Multiwavelength Characterization of the High Mass X-ray Binary
  Population of M31
  We present our analysis of high quality high mass X-ray binary (HMXB)
candidates in M31 selected from point-source optical-counterpart candidates
from the Chandra-PHAT survey catalog. We fit the spectral energy distributions
(SEDs) of optical counterpart candidates using the Bayesian Extinction and
Stellar Tool (BEAST). We used the best-fit luminosity, effective temperature,
radius and dust reddening for the companion stars in combination with the local
star formation history, dust maps of M31, published X-ray spectral fits from
XMM-Newton observations, IR colors, and Chandra X-ray hardness ratios to
determine our best sample of HMXB candidates. The age distribution of the HMXB
sample appears peaked between 10 and 50 Myr, consistent with findings in other
nearby galaxies. Using the age distribution and mean SFR, we find that 80$-$136
HMXBs were produced per unit of star formation rate over the last 50 Myr and
89$-$163 HMXBs were produced per unit of star formation rate over the last 80
Myr, if we expand the assumed age limit beyond the lifetimes of single massive
stars. We also calculate the HMXB production rate (HMXBs/M$_{\odot}$) over
time, which ranges from $7 \times 10^{-7}$ to $4 \times 10^{-6}$
HMXBs/M$_{\odot}$ over the last 80 Myr, in agreement with both theoretical
predictions and measured production rates in other galaxies.
