First broad band study of the mysterious source 1E 1743.1–2843

• Published in: Astronomy and astrophysics (Berlin) Vol. 456; no. 3; pp. 1105 - 1108
• Main Authors: Del Santo, M., Sidoli, L., Bazzano, A., Cocchi, M., De Cesare, G., Paizis, A., Ubertini, P.
• Format: Journal Article
• Language: English
• Published: Les Ulis EDP Sciences 01.09.2006
• Subjects: Astronomy; Earth, ocean, space; Exact sciences and technology; radiation mechanisms: general; stars: individual: 1E 1743.1–2843; X-rays: binaries; γ-rays: observations; keV range; Neutron stars; X ray observation; X-rays: binaries; Binary X ray source; Cosmic x-ray sources; Luminosity; stars: individual: 1E 1743.1-2843; radiation mechanisms: general; Spectral analysis; Radiation mechanism; X-ray binary stars; Low-mass stars; γ-rays: observations; Galactic centers
• ISSN: 0004-6361; 1432-0746
• DOI: 10.1051/0004-6361:20065029

Context.In the last years, the persistent source 1E 1743.1–2843 has been observed in the X-rays, but never above 20 keV. In previous works, it was stressed that a possible high energy emission could give further indications on the accreting object nature which remains still unknown. Aims.We present here more than two years of 1E 1743.1–2843 monitoring with INTEGRAL/IBIS as well as public XMM-Newton  and Chandra  X-ray observations. Methods.The temporal study in the 20–40 keV band shows a rather constant flux on few months time scale. Based on this result we have performed the broad-band spectral analysis using EPIC/IBIS non simultaneous data and ACIS-I/IBIS data collected during 2004. Results.In ~2 Ms, we report a detection of 6σ in the energy range 35–70 keV. The first broad-band study (2–70 keV) shows a steep slope (~3) and a black body temperature of 1.7 keV. Conclusions.Combining spectral parameters and discussion about the luminosity evaluations for different possible distances, our conclusions are in favour of a LMXB system with a neutron star at distance higher than the Galactic Centre, even though a firm conclusion can not be stated.