2000/06/21 by L. Sidoli, Sidoli, L., A. N. Parmar +3
Decision Sciences · Physics and Astronomy · #Astrophysical Phenomena and Observations #Astrophysics (astro-ph) #FOS: Physical sciences #Scientific Measurement and Uncertainty Evaluation #X-ray Spectroscopy and Fluorescence Analysis #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/0006307
10 pages, 8 figures, accepted for publication in A&A Main Journal
arxiv created 2000/06/21 · openalex publication_date 2000/06/21 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
Results of a 1999 November 16--17 BeppoSAX observation of the low-mass X-ray binary X2127+119 located in the globular cluster NGC7078 are presented. The system is believed to be one where the central neutron star is normally obscured by the accretion disk, and only X-rays scattered into our line of sight by an extended accretion disk corona (ADC) are observed. The 0.1--10 keV lightcurve is energy dependent and shows two partial eclipses separated by the 17.1 hr orbital period. The 0.1--100 keV spectrum is unusually complex, but can be successfully modeled using a partially covered power-law and disk-blackbody model. Together with a column consistent with the interstellar value to NGC7078, about 60% of the source is covered by an additional column of 1E22 atom/cm2. The absorbed component may be X-rays that pass through the outer layers of the accretion disk. The energy dependent intensity variations by a factor of ~2 may be modeled as due to a changing normalization of the disk-blackbody. None of the other spectral parameters appear to clearly depend on luminosity. The same spectral model is also able to fit an archival ASCA spectrum.