The gamma-ray emitting microquasar LS I+61303

LS I +61 303 is one of the Most Studied X-ray binary systems because of its two Peculiarities: On the one hand being the probable Counterpart of the variable gamma ray source 2CG 135+01 [1, 2] and on the other hand being a periodic radio source [3]. The recent discovery of a radio emitting jet extending ca. 200 AU at both sides of a central core [4] in a] I evidence has shown the occurrence of accretion/ejection processes in this system. However, the radio outbursts do not occur at periastron passage, where the accretion is at its maximum, but several days later. In addition, when the gamma-ray emission of 2CG 135+01 is examined along the orbital phase of LS 1 +61 303 one sees that this emission seems to peak at periastron passage [5]. Here in detail we analyse the trend of the gamma-ray data versus orbital phase and discuss the delay between peaks at gamma-rays and in the radio band within the framework of a two-peak accretion/ejection model proposed by Taylor et al. [6] and further developed by Marti & Paredes [7].