The broad band X–ray spectrum of the black hole candidate GRS 1758–258
Istituto di Astrofisica Spaziale e Fisica Cosmica – Sezione di Milano “G. Occhialini" – CNR via Bassini 15, 20133 Milano, Italy
Corresponding author: L. Sidoli, email@example.com
Accepted: 8 April 2002
We present the results of a BeppoSAX observation of the black hole candidate GRS 1758–258 carried out in 1997, while the source was in its low/hard state. The X–ray spectrum, simultaneously observed over the broad energy range from 0.1 to 200 keV, can be well described by a Comptonized emission model with electron temperature keV and optical depth (spherical geometry), although a cut-off power-law and a reflection model cannot be excluded. Additionally, a broad iron line at 6.4 keV with equivalent width eV has been marginally detected. The 0.1–200 keV luminosity is erg s-1 for an assumed distance of 8 kpc. The soft and hard luminosities are such that the source falls inside the so-called “burster box". No evidence for a soft excess is present.
Key words: accretion, accretion disks / stars: individual: GRS 1758-258 / X-rays: general
© ESO, 2002