Document Type
Article
Publication Date
8-10-2000
Abstract
We present multiwavelength observations of the newly discovered X-ray transient XTE J1118+480 obtained in the rising phase of the 2000 April outburst. This source is located at unusually high Galactic latitude and in a very low absorption line of sight. This made the first Extreme Ultraviolet Explorer (EUVE) spectroscopy of an X-ray transient outburst possible. Together with our Hubble Space Telescope, Rossi X-Ray Timing Explorer, and United Kingdom Infrared Telescope data, this gives unprecedented spectral coverage. We find the source in the low hard state. The flat IR-UV continuum appears to be a combination of optically thick disk emission and possibly synchrotron, while at higher energies (including EUV), a typical low hard state power law is seen. EUVE observations reveal no periodic modulation, suggesting an inclination low enough that no obscuration by the disk rim occurs. We discuss the nature of the source and this outburst and conclude that it may be more akin to minioutbursts seen in GRO J0422+32 than to a normal X-ray transient outburst.
Publication Source (Journal or Book title)
Astrophysical Journal
Recommended Citation
Hynes, R., Mauche, C., Haswell, C., Shrader, C., Cui, W., & Chaty, S. (2000). The X-ray transient XTE J1118+480: Multiwavelength observations of a low-state minioutburst. Astrophysical Journal, 539 (1 PART 2) https://doi.org/10.1086/312836