CHANDRA OBSERVATION OF THE RELATIVISTIC BINARY J1906+0746

Journal Article · Tue Sep 01 04:00:00 EDT 2009 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/702/1/433; COUNTRY OF INPUT: INTERNATIONAL ATOMIC ENERGY AGENCY (IAEA)· OSTI ID:21333834

Kargaltsev, O ^[1]

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1. Department of Astronomy, University of Florida, Bryant Space Science Center, Gainesville, FL 32611 (United States)

PSR J1906+0746 is a young radio pulsar ({tau} = 112 kyr, P = 144 ms) in a tight binary (P{sub orb} = 3.98 hr) with a compact high-mass companion (M{sub comp} {approx_equal} 1.36 M {sub sun}), at the distance of about 5 kpc. We observed this unique relativistic binary with the Chandra Advanced CCD Imaging Spectrometer detector for 31.6 ks. Surprisingly, not a single photon was detected within the 3'' radius from the J1906+0746 radio position. For a plausible range of hydrogen column densities, n {sub H} = (0.5-1) x 10{sup 22} cm{sup -2}, the nondetection corresponds to the 90% upper limit of (3-5) x 10{sup 30} erg s{sup -1} on the unabsorbed 0.5-8 keV luminosity for the power-law model with {gamma} = 1.0-2.0, and {approx}10{sup 32} erg s{sup -1} on the bolometric luminosity of the thermal emission from the neutrons star surface. The inferred limits are the lowest known for pulsars with spin-down properties similar to those of PSR J1906+0746. We have also tentatively detected a puzzling extended structure which looks like a tilted ring with a radius of 1.'6 centered on the pulsar. The measured 0.5-8 keV flux of the feature, {approx}3.1 x 10{sup -14} erg cm{sup -2} s{sup -1}, implies an unabsorbed luminosity of 1.2 x 10{sup 32} erg s{sup -1} (4.5 x 10{sup -4} of the pulsar's E-dot) for n {sub H} = 0.7 x 10{sup 22} cm{sup -2}. If the ring is not a peculiar noise artifact, the pulsar wind nebula around an unusually underluminous pulsar would be the most plausible interpretation.

• OSTI ID: 21333834
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 1 Vol. 702; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
BOLOMETERS
CHARGE-COUPLED DEVICES
HYDROGEN
LUMINOSITY
NEBULAE
NEUTRON STARS
NEUTRONS
PHOTONS
PULSARS
RELATIVISTIC RANGE
SPECTROMETERS