This catalog summarizes 117 high-confidence 0.1 GeV gamma-ray pulsar detections using three years of data acquired by the Large Area Telescope (LAT) on the Fermi satellite. Half are neutron stars discovered using LAT data through periodicity searches in gamma-ray and radio data around LAT unassociated source positions. The 117 pulsars are evenly divided into three groups: millisecond pulsars, young radio-loud pulsars, and young radio-quiet pulsars. We characterize the pulse profiles and energy spectra and derive luminosities when distance information exists. Spectral analysis of the off-peak phase intervals indicates probable pulsar wind nebula emission for four pulsars, and off-peak magnetospheric emission for several young and millisecond pulsars. We compare the gammaray properties with those in the radio, optical, and X-ray bands. We provide flux limits for pulsars with no observed gamma-ray emission, highlighting a small number of gamma-faint, radio-loud pulsars. The large, varied gamma-ray pulsar sample constrains emission models. Fermi's selection biases complement those of radio surveys, enhancing comparisons with predicted population distributions.
XSS J12270−4859 is an X-ray binary associated with the Fermi LAT gammaray source 1FGL J1227.9−4852. In 2012 December, this source underwent a transition where the X-ray and optical luminosity dropped and the spectral signatures of an accretion disc disappeared. We report the discovery of a 1.69 millisecond pulsar (MSP), PSR J1227−4853, at a dispersion measure of 43.4 pc cm −3 associated with this source, using the GMRT at 607 MHz. This demonstrates that, post-transition, the system hosts an active radio MSP. This is the third system after PSR J1023+0038 and PSR J1824−2452I showing evidence of state switching between radio MSP and low-mass X-ray binary (LMXB) states.We report timing observations of PSR J1227−4853 with the GMRT and Parkes, which give a precise determination of the rotational and orbital parameters of the system. The companion mass measurement of 0.17 to 0.46 M suggests that this is a redback system. PSR J1227−4853 is eclipsed for about 40% of its orbit at 607 MHz; with additional short-duration eclipses at all orbital phases. We also find that the pulsar is very energetic, with a spin-down luminosity of ∼ 10 35 erg s −1 . We report simultaneous imaging and timing observations with the GMRT, which suggests that eclipses are caused by absorption, rather than dispersion smearing or scattering.
In a search with the Parkes radio telescope of 56 unidentified Fermi-LAT gamma-ray sources, we have detected 11 millisecond pulsars (MSPs), 10 of them discoveries, of which five were reported in Kerr et al. (2012). We did not detect radio pulsations from another six pulsars now known in these sources. We describe the completed survey, which included multiple observations of many targets done to minimize the impact of interstellar scintillation, acceleration effects in binary systems, and eclipses. We consider that 23 of the 39 remaining sources may still be viable pulsar candidates. We present timing solutions and polarimetry for five of the MSPs, and gamma-ray pulsations for PSR J1903−7051 (pulsations for five others were reported in the second Fermi-LAT catalog of gamma-ray pulsars). Two of the new MSPs are isolated and five are in > 1 d circular orbits with 0.2-0.3 M ⊙ presumed white dwarf companions. PSR J0955−6150, in a 24 d orbit with a ≈ 0.25 M ⊙ companion but eccentricity of 0.11, belongs to a recently identified class of eccentric MSPs. PSR J1036−8317 is in an 8 hr binary with a > 0.14 M ⊙ companion that is probably a white dwarf. PSR J1946−5403 is in a 3 hr orbit with a > 0.02 M ⊙ companion with no evidence of radio eclipses.
We present a summary of the Fermi Pulsar Search Consortium (PSC), an international collaboration of radio astronomers and members of the Large Area Telescope (LAT) collaboration, whose goal is to organize radio follow-up observations of Fermi pulsars and pulsar candidates among the LAT γ-ray source population. The PSC includes pulsar observers with expertise using the world's largest radio telescopes that together cover the full sky. We have performed very deep observations of all 35 pulsars discovered in blind frequency searches of the LAT data, resulting in the discovery of radio pulsations from four of them. We have also searched over 300 LAT γ-ray sources that do not have strong associations with known γ-ray emitting source classes and have pulsar-like spectra and variability characteristics. These searches have led to the discovery of a total of 43 new radio millisecond pulsars (MSPs) and four normal pulsars. These discoveries greatly increase the known population of MSPs in the Galactic disk, more than double the known population of so-called 'black widow' pulsars, and contain many promising candidates for inclusion in pulsar timing arrays.
Using the Giant Metrewave Radio Telescope (GMRT) we performed deep observations to search for radio pulsations in the directions of unidentified Fermi Large Area Telescope (LAT) γ-ray sources. We report the discovery of an eclipsing black-widow millisecond pulsar, PSR J1544+4937, identified with the uncataloged γ-ray source Fermi J1544.2+4941. This 2.16 ms pulsar is in a 2.9 -2hours compact circular orbit with a very low-mass companion (M c > 0.017M ). At 322 MHz this pulsar is found to be eclipsing for 13% of its orbit, whereas at 607 MHz the pulsar is detected throughout the low-frequency eclipse phase. Variations in the eclipse ingress phase are observed, indicating a clumpy and variable eclipsing medium. Moreover, additional short-duration absorption events are observed around the eclipse boundaries. Using the radio timing ephemeris we were able to detect γ-ray pulsations from this pulsar, confirming it as the source powering the γ-ray emission.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.