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Title: THE EINSTEIN@HOME GAMMA-RAY PULSAR SURVEY. I. SEARCH METHODS, SENSITIVITY, AND DISCOVERY OF NEW YOUNG GAMMA-RAY PULSARS

Abstract

Here, we report on the results of a recent blind search survey for gamma-ray pulsars in Fermi Large Area Telescope (LAT) data being carried out on the distributed volunteer computing system, Einstein@Home. The survey has searched for pulsations in 118 unidentified pulsar-like sources, requiring about 10,000 years of CPU core time. In total, this survey has resulted in the discovery of 17 new gamma-ray pulsars, of which 13 are newly reported in this work, and an accompanying paper. These pulsars are all young, isolated pulsars with characteristic ages between 12 kyr and 2 Myr, and spin-down powers between 10 34 and 4 × 10 36 erg s -1. Two of these are the slowest spinning gamma-ray pulsars yet known. One pulsar experienced a very large glitch $${\rm{\Delta }}f/f\approx 3.5\times {10}^{-6}$$ during the Fermi mission. In this, the first of two associated papers, we describe the search scheme used in this survey, and estimate the sensitivity of our search to pulsations in unidentified Fermi-LAT sources. One such estimate results in an upper limit of 57% for the fraction of pulsed emission from the gamma-ray source associated with the Cas A supernova remnant, constraining the pulsed gamma-ray photon flux that can be produced by the neutron star at its center. Lastly, we also present the results of precise timing analyses for each of the newly detected pulsars.

Authors:
ORCiD logo; ORCiD logo; ORCiD logo; ORCiD logo; ORCiD logo; ORCiD logo; ORCiD logo; ; ORCiD logo; ORCiD logo; ; ORCiD logo; ; ORCiD logo
Publication Date:
Research Org.:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org.:
USDOE
Contributing Org.:
Fermi LAT Collaboration
OSTI Identifier:
1355745
Grant/Contract Number:
AC02-76SF00515
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
The Astrophysical Journal (Online)
Additional Journal Information:
Journal Name: The Astrophysical Journal (Online); Journal Volume: 834; Journal Issue: 2; Journal ID: ISSN 1538-4357
Publisher:
Institute of Physics (IOP)
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS; gamma-rays; stars; pulsars; individual (PSR J0359+5414, PSR J1057-5851, PSR J1350-6225, PSR J1827-1446, PSR J1844-0346)

