Examinando por Autor "Del Santo, M."

Mostrando 1 - 3 de 3

Restringido
Accretion in strong field gravity with eXTP
(Springer Link, 2018-12-07) De Rosa, A.; Uttley, P.; Gou, L.; Liu, Y.; Bambi, C.; Barret, Didier; Belloni, T.; Berti, E.; Bianchi, S.; Caiazzo, I.; Casella, P.; Cui, W. K.; D´Ammando, F.; Dauser, T.; Del Santo, M.; De Marco, B.; Di Salvo, T.; Done, C.; Dovciak, M.; Fabian, A. C.; Falanga, M.; Gambino, A. F.; Gendre, B.; Grinberg, V.; Heger, A.; Homan, J.; Iaria, R.; Jiang, J.; Jin, C. C.; Koerding, E.; Linares, M.; Liu, Z.; Maccarone, Thomas J.; Malzac, J.; Manousakis, A.; Marin, F.; Marinucci, A.; Mehdipour, M.; Méndez, M.; Migliari, S.; Miller, C.; Miniutti, G.; Nardini, E.; O´Brien, P. T.; Osborne, Julian P.; Petrucci, P. O.; Possenti, A.; Riggio, A.; Rodríguez, J.; Sanna, A.; Shao, L. J.; Sobolewska, M.; Sramkova, E.; Stevens, A. L.; Stiele, H.; Stratta, G.; Stuchlik, Z.; Svoboda, J.; Tamburini, F.; Tauris, T. M.; Tombesi, F.; Torok, G.; Urbanec, M.; Vicent, F.; Wu, Q. W.; Yuan, F.; Zand, J. J. M.; Zdziarski, A. A.; Zhou, X.; Feroci, M.; Ferrari, V.; Gualtieri, L.; Heyl, J.; Ingram, A.; Karas, V.; Lu, F. J.; Luo, B.; Matt, G.; Motta, S. E.; Neilsen, J.; Pani, P.; Santangelo, A.; Shu, X. W.; Wang, J. F.; Wang, J. M.; Xue, Y. Q.; Xu, Y. P.; Yuan, W. M.; Yuan, Y. F.; Zhang, S. N.; Zhang, S.; Agudo, I.; Amati, L.; Andersson, N. A.; Baglio, C.; Bakala, P.; Baykal, A.; Bhattacharyya, S.; Bombaci, I.; Bucciantini, N.; Capitanio, F.; Ciolfi, R.; Istituto Nazionale di Astrofisica (INAF); Chinese Academy of Sciences (CAS); National Science Centre, Poland (NCN)
In this paper we describe the potential of the enhanced X-ray Timing and Polarimetry (eXTP) mission for studies related to accretion flows in the strong field gravity regime around both stellar-mass and supermassive black-holes. eXTP has the unique capability of using advanced “spectral-timing-polarimetry” techniques to analyze the rapid variations with three orthogonal diagnostics of the flow and its geometry, yielding unprecedented insight into the inner accreting regions, the effects of strong field gravity on the material within them and the powerful outflows which are driven by the accretion process. X-spinmeasurements
Acceso Abierto
Observations of a radio-bright, X-ray obscured GRS 1915+105
(Oxford Academics: Oxford University Press, 2021-02-24) Motta, Sara E.; Kajava, J. J. E.; Giustini, M.; Williams, D. R. A.; Del Santo, M.; Fender, R.; Green, D. A.; Heywood, I.; Rhodes, L.; Segreto, A.; Sivakoff, G.; Woudt, P. A.; Science and Technology Facilities Council (STFC); Agencia Estatal de Investigación (AEI); Comunidad de Madrid; Istituto Nazionale di Astrofisica (INAF); European Commission (EC); Motta, S. E. [0000-0002-6154-5843]; Kajava, J. J. E. [0000-0002-3010-8333]; Williams, D. R. A. [0000-0001-7361-0246]; Del Santo, M. [0000-0002-1793-1050]; Green, D. A. [0000-0003-3189-9998]; Woudt, P. A. [0000-0002-6896-1655]
The Galactic black hole transient GRS 1915+105 is famous for its markedly variable X-ray and radio behaviour, and for being the archetypal galactic source of relativistic jets. It entered an X-ray outburst in 1992 and has been active ever since. Since 2018 GRS 1915+105 has declined into an extended low-flux X-ray plateau, occasionally interrupted by multiwavelength flares. Here, we report the radio and X-ray properties of GRS 1915+105 collected in this new phase, and compare the recent data to historic observations. We find that while the X-ray emission remained unprecedentedly low for most of the time following the decline in 2018, the radio emission shows a clear mode change half way through the extended X-ray plateau in 2019 June: from low flux (∼3 mJy) and limited variability, to marked flaring with fluxes two orders of magnitude larger. GRS 1915+105 appears to have entered a low-luminosity canonical hard state, and then transitioned to an unusual accretion phase, characterized by heavy X-ray absorption/obscuration. Hence, we argue that a local absorber hides from the observer the accretion processes feeding the variable jet responsible for the radio flaring. The radio–X-ray correlation suggests that the current low X-ray flux state may be a signature of a super-Eddington state akin to the X-ray binaries SS433 or V404 Cyg.
