Search

Your search keyword '"Török, Gabriel"' showing total 104 results
Start Over Author "Török, Gabriel"
104 results on '"Török, Gabriel"'

101. A remark about possible unity of the neutron star and black hole high frequency QPOs.

Author

Török, Gabriel, Stuchlík, Zdeněk, and Bakala, Pavel

Abstract

In a series of papers it was discussed,on the basis of phenomenological arguments, whether the high frequency quasiperiodic oscillations (kHz QPOs)observed in the neutron-star and black-hole X-ray sources originate in the same physical mechanism. Recently it was suggested that a general trend seen in neutron star kHz QPOs instead excludes such a uniform origin. Using the example of the atoll source 4U 1636-53 we illustrate that this is not neccesarily true. [ABSTRACT FROM AUTHOR]

Published
2007
Full Text
View/download PDF

102. QPOs in Microquasars: the Spin Problem.

Author

Török, Gabriel, Abramowicz, Marek A., Stuchlík, Zdeněk, and Šrámkováovo nám. 13, CZ-74601 Opava, Czech Republic. email: terek@volny.cz, zdenek.stuchlik@fpf.slu.cz, sram_eva@centrum.cz, Eva

Abstract

In Galactic microquasars with double-peak kHz quasi-periodic oscillations (QPOs), the ratio of the two frequencies is 3:2. This supports the suggestion that double-peak kHz QPOs are due to a non-linear resonance between two modes of accretion disk oscillations. For the microquasars with known mass, we briefly compare the black hole spin estimates based on the orbital resonance model with the recently reported spin predictions obtained by fitting the spectral continua. Results of these two approaches are not in good agreement. We stress that if the spectral fit estimates are accurate and can be taken as referential (which is still questionable), the disagreement between the predicted and referential values would represent a rather generic problem for any relativistic QPO model, as no spin influence would appear in the observed 1/M scaling of the QPO frequencies. The epicyclic frequencies relevant in these models are often considered to be equal to those of a test particle motion. However modifications of the frequencies due to disc pressure or other non-geodesic effects may play an important role, and the inaccuracy introduced in the spin estimates by the test particle approximation could be crucial. [ABSTRACT FROM PUBLISHER]

