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arXiv · 0903.4864

Chandra Observation of Quiescent Low-Mass X-ray Binaries in the Globular Cluster NGC 6304

S. Guillot·R. E. Rutledge·E. F. Brown·G. G. Pavlov·V. E. Zavlin
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Abstract

This paper presents the analysis of candidate quiescent low mass xray binarie (qLMXBs) observed during a short Chandra/ACIS observation of the globular cluster (GC) NGC 6304. Two out of the three candidate qLMXBs of this cluster, XMMU 171433-292747 and XMMU 171421-292917, lie within the field of view. This permits comparison with the discovery observation of these sources. The one in the GC core -- XMMU 171433-292747 -- is spatially resolved into two separate X-ray sources, one of which is consistent with a pure H-atmosphere qLMXB, and the other is an X-ray power-law spectrum source. These two spectral components separately account for those observed from XMMU 171433-292747 in its discovery observation. We find that the observed flux and spectral parameters of the H-atmosphere spectral components are consistent with the previous observation, as expected from a qLMXB powered by deep crustal heating. XMMU 171421-292917 also has neutron star atmosphere spectral parameters consistent with those in the XMM-Newton observation and the observed flux has decreased by a factor 0.54^{+0.30}_{-0.24}.

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S. Guillot, R. E. Rutledge, E. F. Brown, G. G. Pavlov, V. E. Zavlin. 2009-06-16. Chandra Observation of Quiescent Low-Mass X-ray Binaries in the Globular Cluster NGC 6304. https://doi.org/10.1088/0004-637x%2F699%2F2%2F1418

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