Citation Formats

Clark, C. J., Wu, J., Pletsch, H. J., Guillemot, L., Allen, B., Aulbert, C., Beer, C., Bock, O., Cuéllar, A., Eggenstein, H. B., Fehrmann, H., Kramer, M., Machenschalk, B., and Nieder, L.. THE EINSTEIN@HOME GAMMA-RAY PULSAR SURVEY. I. SEARCH METHODS, SENSITIVITY, AND DISCOVERY OF NEW YOUNG GAMMA-RAY PULSARS. United States: N. p., 2017. Web. doi:10.3847/1538-4357/834/2/106.
Clark, C. J., Wu, J., Pletsch, H. J., Guillemot, L., Allen, B., Aulbert, C., Beer, C., Bock, O., Cuéllar, A., Eggenstein, H. B., Fehrmann, H., Kramer, M., Machenschalk, B., & Nieder, L.. THE EINSTEIN@HOME GAMMA-RAY PULSAR SURVEY. I. SEARCH METHODS, SENSITIVITY, AND DISCOVERY OF NEW YOUNG GAMMA-RAY PULSARS. United States. doi:10.3847/1538-4357/834/2/106.
Clark, C. J., Wu, J., Pletsch, H. J., Guillemot, L., Allen, B., Aulbert, C., Beer, C., Bock, O., Cuéllar, A., Eggenstein, H. B., Fehrmann, H., Kramer, M., Machenschalk, B., and Nieder, L.. Thu . "THE EINSTEIN@HOME GAMMA-RAY PULSAR SURVEY. I. SEARCH METHODS, SENSITIVITY, AND DISCOVERY OF NEW YOUNG GAMMA-RAY PULSARS". United States. doi:10.3847/1538-4357/834/2/106. https://www.osti.gov/servlets/purl/1355745.
@article{osti_1355745,
title = {THE EINSTEIN@HOME GAMMA-RAY PULSAR SURVEY. I. SEARCH METHODS, SENSITIVITY, AND DISCOVERY OF NEW YOUNG GAMMA-RAY PULSARS},
author = {Clark, C. J. and Wu, J. and Pletsch, H. J. and Guillemot, L. and Allen, B. and Aulbert, C. and Beer, C. and Bock, O. and Cuéllar, A. and Eggenstein, H. B. and Fehrmann, H. and Kramer, M. and Machenschalk, B. and Nieder, L.},
abstractNote = {Here, we report on the results of a recent blind search survey for gamma-ray pulsars in Fermi Large Area Telescope (LAT) data being carried out on the distributed volunteer computing system, Einstein@Home. The survey has searched for pulsations in 118 unidentified pulsar-like sources, requiring about 10,000 years of CPU core time. In total, this survey has resulted in the discovery of 17 new gamma-ray pulsars, of which 13 are newly reported in this work, and an accompanying paper. These pulsars are all young, isolated pulsars with characteristic ages between 12 kyr and 2 Myr, and spin-down powers between 1034 and 4 × 1036 erg s-1. Two of these are the slowest spinning gamma-ray pulsars yet known. One pulsar experienced a very large glitch ${\rm{\Delta }}f/f\approx 3.5\times {10}^{-6}$ during the Fermi mission. In this, the first of two associated papers, we describe the search scheme used in this survey, and estimate the sensitivity of our search to pulsations in unidentified Fermi-LAT sources. One such estimate results in an upper limit of 57% for the fraction of pulsed emission from the gamma-ray source associated with the Cas A supernova remnant, constraining the pulsed gamma-ray photon flux that can be produced by the neutron star at its center. Lastly, we also present the results of precise timing analyses for each of the newly detected pulsars.},
doi = {10.3847/1538-4357/834/2/106},
journal = {The Astrophysical Journal (Online)},
number = 2,
volume = 834,
place = {United States},
year = {Thu Jan 05 00:00:00 EST 2017},
month = {Thu Jan 05 00:00:00 EST 2017}
}

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  • Here, we report the discovery of four gamma-ray pulsars, detected in computing-intensive blind searches of data from the Fermi Large Area Telescope (LAT). The pulsars were found using a novel search approach, combining volunteer distributed computing via Einstein@Home and methods originally developed in gravitational-wave astronomy. The pulsars PSRs J0554+3107, J1422–6138, J1522–5735, and J1932+1916 are young and energetic, with characteristic ages between 35 and 56 kyr and spin-down powers in the range 6 × 10 34—10 36 erg s –1. They are located in the Galactic plane and have rotation rates of less than 10 Hz, among which the 2.1 Hzmore » spin frequency of PSR J0554+3107 is the slowest of any known gamma-ray pulsar. For two of the new pulsars, we find supernova remnants coincident on the sky and discuss the plausibility of such associations. Deep radio follow-up observations found no pulsations, suggesting that all four pulsars are radio-quiet as viewed from Earth. These discoveries, the first gamma-ray pulsars found by volunteer computing, motivate continued blind pulsar searches of the many other unidentified LAT gamma-ray sources.« less
  • We report the discovery of four gamma-ray pulsars, detected in computing-intensive blind searches of data from the Fermi Large Area Telescope (LAT). The pulsars were found using a novel search approach, combining volunteer distributed computing via Einstein@Home and methods originally developed in gravitational-wave astronomy. The pulsars PSRs J0554+3107, J1422–6138, J1522–5735, and J1932+1916 are young and energetic, with characteristic ages between 35 and 56 kyr and spin-down powers in the range 6 × 10{sup 34}—10{sup 36} erg s{sup –1}. They are located in the Galactic plane and have rotation rates of less than 10 Hz, among which the 2.1 Hz spin frequency of PSR J0554+3107 ismore » the slowest of any known gamma-ray pulsar. For two of the new pulsars, we find supernova remnants coincident on the sky and discuss the plausibility of such associations. Deep radio follow-up observations found no pulsations, suggesting that all four pulsars are radio-quiet as viewed from Earth. These discoveries, the first gamma-ray pulsars found by volunteer computing, motivate continued blind pulsar searches of the many other unidentified LAT gamma-ray sources.« less
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