The X-ray time variability of LSI+61**O303

LSI+61o 303 was discovered in 1977 to be a strong, variable radio source and was proposed to be the counterpart of the COS-B γ-ray source 2CG0135+01. The radio light curve exhibits outbursts whose periodicity corresponds to the optical periodicity of the orbital motion. LSI+61o 303 has been also identified as an x-ray source and an MeV γ-ray source. Long-term continuous x-ray monitoring of LSI+61o 303 by the RXTE/All-Sky-Monitor has now been carried out for a period of 5 years. These data are analyzed and the resulting time variations are summarized. The results are compared to those from radio studies and from a previous x-ray study covering a period of ten months.