Restringido
Observatory science with eXTP
(Springer Link, 2018-08-30) Zand, J. J. M.; Bozzo, E.; Qu, J.; Li, X. D.; Amati, L.; Chen, Y.; Donnarumma, I.; Doroshenko, V.; Drake, S. A.; Hernanz, M.; Jenke, P. A.; Baykal, A.; Cumming, A.; Miller, M. C.; Gendre, B.; McHardy, I.; Peretz, U.; Schatz, H.; Brown, E. F.; Neubert, T.; Gill, R.; Mikusincova, R.; Prescod Weinstein, C.; Shearer, A.; Campana, R.; Pacciani, L.; Götz, D.; Rodríguez, J.; Stappers, B. W.; Chambers, F.; Paul, B.; Gouiffès, C.; Rózanska, A.; Strohmayer, T. E.; Chenevez, J.; De Martino, D.; Malzac, J.; Suleimanov, V. F.; Ciolfi, R.; Tauris, T. M.; Méndez, M.; Svoboda, J.; D´aì, A.; Atteia, J. L.; Motch, C.; Thielemann, F. K.; D´Ammando, F.; Mahmoodifar, S.; Tombesi, F.; Degenaar, N.; Zingale, M.; Torres, D. F.; D´Elia, V.; Zhang, S.; Torresi, E.; Doyle, G.; Zhang, S. N.; Fan, X.; Zdziarski, A. A.; Malyshev, D.; Zane, S.; Maccarone, Thomas J.; Zampieri, L.; Zhang, X.; Yuan, F.; Stratta, G.; Yu, W.; Younes, G.; Yan, Z.; Xu, Y.; Xiong, S. L.; Sala, G.; Agudo, I.; Ballantyne, D. R.; Bianchi, S.; Brandt, S.; Cackett, E. M.; Grandi, P.; Granot, J.; Güdel, M.; Heger, A.; Heinke, C. O.; Homan, J.; Iaria, R.; Iwasawa, K.; Izzo, L.; Ji, L.; Del Santo, M.; De Pasquale, M.; Dai, Z. G.; Constantin, E.; Chernyakova, M.; Chen, L.; Casella, P.; Burderi, L.; Braga, J.; Belloni, T.; Andersson, N. A.; Osborne, Julian P.; Wilms, J.; Nardini, E.; De Rosa, A.; Behar, E.; Turriziani, S.; Altamirano, D.; Cavecchi, Y.; Di Salvo, T.; Papadakis, L. E.; Blay, P.; Vacchi, A.; Chen, Y. P.; Falanga, M.; Pérez Torres, M. A.; Bucciantini, N.; Vercellone, S.; Jin, C. C.; Ferdman, R. D.; Reig, P.; Campana, S.; Rowlinson, A.; Feroci, M.; Rodríguez Gil, P.; Lu., F.; Zhou, P.; Fraschetti, F.; Sakamoto, T.; Mehdipour, M.; Baglio, C.; Galloway, D. K.; Salvaterra, R.; Bhattacharyya, S.; Gambino, A. F.; Santagelo, A.; Longo, F.; Gandhi, P.; Schanne, S.; Liang, E. W.; Ge, M.; Shao, L.; Kunneriath, D.; Shore, S. N.; Kuiper, L.; Rossi, E. M.; Kreykenbohm, I.; Wu, X.; Komossa, S.; Linares, M.; Keek, L.; Li, G.; Kawai, N.; Kargaltsev, O.; Kalemci, E.; Kaastra, J. S.; José, J.; Jonker, P. G.; Manousakis, A.; Mignani, R. P.; Nättilä, J.; Orlandini, M.; Paolillo, M.; Vink, J. S.; Wang, J. J.; Wang, J. F.; Watts, A. L.; Weng, S.; Weinberg, N. N.; Wheatley, P. J.; Wijnands, R.; Woods, T. E.; Woosley, S. E.; Savolainen, T.; Sanna, A.; Salmi, T.; Romano, P.; Riggio, A.; Perinati, E.; Pellizzoni, A.; Paltani, Stéphane; O´Brien, P. T.; Miniutti, G.; Men, Y.; Bilous, A.; Lutovinov, A. A.; National Natural Science Foundation of China (NSFC); European Research Council (ERC); National Aeronautics and Space Administration (NASA); Agencia Estatal de Investigación (AEI); Royal Society; Strategic Priority Research Program of the Chinese Academy of Sciences; European Research Council (ERC); National Science Centre, Poland (NCN); Unidad de Excelencia Científica María de Maeztu Instituto de Ciencias del Cosmos (ICCUB), MDM-2014-0369
In this White Paper we present the potential of the enhanced X-ray Timing and Polarimetry (eXTP) mission for studies related to Observatory Science targets. These include flaring stars, supernova remnants, accreting white dwarfs, low and high mass X-ray binaries, radio quiet and radio loud active galactic nuclei, tidal disruption events, and gamma-ray bursts. eXTP will be excellently suited to study one common aspect of these objects: their often transient nature. Developed 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.