1999/04/22 by P. T. Życki, P. Zycki, Chris Done +3 · 3 citations
Physics and Astronomy · #Astrophysical Phenomena and Observations #Astrophysics and Cosmic Phenomena #Gamma-ray bursts and supernovae #astro-ph
paper · pdf · doi:10.1046/j.1365-8711.1999.02885.x
published as Mon.Not.Roy.Astron.Soc. 309 (1999) 561 · 15 pages, uses mn.sty, submitted to MNRAS
arxiv created 1999/04/22 · openalex publication_date 1999/11/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/04
We reanalyse archival Ginga data of the soft X-ray transient source GS 2023+338 covering the beginning of its 1989 May outburst. The source showed a number of rather unusual features: very high and apparently saturated luminosity, dramatic flux and spectral variability (often on ∼1 s time-scale), and generally very hard spectrum, with no obvious soft thermal component characteristic for soft/high state. We describe the spectrum obtained at the maximum of flux and we demonstrate that it is very different from spectra of other soft X-ray transients at similar luminosity. We confirm previous suggestions that the dramatic variability was the result of heavy and strongly variable photoelectric absorption. We also demonstrate that for a short time the spectrum of the source did look like a typical soft/high state spectrum but that this coincided with very heavy absorption.