Swift XRT flux measurement of the magnetar SGR 0501+4516
ATel #4374; T. Enoto (GSFC, RIKEN), T. Sakamoto (Aoyama Univ.), M. Morii (Tokyo Institute of Technology), Y. E. Nakagawa (Waseda Univ.), J. Takata (HKU), and K. Makishima (The University of Tokyo)
on 13 Sep 2012; 22:29 UT
Credential Certification: Teruaki Enoto (teruaki.enoto@gmail.com)
Subjects: X-ray, Soft Gamma-ray Repeater
A Swift follow-up observation of the transient magnetar SGR 0501+4516 was performed on September 8 with a 2 ks exposure, following the MAXI novae alert on 2012 September 6 (ID=6176073538, warning) that reported a possible X-ray enhancement from a position (RA, DEC)=(75.308, 45.965), 0.69 degrees away from this magnetar location.
A simple absorbed power-law model gives a 2-10 keV absorbed X-ray flux of 8.7(+3.6, -3.2)e-13 erg cm-2 s-1, with a hydrogen column density of N_H ~ 1e+22 cm2 and a spectral photon index of 3.6. The measured flux is consistent within errors with the most recently measured XRT 2-10 keV flux, 9.6(+2.1, -2.0)e-13 erg cm-2 s-1, on 2010 February 21 (two and half years before the present follow-up observation), but is brighter than a naive extrapolation of the downward trend of this source following its 2008 outburst (Atel #1676 and subsequent reports).
We thank the Swift team for their rapid scheduling of the observation.
