2000/01/27 by Stephen S. Eikenberry, S. Eikenberry, K. Matthews +7 · 1 citation
Physics and Astronomy · #Amplitude #Astronomy #Astrophysical Phenomena and Observations #Astrophysics #Flare #Gamma-ray bursts and supernovae #Infrared #Optics #Physics #Pulsars and Gravitational Waves Research #Telescope #astro-ph
paper · pdf · doi:10.1086/312559
10 pages, 4 figures Accepted for publication in ApJ Letters
arxiv created 2000/01/27 · openalex publication_date 2000/03/20 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We present simultaneous infrared and X-ray observations of the Galactic microquasar GRS 1915+105 using the Palomar 5 m telescope and Rossi X-Ray Timing Explorer on 1998 July 10 UT. Over the course of 5 hr, we observed six faint infrared (IR) flares with peak amplitudes of approximately 0.3-0.6 mJy and durations of approximately 500-600 s. These flares are associated with X-ray soft-dip/soft-flare cycles, as opposed to the brighter IR flares associated with X-ray hard-dip/soft-flare cycles seen in 1997 August by Eikenberry et al. Interestingly, the IR flares begin before the X-ray oscillations, implying an "outside-in" origin of the IR/X-ray cycle. We also show that the quasi-steady IR excess in 1997 August is due to the pileup of similar faint flares. We discuss the implications of this flaring behavior for understanding jet formation in microquasars.