A New Determination of the Spectra and Luminosity Function of Gamma-Ray Millisecond Pulsars

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In this article, we revisit the gamma-ray emission observed from millisecond pulsars and globular clusters.

• Based on 5.6 years of data from the Fermi Gamma-Ray Space Telescope, we report gamma-ray spectra for 61 millisecond pulsars, finding most to be well fit by a power-law with an exponential cutoff, producing to a spectral peak near ~1-2 GeV (in $E^2 dN/dE$ units).
• Additionally, while most globular clusters exhibit a similar spectral shape, we identify a few with significantly softer spectra.
• We also determine the gamma-ray luminosity function of millisecond pulsars using the population found in the nearby field of the Milky Way, and within the globular cluster 47 Tucanae.