BROADBAND TIMING OF THE ULTRALUMINOUS X-RAY SOURCES IN M82: ORBITAL DECAY comma QPOS

The galaxy M82 harbors two notable ultraluminous Xray sources (ULX): M82 X2,the archetipal pulsating ultraluminous Xray source (PULX), and M82 X1, a IMBHcandidate. The extreme luminosity of ULXs, and the observation of strong windsfrom these sources, suggests that these sources are undergoing stronglysuperEddington accretion. The supply of matter that powers these accretingsystems is likely to come from Roche Lobe overflow from a more massive companionstar, and should produce changes of orbital period observable in time scales ofvirgulyears. This program aims at detecting this orbital period derivative throughpulsar timing in M82 X2, and study in detail the quasiperiodic oscillationsfrom both ULXs. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]