%0 Journal Article
%4 dpi.inpe.br/plutao/2013/05.31.18.47
%2 dpi.inpe.br/plutao/2013/05.31.18.47.22
%@doi 10.1051/0004-6361/201220677
%@issn 0004-6361
%@issn 1432-0746
%F lattes: 0486569206159968 3 MaiolinoDAmiBrag:2013:EvCoUp
%T INTEGRAL observations of Scorpius X-1: evidence for Comptonization up to 200 keV
%D 2013
%9 journal article
%A Maiolino, Tais Michele,
%A D'Amico, Flávio,
%A Braga, João,
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@electronicmailaddress tais.maiolino@das.inpe.br
%@electronicmailaddress damico@das.inpe.br
%@electronicmailaddress joao.braga@das.inpe.br
%B Astronomy & Astrophysics
%V 551
%P L2-L5
%K radiation mechanisms, neutron stars, image processing.
%X 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 X-1.
%@language en
%3 aa20677-12.pdf
%O Setores de Atividade: Educação, Pesquisa e desenvolvimento científico.