PSR J2030+3641: RADIO DISCOVERY AND GAMMA-RAY STUDY OF A MIDDLE-AGED PULSAR IN THE NOW IDENTIFIED FERMI-LAT SOURCE 1FGL J2030.0+3641

Journal Article · Fri Feb 10 00:00:00 EST 2012 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/746/1/39· OSTI ID:22011832

Camilo, F ^[1]; Kerr, M; Romani, R W ^[2]; Ray, P S; Wood, K S ^[3]; Ransom, S M ^[4]; Johnston, S; Keith, M ^[5]; Parent, D ^[6]; DeCesar, M E; Harding, A K; Ferrara, E C ^[7]; Donato, D ^[8]; Saz Parkinson, P M ^[9]; Freire, P C. C.; Guillemot, L; Kramer, M ^[10]

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1. Columbia Astrophysics Laboratory, Columbia University, New York, NY 10027 (United States)
2. W. W. Hansen Experimental Physics Laboratory, Kavli Institute for Particle Astrophysics and Cosmology, Department of Physics and SLAC National Accelerator Laboratory, Stanford University, Stanford, CA 94305 (United States)
3. Space Science Division, Naval Research Laboratory, Washington, DC 20375-5352 (United States)
4. National Radio Astronomy Observatory (NRAO), Charlottesville, VA 22903 (United States)
5. CSIRO Astronomy and Space Science, Australia Telescope National Facility, Epping NSW 1710 (Australia)
6. Center for Earth Observing and Space Research, College of Science, George Mason University, Fairfax, VA 22030 (United States)
7. NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)
8. Department of Physics and Department of Astronomy, University of Maryland, College Park, MD 20742 (United States)
9. Santa Cruz Institute for Particle Physics, Department of Physics and Department of Astronomy and Astrophysics, University of California at Santa Cruz, Santa Cruz, CA 95064 (United States)
10. Max-Planck-Institut fuer Radioastronomie, Auf dem Huegel 69, 53121 Bonn (Germany)

In a radio search with the Green Bank Telescope of three unidentified low Galactic latitude Fermi Large Area Telescope (LAT) sources, we have discovered the middle-aged pulsar J2030+3641 associated with 1FGL J2030.0+3641 (2FGL J2030.0+3640). Following the detection of gamma-ray pulsations using a radio ephemeris, we have obtained a phase-coherent timing solution based on gamma-ray and radio pulse arrival times which spans the entire Fermi mission. With a rotation period of 0.2 s, a spin-down luminosity of 3 Multiplication-Sign 10{sup 34} erg s{sup -1}, and a characteristic age of 0.5 Myr, PSR J2030+3641 is a middle-aged neutron star with spin parameters similar to those of the exceedingly gamma-ray-bright and radio-undetected Geminga. Its gamma-ray flux is 1% that of Geminga, primarily because of its much larger distance, as suggested by the large integrated column density of free electrons, DM = 246 pc cm{sup -3}. We fit the gamma-ray light curve, along with limited radio polarimetric constraints, to four geometrical models of magnetospheric emission, and while none of the fits have high significance some are encouraging and suggest that further refinements of these models may be worthwhile. We argue that not many more non-millisecond radio pulsars may be detected along the Galactic plane that are responsible for LAT sources, but that modified methods to search for gamma-ray pulsations should be productive-PSR J2030+3641 would have been found blindly in gamma rays if only {approx}> 0.8 GeV photons had been considered, owing to its relatively flat spectrum and location in a region of high soft background.

• OSTI ID: 22011832
• Journal Information: Astrophysical Journal, Vol. 746, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
GAMMA RADIATION
LUMINOSITY
NEUTRON STARS
PHOTONS
PULSARS
PULSATIONS
ROTATION
TELESCOPES