2006/06/30 by M. Fiocchi, Mariateresa Fiocchi, A. Bazzano +5 · 1 citation
Physics and Astronomy · #Accretion (finance) #Astronomy #Astrophysical Phenomena and Observations #Astrophysics #Astrophysics and Cosmic Phenomena #Binary number #Black hole (networking) #Black-body radiation #Electron #Low Mass #Neutron star #Nuclear physics #Physics #Pulsars and Gravitational Waves Research #Radiation #Spectral line #Stars #X-ray binary #astro-ph
paper · pdf · doi:10.1086/507321
published as Astrophys.J.651:416-420,2006 · 6 pages, 4 figures, 2 tables. accepted ApJ
arxiv created 2006/06/30 · openalex publication_date 2006/10/27 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We report on the spectral analysis results of the neutron star, atoll type, low mass X-ray Binary 4U1636-53 observed by INTEGRAL and BeppoSAX satellites. Spectral behavior in three different epochs corresponding to three different spectral states has been deeply investigated. Two data set spectra show a continuum well described by one or two soft blackbody plus a Comptonized components with changes in the Comptonizing electrons and black body temperature and the accretion rates, which are typical of the spectral transitions from high to low state. In one occasion INTEGRAL spectrum shows, for first time in this source, a hard tail dominating the emission above 30 keV. The total spectrum is fitted as the sum of a Comptonized component similar to soft state and a power-law component (Gamma=2.76), indicating the presence of a non thermal electron distribution of velocities. In this case, a comparison with hard tails detected in soft states from neutron stars systems and some black hole binaries suggests that a similar mechanism could originate these components in both cases.