Published
2008
Full Text
View/download PDF

104. Dense matter with eXTP

Author

Xiang-Dong Li, Jean in 't Zand, B. W. Stappers, Sudip Bhattacharyya, Slavko Bogdanov, Holger Stiele, Sharon M. Morsink, Tiziana Di Salvo, Zhaosheng Li, Robert D. Ferdman, Alessandro Riggio, Jin-Lu Qu, Wenfei Yu, Oleg Kargaltsev, R. Iaria, Xia Zhou, Joonas Nättilä, Gabriel Török, David Tsang, Aleksi Kurkela, Laura Tolos, Achim Schwenk, Ingo Tews, Ypeng Xu, Andrea Vacchi, Martin Urbanec, Andrea Santangelo, Xiao Yu Lai, Manuel Linares, Pavel Bakala, Altan Baykal, Anna L. Watts, Alexander Heger, Eva Šrámková, Andrea Sanna, Maurizio Falanga, Ang Li, M. Coleman Miller, Federico Bernardini, Edward F. Brown, Yuri Cavecchi, Jérôme Chenevez, Long Ji, Dieter H. Hartmann, Hendrik Schatz, Ignazio Bombaci, Shuang-Nan Zhang, Silvia Zane, Chanda Prescod-Weinstein, Victor Doroshenko, Kai Hebeler, Guobao Zhang, Tuomo Salmi, Fangjun Lu, Ming-Yu Ge, Melania Del Santo, Deepto Chakrabarty, Mariano Mendez, ShiJie Zheng, Wenda Zhang, S. K. Greif, Alessandro Patruno, Angelo Gambino, Nathalie Degenaar, Simin Mahmoodifar, Juri Poutanen, Marco Feroci, Thomas E. Riley, Shu Zhang, Andrea Possenti, Sebastien Guillot, Tod E. Strohmayer, Jeroen Homan, Can Güngör, Li-Ming Song, Renxin Xu, Universitat Politècnica de Catalunya. Departament de Física, Universitat Politècnica de Catalunya. GAA - Grup d'Astronomia i Astrofísica, High Energy Astrophys. & Astropart. Phys (API, FNWI), Astronomy, Watts, Anna L., Yu, WenFei, Poutanen, Juri, Zhang, Shu, Bhattacharyya, Sudip, Bogdanov, Slavko, Ji, Long, Patruno, Alessandro, Riley, Thomas E., Bakala, Pavel, Baykal, Altan, Bernardini, Federico, Bombaci, Ignazio, Brown, Edward, Cavecchi, Yuri, Chakrabarty, Deepto, Chenevez, Jérôme, Degenaar, Nathalie, Del Santo, Melania, Di Salvo, Tiziana, Doroshenko, Victor, Falanga, Maurizio, Ferdman, Robert D., Feroci, Marco, Gambino, Angelo F., Ge, MingYu, Greif, Svenja K., Guillot, Sebastien, Gungor, Can, Hartmann, Dieter H., Hebeler, Kai, Heger, Alexander, Homan, Jeroen, Iaria, Rosario, Zand, Jean in’t, Kargaltsev, Oleg, Kurkela, Aleksi, Lai, XiaoYu, Li, Ang, Li, XiangDong, Li, ZhaoSheng, Linares, Manuel, Lu, FangJun, Mahmoodifar, Simin, Méndez, Mariano, Coleman Miller, M., Morsink, Sharon, Nättilä, Joona, Possenti, Andrea, Prescod-Weinstein, Chanda, Qu, JinLu, Riggio, Alessandro, Salmi, Tuomo, Sanna, Andrea, Santangelo, Andrea, Schatz, Hendrik, Schwenk, Achim, Song, LiMing, Šrámková, Eva, Stappers, Benjamin, Stiele, Holger, Strohmayer, Tod, Tews, Ingo, Tolos, Laura, Török, Gabriel, Tsang, David, Urbanec, Martin, Vacchi, Andrea, Xu, RenXin, Xu, YuPeng, Zane, Silvia, Zhang, GuoBao, Zhang, ShuangNan, Zhang, WenDa, Zheng, ShiJie, and Zhou, Xia

Subjects
GAMMA-RAY PULSARS, dense matter, Astrophysics::High Energy Astrophysical Phenomena, Polarimetry, General Physics and Astronomy, FOS: Physical sciences, Astrophysics, Neutron, BRIGHTNESS OSCILLATIONS, 7. Clean energy, 01 natural sciences, INNER ACCRETION DISKS, Spectral line, X-ray, equation of state, neutron, X-rays, Physics and Astronomy (all), Equacions d'estat, Pulsar, 0103 physical sciences, MILLISECOND PULSARS, NEUTRON-STAR, RADIUS CONSTRAINTS, 010306 general physics, 010303 astronomy & astrophysics, RELATIVISTIC IRON LINE, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), LIGHT CURVES, Neutrons, Equation of state, QUASI-PERIODIC OSCILLATIONS, X-Rays, Starke Wechselwirkung und exotische Kerne – Abteilung Blaum, Astrophysics::Instrumentation and Methods for Astrophysics, EQUATION-OF-STATE, Accretion (astrophysics), Neutron star, Física::Astronomia i astrofísica [Àrees temàtiques de la UPC], Raigs X, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - High Energy Astrophysical Phenomena, Dense matter
Abstract

In this White Paper we present the potential of the Enhanced X-ray Timing and Polarimetry (eXTP) mission for determining the nature of dense matter; neutron star cores host an extreme density regime which cannot be replicated in a terrestrial laboratory. The tightest statistical constraints on the dense matter equation of state will come from pulse profile modelling of accretion-powered pulsars, burst oscillation sources, and rotation-powered pulsars. Additional constraints will derive from spin measurements, burst spectra, and properties of the accretion flows in the vicinity of the neutron star. Under development by an international Consortium led by the Institute of High Energy Physics of the Chinese Academy of Science, the eXTP mission is expected to be launched in the mid 2020s., Comment: Accepted for publication on Sci. China Phys. Mech. Astron. (2019)

Published
2019

Catalog

Books, media, physical & digital resources
See catalog results