2017/10/20 by Jayashree Roy, Manojendu Choudhury, P. C. Agrawal · 6 citations
Physics and Astronomy · #Absorption (acoustics) #Astrophysical Phenomena and Observations #Astrophysics and Cosmic Phenomena #Cyclotron #Cyclotron resonance #Flux (metallurgy) #Line (geometry) #Magnetic field #Phase (matter) #Scattering #Solar and Space Plasma Dynamics #Spectral line #astro-ph.HE
paper · pdf · doi:10.3847/1538-4357/aa8d67
published in The Astrophysical Journal 848(2), 124 (IOP Publishing)
openalex publication_date 2017/10/20 · arxiv created 2017/11/05 · arxiv updated 2017/11/07 · openalex created_date 2017/11/10 · openalex updated_date 2026/08/05
Abstract The Rossi X-Ray Timing Explorer /Proportional Counter Array (PCA) observations of IGR J19294+1816 covering two outburst episodes are reported. The first outburst happened during MJD 54921-54925 (2009 C.E.), and the second one happened during MJD 55499–55507 (2010 C.E.). In both cases, the PCA observations were made during the decay phase of the outburst, with the source exhibiting a temporal and spectral evolution with the change in flux. At the bright flux level, an absorption feature at 35.5 keV is detected in the spectra, which may be attributed to the Cyclotron Resonance Scattering Feature corresponding to a magnetic field of Gauss. This is also detected at a lower significance in two other observations. In addition, an Fe line emission at 6.4 keV is prominently detected during the highest flux. X-ray pulsations are detected in 9 out of 10 observations; no pulsations were found in the observation with the lowest flux level. During this observation with the lowest flux, the pulsation phenomenon becomes detectable only at the soft X-ray bands.