Temporal study of GRS 1915+105 with rms-flux relation:The importance of magnetic activities in the corona

摘要

The rms-flux relations for some observations of GRS 1915+105 are studied.The rms-flux relations of the light curves in only one state,state C or state A,can be described by the simple non-linear model provided Zhang;we thus interpret that such a linear relation reflects the relative importance of magnetic instability for X-ray emission in the corona of the system,compared to the thermal viscous instability for the X-ray emission in the accretion disk.The rms-flux relations for state B are very scattered,possibly because of the dominance of thermal viscous instability for the X-ray emission in the accretion disk.The complex rms-flux relations for the observations of transitions between two or three states are caused by the combination of the different rms-flux relations of these states.The underlying physical processes are the combination of magnetic topology in the corona and thermal viscous instability in the accretion disk.