Measurement of the energy emitted from accreting astrophysical systems provides an observational constraint on the plasma processes that may be operating within the disk .
Here we examine the continual time variation over the past six years of the total X-ray flux from the microquasar GRS 1915+105 .
The application of differencing and rescaling techniques to RXTE/ASM data shows that the small amplitude fluctuations scale up to 12–17 days .
A 17-day timescale in the X-ray fluctuations corresponds to half the measured binary orbital period of this system ( 33.5 \pm 1.5 days ) .
While this may be coincidental , it is possible that these two timescales may be linked by , for example , a turbulent cascade in the accretion disk driven by a tidally-induced two-armed spiral shock corotating with the binary system .
Temporal scaling is found only in the ever-present small fluctuations , and not in the intermittent larger-amplitude fluctuations .
This is consistent with the basic model for this source which consists of a steady , cold outer disk and an unstable inner disk .