@Article{CastroDABrMaPoWi:2014:CoThCo,
               author = "Castro, Manuel Antonio and D'Amico, Fl{\'a}vio and Braga, 
                         Jo{\~a}o and Maiolino, T. and Pottschmidt, K. and Wilms, J.",
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto 
                         Nacional de Pesquisas Espaciais (INPE)} and {Instituto Nacional de 
                         Pesquisas Espaciais (INPE)} and Physics Earth Sciences Department, 
                         University of FerraraFerrara, Italy; Universit{\'e} de Nice 
                         Sophia-AntipolisNice, France and Cresst, NASA, GSFC, United States 
                         and Remeis Observatory and ECAP, University of 
                         Erlangen-NurembergBamberg, Germany",
                title = "Confirming the thermal comptonization model for black hole X-ray 
                         emission in the low-hard state",
              journal = "Astronomy \& Astrophysics",
                 year = "2014",
               volume = "569",
               number = "A82",
                month = "Sept.",
             keywords = "Black holes, Comptonization, Radiation mechanisms: nonthermal, 
                         Radiation mechanisms: thermal, X rays: stars, X-ray emission.",
             abstract = "Hard X-ray spectra of black hole binaries in the low/hard state 
                         are well modeled by thermal Comptonization of soft seed photons by 
                         a corona-type region with kT ~ 50 keV and optical depth around 1. 
                         Previous spectral studies of 1E 1740.7-2942, including both the 
                         soft and the hard X-ray bands, were always limited by gaps in the 
                         spectra or by a combination of observations with imaging and 
                         non-imaging instruments. In this study, we have used three rare 
                         nearly-simultaneous observations of 1E 1740.7-1942 by both 
                         XMM-Newton and INTEGRAL satellites to combine spectra from four 
                         different imaging instruments with no data gaps, and we 
                         successfully applied the Comptonization scenario to explain the 
                         broadband X-ray spectra of this source in the low/hard state. For 
                         two of the three observations, our analysis also shows that, 
                         models including Compton reflection can adequately fit the data, 
                         in agreement with previous reports. We show that the observations 
                         can also be modeled by a more detailed Comptonization scheme. 
                         Furthermore, we find the presence of an iron K-edge absorption 
                         feature in one occasion, which confirms what had been previously 
                         observed by Suzaku. Our broadband analysis of this limited sample 
                         shows a rich spectral variability in 1E 1740.7-2942 at the 
                         low/hard state, and we address the possible causes of these 
                         variations. More simultaneous soft/hard X-ray observations of this 
                         system and other black-hole binaries would be very helpful in 
                         constraining the Comptonization scenario and shedding more light 
                         on the physics of these systems.",
                  doi = "10.1051/0004-6361/201323290",
                  url = "http://dx.doi.org/10.1051/0004-6361/201323290",
                 issn = "0004-6361 and 1432-0746",
                label = "scopus 2014-11 CastroDABrMaPoWi:2014:CoThCo",
             language = "en",
           targetfile = "aa23290-13castro.pdf",
        urlaccessdate = "23 abr. 2024"
}