Chandra observations of SGR 1627-41 near quiescence

Abstract

We report on an observation of SGR 1627-41 made with the Chandra X-ray Observatory on 2011 June 16. Approximately three years after its outburst activity in 2008, the source's flux has been declining, as it approaches its quiescent state. For an assumed power-law spectrum, we find that the absorbed 2--10 keV flux for the source is $1.0_{-0.2}^{+0.3}\times 10^{-13}ergc{m}^{-2}{s}^{-1}$ with a photon index of $2.9\pm 0.8$ ($N_H=1.0\times 10^{23}$ cm^{-2}). This flux is approximately consistent with that measured at the same time after the source's outburst in 1998. With measurements spanning 3 years after the 2008 outburst, we analyze the long-term flux and spectral evolution of the source. The flux evolution is well described by a double exponential with decay times of 0.5 $\pm$ 0.1 and 59 $\pm$ 6 days, and a thermal cooling model fit suggests that SGR 1627-41 may have a hot core ($T_{c}2\times 10^8$ K). We find no clear correlation between flux and spectral hardness as found in other magnetars. We consider the quiescent X-ray luminosities of magnetars and the subset of rotation-powered pulsars with high magnetic fields ($B>10^{13}$ G) in relation to their spin-inferred surface magnetic-field strength, and find a possible trend between the two quantities.

25 pages, 5 figures, 3 tables. Accepted for publication in ApJ

References in corpus (28)

• The strongest cosmic magnets: Soft Gamma-ray Repeaters and Anomalous X-ray Pulsars
• Transient pulsed radio emission from a magnetar
• Corona of Magnetars
• Untwisting magnetospheres of neutron stars
• Magnetar-like Emission from the Young Pulsar in Kes 75
• Discovery of luminous pulsed hard X-ray emission from anomalous X-ray pulsars 1RXS J1708-4009, 4U 0142+61 and 1E 2259+586 by INTEGRAL and RXTE
• The Prelude to and Aftermath of the Giant Flare of 2004 December 27: Persistent and Pulsed X-ray Properties of SGR 1806-20 from 1993 to 2005
• The Compact X-ray Source 1E 1547.0-5408 and the Radio Shell G327.24-0.13: A New Proposed Association between a Candidate Magnetar and a Candidate Supernova Remnant
• Recent Progress on Anomalous X-ray Pulsars
• Evidence for Heating of Neutron Stars by Magnetic Field Decay
• Discovery of Pulsations and a Possible Spectral Feature in the X-ray Emission from Rotating Radio Transient J1819-1458
• Detailed high-energy characteristics of AXP 1RXS J170849-400910 - Probing the magnetosphere using INTEGRAL, RXTE and XMM-Newton
• Exciting the Magnetosphere of the Magnetar CXOU J164710.2-455216 in Westerlund 1
• The first XMM-Newton observations of the Soft Gamma-ray Repeater SGR 1900+14
• The 2008 May burst activation of SGR 1627-41
• From outburst to quiescence: the decay of the transient Anomalous X-ray Pulsar XTE J1810-197
• X-ray and Near-IR Variability of the Anomalous X-ray Pulsar 1E 1048.1-5937: From Quiescence Back to Activity
• Using Chandra to Unveil the High-Energy Properties of the High-Magnetic Field Radio Pulsar J1119-6127
• XMM-Newton observations of CXOU J010043.1-721134: the first deep look at the soft X-ray emission of a magnetar
• SGR 1806-20 about two years after the giant flare: Suzaku, XMM-Newton and INTEGRAL observations
• Chandra Observations of the High-Magnetic-Field Radio Pulsar J1718-3718
• XMM-Newton observation of the Soft Gamma Ray Repeater SGR 1627-41 in a low luminosity state
• XMM-Newton discovery of 2.6 s pulsations in the soft gamma-ray repeater SGR 1627-41
• Swift and Chandra confirm the intensity-hardness correlation of the AXP 1RXS J170849.0-400910
• Spin-down rate and inferred dipole magnetic field of the soft gamma-ray repeater SGR 1627-41
• Quiet but still bright: XMM-Newton observations of the soft gamma-ray repeater SGR 0526-66
• XMM-Newton X-ray Observation of the High-Magnetic-Field Radio Pulsar PSR J1734--3333
• Long term spectral variability in the soft gamma ray repeater SGR 1900+14

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