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Chandra X-ray Observations of the Spiral Galaxy M81

Douglas A. Swartz·Kajal K. Ghosh·Michael L. McCollough·Thomas G. Pannuti·Allyn F. Tennant·Kinwah Wu
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Abstract

A Chandra X-Ray Observatory ACIS-S imaging observation is used to study the population of X-ray sources in the nearby Sab galaxy M81 (NGC 3031). A total of 177 sources are detected with 124 located within the D25 isophote to a limiting X-ray luminosity of 3e36 ergs/cm2/s. Source positions, count rates, luminosities in the 0.3-8.0 keV band, limiting optical magnitudes, and potential counterpart identifications are tabulated. Spectral and timing analysis of the 36 brightest sources are reported including the low-luminosity active galactic nucleus, SN 1993J, and the Einstein-discovered ultra-luminous X-ray source X6.

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Douglas A. Swartz, Kajal K. Ghosh, Michael L. McCollough, Thomas G. Pannuti, Allyn F. Tennant, Kinwah Wu. 2002-06-11. Chandra X-ray Observations of the Spiral Galaxy M81. https://doi.org/10.1086/345084

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