2001/08/14 by S. Chaty, C. A. Haswell, Chaty, S. +7
Engineering · Physics and Astronomy · #Astrophysical Phenomena and Observations #Astrophysics (astro-ph) #FOS: Physical sciences #Mechanics and Biomechanics Studies #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/0108242
4 pages, 2 figures, 2001, SF2A, Lyon, May 28-June 1st, Societe Francaise d'Astronomie et d'Astrophysique (eds), EDPS Conference Series in Astronomy & Astrophysics, in press. 1 reference added
openalex publication_date 2001/08/14 · arxiv created 2001/08/15 · arxiv updated 2009/12/01 · openalex created_date 2022/10/04 · openalex updated_date 2026/07/28
We report multiwavelength observations of the two soft X-ray transients (SXTs) XTE J1859+226 and XTE J1118+480, which we observed with HST, RXTE and UKIRT. The two sources exhibited very different behaviour. XTE J1859+226 showed a thermal-viscous disc instability outburst modified by irradiation. XTE J1118+480, which we also observed with EUVE since it is located at a very high galactic latitude and suffers from very low extinction, is much more unusual. It exhibits i) a low X-ray to optical flux ratio and ii) a strong non-thermal contribution throughout the spectrum, which is likely to be due to synchrotron emission. We concentrate here on their evolution in the course of their outbursts.