Multiwavelength observations revealing the outbursts of the two soft X-ray transients XTE J1859+226 and XTE J1118+480

S. Chaty*, C. A. Haswell, R. I. Hynes, C. R. Shrader, W. Cui, C. W. Mauche, A. J. Norton, J. E. Solheim, R. Ostensen, T. R. Geballe, Z. Ioannou, A. R. King

*Corresponding author for this work

Research output: Contribution to journalConference articlepeer-review

1 Citation (Scopus)


We report here on multiwavelength observations of the two new soft X-ray transients (SXTs) XTE J1859+226 and XTE J1118+480, which we observed with HST/RXTE/UKIRT. For XTE J1118+480 we also used EUVE since it is located at a very high galactic latitude and suffers from very low extinction. The two sources exhibited very different behaviour. XTE J1859+226 seems quite normal and therefore a good object for testing the accretion mechanisms in place during the outbursts, XTE J1118+480 is much more unusual because it exhibits i) a low X-ray to optical ratio and ii) a strong non-thermal contribution in the radio to optical domain, which is likely to be due to synchrotron emission. We concentrate here on the near-infrared (NIR) and optical observations of these two systems.

Original languageEnglish
Pages (from-to)491-494
Number of pages4
JournalEuropean Space Agency, (Special Publication) ESA SP
Issue number459
Publication statusPublished - Sep 2001
Externally publishedYes
Event4th Integral Workshop -Exploring the Gamma-Ray Universe-2000 - Alicante, Spain
Duration: Sep 4 2000Sep 8 2000


  • Infrared: stars
  • Stars: individual: XTE J1859+226
  • X-rays: stars
  • XTE J1118+480

ASJC Scopus subject areas

  • Aerospace Engineering
  • Space and Planetary Science

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