author = "Maiolino, Tais Michele and D'Amico, Fl{\'a}vio and Braga, 
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto 
                         Nacional de Pesquisas Espaciais (INPE)} and {Instituto Nacional de 
                         Pesquisas Espaciais (INPE)}",
                title = "INTEGRAL observations of Scorpius X-1: evidence for Comptonization 
                         up to 200 keV",
              journal = "Astronomy \& Astrophysics",
                 year = "2013",
               volume = "551",
                pages = "L2--L5",
                 note = "Setores de Atividade: Educa{\c{c}}{\~a}o, Pesquisa e 
                         desenvolvimento cient{\'{\i}}fico.",
             keywords = "radiation mechanisms, neutron stars, image processing.",
             abstract = "We have analyzed a long-term database for Sco X-1 obtained with 
                         the telescope IBIS onboard the INTEGRAL satellite in order to 
                         study the hard X-ray behavior of Sco X-1 from 20 up to 200 keV. 
                         Besides the data used for producing of the INTEGRAL catalog of 
                         sources, this is the longest (412 ks) database of IBIS on Sco X-1 
                         up to date. The production of hard X-ray tails in low-mass X-ray 
                         binaries is still a matter of debate. Since most of the fits to 
                         the high-energy part of the spectra are done with powerlaw models, 
                         the physical mechanism for the hard X-ray tail production is 
                         unclear. The purpose of this study is to better constrain those 
                         possible mechanisms. Our main result shows a strong correlation 
                         between the fluxes in the thermal and nonthermal part of Sco X-1 
                         spectra. We, thus, suggest that comptonization of lower energy 
                         photons is the mechanism for producing hard X-ray tails in Sco 
                  doi = "10.1051/0004-6361/201220677",
                  url = "http://dx.doi.org/10.1051/0004-6361/201220677",
                 issn = "0004-6361 and 1432-0746",
                label = "lattes: 0486569206159968 3 MaiolinoDAmiBrag:2013:EvCoUp",
             language = "en",
           targetfile = "aa20677-12.pdf",
        urlaccessdate = "16 jan. 2021"