A Survey of 56 Mid-latitude EGRET Error Boxes for Radio Pulsars

Abstract

We have conducted a radio pulsar survey of 56 unidentified gamma-ray sources from the 3rd EGRET catalog which are at intermediate Galactic latitudes (5 deg. < |b| < 73 deg.). For each source, four interleaved 35-minute pointings were made with the 13-beam, 1400-MHz multibeam receiver on the Parkes 64-m radio telescope. This covered the 95% error box of each source at a limiting sensitivity of about 0.2 mJy to pulsed radio emission for periods P > 10 ms and dispersion measures < 50 pc cm-3. Roughly half of the unidentified gamma-ray sources at |b| > 5 deg. with no proposed active galactic nucleus counterpart were covered in this survey. We detected nine isolated pulsars and four recycled binary pulsars, with three from each class being new. Timing observations suggest that only one of the pulsars has a spin-down luminosity which is even marginally consistent with the inferred luminosity of its coincident EGRET source. Our results suggest that population models, which include the Gould belt as a component, overestimate the number of isolated pulsars among the mid-latitude Galactic gamma-ray sources and that it is unlikely that Gould belt pulsars make up the majority of these sources. However, the possibility of steep pulsar radio spectra and the confusion of terrestrial radio interference with long-period pulsars (P > 200 ms) having very low dispersion measures (< 10 pc cm-3, expected for sources at a distance of less than about 1 kpc) prevent us from strongly ruling out this hypothesis. Our results also do not support the hypothesis that millisecond pulsars make up the majority of these sources. Non-pulsar source classes should therefore be further investigated as possible counterparts to the unidentified EGRET sources at intermediate Galactic latitudes.

24 pages, including 4 figures and 3 tables. Accepted for publication in ApJ

References in corpus (2)

• The ATNF Pulsar Catalogue
• Discovery of 14 radio pulsars in a survey of the Magellanic Clouds

Cited by in corpus (20)

• Shapiro delay measurement of a two solar mass neutron star
• Constraints on the Emission Geometries and Spin Evolution of Gamma-ray Millisecond Pulsars
• The MeerTime Pulsar Timing Array -- A Census of Emission Properties and Timing Potential
• NICER X-ray Observations of Seven Nearby Rotation-Powered Millisecond Pulsars
• Pulsed Gamma-rays from PSR J2021+3651 with the Fermi Large Area Telescope
• A Search for Fast Radio Bursts Associated with Gamma-Ray Bursts
• NICER Detection of Thermal X-ray Pulsations from the Massive Millisecond Pulsars PSR J0740+6620 and PSR J1614-2230
• Early evolutionary tracks of low-mass stellar objects in modified gravity
• Cooling process of brown dwarfs in Palatini f(R) gravity
• Lithium abundance is a gravitational model dependent quantity
• Searches for Shapiro delay in seven binary pulsars using the MeerKAT telescope
• Metric-affine gravity effects on terrestrial (exo-)planets profiles
• Jupiter and jovian (exo)-planets in Palatini $f(\bar{R})$ gravity
• Planetary seismology as a test of modified gravity proposals
• Non-Singular Gravitational Collapse through Modified Heisenberg Algebra
• Giant planet formation in Palatini gravity
• Non-homogeneous exoplanets in metric-affine gravity
• A 350-MHz Green Bank Telescope Survey of Unassociated Fermi LAT Sources: Discovery and Timing of Ten Millisecond Pulsars
• Magnetic braking of Ap/Bp stars: an alternative formation mechanism of compact intermediate-mass binary pulsars
• Radio timing constraints on the mass of the binary pulsar PSR J1528-3146