Abstract:
Z sources are the brightest low-mass X-ray binaries (LMXB) believed to
contain magnetized neutron stars. They trace a '2' shaped track in theil X-ray
colour-colour diagram. It is thought that the accretion rate increases systematically
along this track. According to 'unified model' proposed to explain combined spectral
and timing properties of this class of sources, the systematic variation with accretion
rate of spectral parameters such as the optical depth and the comptonizution parameter
can explain the '2' shaped track. We have made detailed spectral and timing analysis
of the 2 source OX 349+2 using RXTE archival data of the period 29 September
to 13 October 1998 to investigate the spectral variations along the 2 track. We
discuss the results in this paper.
