POST-OUTBURST X-RAY FLUX AND TIMING EVOLUTION OF SWIFT J1822.3-1606

Journal Article · Mon Dec 10 04:00:00 EST 2012 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/761/1/66· OSTI ID:22140053

Scholz, P.; Ng, C. -Y.; Livingstone, M. A.; Kaspi, V. M.; Cumming, A.

Swift J1822.3-1606 was discovered on 2011 July 14 by the Swift Burst Alert Telescope following the detection of several bursts. The source was found to have a period of 8.4377 s and was identified as a magnetar. Here we present a phase-connected timing analysis and the evolution of the flux and spectral properties using Rossi X-ray Timing Explorer, Swift, and Chandra observations. We measure a spin frequency of 0.1185154343(8) s{sup -1} and a frequency derivative of -4.3 {+-} 0.3 Multiplication-Sign 10{sup -15} at MJD 55761.0, in a timing analysis that includes significant non-zero second and third frequency derivatives that we attribute to timing noise. This corresponds to an estimated spin-down inferred dipole magnetic field of B {approx} 5 Multiplication-Sign 10{sup 13} G, consistent with previous estimates though still possibly affected by unmodeled noise. We find that the post-outburst 1-10 keV flux evolution can be characterized by a double-exponential decay with decay timescales of 15.5 {+-} 0.5 and 177 {+-} 14 days. We also fit the light curve with a crustal cooling model, which suggests that the cooling results from heat injection into the outer crust. We find that the hardness-flux correlation observed in magnetar outbursts also characterizes the outburst of Swift J1822.3-1606. We compare the properties of Swift J1822.3-1606 with those of other magnetars and their outbursts.

• OSTI ID: 22140053
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 1 Vol. 761; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ASTROPHYSICS
COMPARATIVE EVALUATIONS
CORRELATIONS
COSMIC X-RAY BURSTS
GAMMA ASTRONOMY
KEV RANGE
MAGNETIC FIELDS
MAGNETIC STARS
NEUTRON STARS
PULSARS
SPIN
STAR MODELS
TELESCOPE COUNTERS
VISIBLE RADIATION
X RADIATION
X-RAY DETECTION