about a factor of 7. Photons from a pulsed ruby laser are captured in a ring cavity by means of an electro-optical switch. The trapped laser beam recirculates about 14 times through the sampling volume which is part of the cavity, increasing the laser energy of 25 J to an effective energy of about 140 J. © 1995 American Institute of Physics.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1063/1.1146330

Permalink

	Standort	Signatur	Erwartet	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext

8

Digitale Medien

H−-conversion aided detection of low-energy H0 fluxes from the TORTUR tokamak in a time-of-flight analyzer (1992)

van Toledo, W. ; van Buuren, R. ; Donné, A. J. H. ; [weitere]

[S.l.] : American Institute of Physics (AIP)

Review of Scientific Instruments 63 (1992), S. 2223-2231

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 1089-7623

Quelle: AIP Digital Archive

Thema: Physik , Elektrotechnik, Elektronik, Nachrichtentechnik

Notizen: A time-of-flight spectrometer has been developed to examine the velocity distribution of the hydrogen charge-exchange particles emitted from the TORTUR tokamak. To investigate the scrape-off layer, the spectrometer has been made sensitive to low-energy hydrogen atoms. This has been done by converting the hydrogen atoms into more easily detectable negative hydrogen ions on a cesiated monocrystalline tungsten surface. This detection technique enables examination of the neutral particle flux in a large energy range (5–2000 eV). Typical examples of time-of-flight spectra recorded during TORTUR discharges will be shown.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1063/1.1143143

Permalink

	Standort	Signatur	Erwartet	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext

9

Digitale Medien

New ECE diagnostics for the TEXTOR-94 tokamak : Papers from the thirteenth topical conference on high temperature plasma diagnostics (2001)

Udintsev, V. S. ; van de Pol, M. J. ; Donné, A. J. H.

[S.l.] : American Institute of Physics (AIP)

Review of Scientific Instruments 72 (2001), S. 359-362

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 1089-7623

Quelle: AIP Digital Archive

Thema: Physik , Elektrotechnik, Elektronik, Nachrichtentechnik

Notizen: To aid the scientific research program on the Toroidal Experiment for Technology Oriented Research (TEXTOR)-94 tokamak, the existing electron cyclotron emission (ECE) diagnostics for the electron temperature studies are being extended with new systems that feature a good temporal and radial resolution. Using the possibility of obtaining the data on a fast time scale, ECE systems allow one to study fast phenomena like the dynamics of small-scale structures such as magnetic islands and transport barriers and microscopic temperature fluctuations throughout the plasma. The quantitative information about nonthermal electron populations can be obtained from the comparison of the second and third harmonic emission. A new 16-channel frequency tunable radiometer and a four-channel second harmonic system were recently installed at TEXTOR-94. The detailed description of the new TEXTOR-94 ECE systems and the recent results will be given and discussed in this article. © 2001 American Institute of Physics. [DOI: 10.1063/1.1309001]

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1063/1.1309001

Permalink

	Standort	Signatur	Erwartet	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext

10

Digitale Medien

Poloidal polarimeter system for current density measurements in ITER : Proceedings of the 12th topical conference on high temperature plasma diagnostics (1999)

Donné, A. J. H.

[S.l.] : American Institute of Physics (AIP)

Review of Scientific Instruments 70 (1999), S. 726-729

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 1089-7623

Quelle: AIP Digital Archive

Thema: Physik , Elektrotechnik, Elektronik, Nachrichtentechnik

Notizen: The polarimeter system for ITER features 10 viewing chords covering almost the full poloidal cross section of the plasma in a fan-like arrangement. The 10 laser beams all enter the plasma via 150 mm diam penetrations through the diagnostic plug at the low-field side. Small retroreflectors at the high-field side mirror the laser beams back towards the penetrations at the low-field side. Extensive feasibility calculations have led to the conclusion that the optimum wavelength for the polarimeter is around 100 μm. At this wavelength counterproductive effects like refraction and electron cyclotron absorption are negligibly small. However, the anticipated Faraday rotation angles are still very large, such that several important plasma parameters can be measured within the requirements set by the ITER team. In this article the status of the conceptual design of the polarimeter system for ITER will be presented. © 1999 American Institute of Physics.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1063/1.1149396

Permalink

	Standort	Signatur	Erwartet	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext