The Accretion Ejection Instability : Observationnal Tests

The Accretion Ejection Instability (hereafter AEI), has been proposed to explain, the energy and angular momentum transport from the innermost parts of accretion disks in the X-Ray Binaries (XB), (permitting thus the accretion), toward a coronal medium, which is thought to be the base of jets (Tagger & Pellat, 1999; Tagger 1999, Varni\`ere et al., 2000; Corbel, phD Thesis, 1999). The low frequency QPO often observed in the XB's, are theorically predicted with the AEI; furthemore theorical calculations in a strong gravitationnal field (Varni\`ere, Rodriguez & Tagger, 2000) lead to an unexpected behavior when looking at the QPO frequency variations vs. the disk radius. We the analysed a set of public observations of GRO J1655-40 and GRS 1915+105, in order to verify the theorical predictions. We 'll see in particular that they have different behavior, and will point out interesting differences between the two sources when the model gives unrealistic low values of the disk radius.