The Third Fermi Large Area Telescope Catalog of Gamma-ray Pulsars

TL;DR

This paper presents the third Fermi LAT catalog of gamma-ray pulsars, including 294 newly identified pulsars and candidates, expanding the known population significantly and providing detailed spectral and timing properties.

Contribution

It reports the discovery of approximately 340 gamma-ray pulsars and candidates, including new millisecond pulsars and binary systems, with detailed spectral and luminosity analyses, enhancing the understanding of gamma-ray pulsar populations.

Findings

Over 340 gamma-ray pulsars and candidates identified, representing 10% of all known pulsars.

Gamma-ray spectral properties correlate with pulsar spindown power, approaching synchrotron radiation shapes at low energies.

Half of the gamma-ray pulsars are young, with some undetected in radio, showing broader Galactic latitude distribution.

Abstract

We present 294 pulsars found in GeV data from the Large Area Telescope (LAT) on the Fermi Gamma-ray Space Telescope. Another 33 millisecond pulsars (MSPs) discovered in deep radio searches of LAT sources will likely reveal pulsations once phase-connected rotation ephemerides are achieved. A further dozen optical and/or X-ray binary systems co-located with LAT sources also likely harbor gamma-ray MSPs. This catalog thus reports roughly 340 gamma-ray pulsars and candidates, 10% of all known pulsars, compared to $\leq 11$ known before Fermi. Half of the gamma-ray pulsars are young. Of these, the half that are undetected in radio have a broader Galactic latitude distribution than the young radio-loud pulsars. The others are MSPs, with 6 undetected in radio. Overall, >235 are bright enough above 50 MeV to fit the pulse profile, the energy spectrum, or both. For the common two-peaked profiles, the gamma-ray peak closest to the magnetic pole crossing generally has a softer spectrum. The spectral energy distributions tend to narrow as the spindown power $\dot E$ decreases to its observed minimum near $10^{33}$ erg s$^{-1}$, approaching the shape for synchrotron radiation from monoenergetic electrons. We calculate gamma-ray luminosities when distances are available. Our all-sky gamma-ray sensitivity map is useful for population syntheses. The electronic catalog version provides gamma-ray pulsar ephemerides, properties and fit results to guide and be compared with modeling results.