Discovery of 46.6 s X-ray Pulsations from the Candidate for IGR J22534+6243
ATel #4240; J. P. Halpern (Columbia U.)
on 6 Jul 2012; 21:29 UT
Credential Certification: Jules Halpern (jules@astro.columbia.edu)
Subjects: X-ray, Gamma Ray, Neutron Star, Pulsar
Landi et al. (ATel #4166) proposed a Swift XRT source as the counterpart of the
INTEGRAL/IBIS source IGR J22534+6243 (Krivonos et al. 2012, arXiv:1205.3941).
I found that this X-ray source was also detected in five archival Chandra
ACIS observations. Although far off axis, its position is seen to be consistent with
that of 2MASS J22535512+6243368 as proposed in ATel #4166. The bright IR
counterpart, as well as the X-ray spectral properties derived by
Landi et al., suggest that this is a reddened high-mass X-ray binary.
The five Chandra observations, on 2009 April 16,28 and May 3,7,8, have
exposure times of 23-28 ks each. Analyzing them separately, I find in
each one a significant periodic signal in the proposed counterpart
at a consistent barycentric period of 46.673(4) s. This represents
the mean value of the five observations and the typical uncertainty
on each one. The period is also present in the 72 ks of Swift
XRT data spanning 2006 April 21-24, but with P = 46.6149(3) s.
The complex pulse profiles are illustrated below.
Folded X-ray Light Curves