Searching a Thousand Radio Pulsars for Gamma-Ray Emission
Abstract
Identifying as many gamma-ray pulsars as possible in the Fermi Large Area Telescope (LAT) data helps test pulsar emission models by comparing predicted and observed properties for a large, varied sample with as little selection bias as possible. It also improves extrapolations from the observed population to estimate the contribution of unresolved pulsars to the diffuse gamma-ray emission. We use a recently developed method to determine the probability that a given gamma-ray photon comes from a known position in the sky, convolving the photon's energy with the LAT's energy-dependent point-spread function, without the need for an accurate spatial and spectral model of the gamma-ray sky around the pulsar. The method is simple and fast and, importantly, provides probabilities, or weights, for gamma-rays from pulsars too faint for phase-integrated detection. We applied the method to over a thousand pulsars for which we obtained rotation ephemerides from radio observations, and discovered gamma-ray pulsations from 16 pulsars, 12 young and 4 recycled. PSR J2208 4056 has spindown power E = 8 x 1032 erg s-1, about three times lower than the previous observed gamma-ray emission "deathline." PSRs J2208 4056 and J1816-0755 have radio interpulses, constraining their geometry and perhaps enhancing their gamma-ray luminosity. We discuss whether the deathline is an artifact of selection bias due to the pulsar distance.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 23, 2019
- Accession Number
- AD1099654
Entities
People
- A. D. Cameron
- A. G. Lyne
- B. W. Stappers
- Charlotte Sobey
- D. A. Smith
- F. Camilo
- I. Cognard
- L. Guillemot
- M. J. Keith
- Matthew Kerr
- Michael Kramer
- P. Bruel
- P. Weltevrede
- R. N. Manchester
- Rebecca C. Shannon
- Sen Dai
- Shawn F. Johnson
- T. J. Johnson
Organizations
- United States Naval Research Laboratory