Disk‐Jet Coupling in the Low‐Mass X‐Ray Binary 4U 1636−53 fromINTEGRALObservations

Mariateresa Fiocchi, Angela Bazzano, Pietro Ubertini, Pierre Jean
2006 Astrophysical Journal  
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
more » ... l 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.
doi:10.1086/507321 fatcat:6yvv6adz25gmplbihjingk4npa