Chandra X-ray Observations of the Spiral Galaxy M81
  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. 
Douglas A. Swartz (USRA/MSFC), Kajal K. Ghosh (USRA/MSFC), Michael L.   McCollough (USRA/MSFC), Thomas G. Pannuti (MIT), All...