2001/10/22 by A. N. Parmar, T. Oosterbroek, L. Sidoli +2 · 4 citations
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysical Phenomena and Observations #Binary number #Cluster (spacecraft) #Globular cluster #Limit (mathematics) #Orbital elements #Spectral properties #Star cluster #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1051/0004-6361:20011464
5 pages. To appear in A&A
arxiv created 2001/10/22 · openalex publication_date 2001/12/01 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Results of a 2001 March 17-20 BeppoSAX observation of the X-ray binary XB1832-330 located in the globular cluster NGC6652 are presented. In contrast to the majority of luminous globular cluster X-ray sources, the (0.1-200 keV) BeppoSAX spectrum cannot be fit with a disk-blackbody and comptt Comptonization model, unless partial covering is included. This confirms the ASCA detection of partial covering by Mukai & Smale ([CITE]). The best-fit spectral parameters are similar to those of the globular cluster sources with orbital periods of <1 hr, implying that XB1832-330 is also an ultra-compact system. A plausible optical candidate to XB1832-330has recently been discovered by Heinke et al. ([CITE]) which shows evidence for possible 0.92, 2.22, or 4.44 hr periodicities. We find no evidence for any 2-10 keV periodic modulation at any of these periods with a 2σ upper limit to the semi-amplitude of any sinusoid of ≲1.5% .