Swift J1816.7-1613 is a 143 s HMXB Pulsar
ATel #1457; J. P. Halpern, E. V. Gotthelf (Columbia U.)
on 3 Apr 2008; 01:32 UT
Credential Certification: Jules Halpern (jules@astro.columbia.edu)
Subjects: X-ray, Binary, Neutron Star, Pulsar
The transient X-ray source Swift J1816.7-1613 announced
by Krimm et al. (ATel #1456) was also detected serendipitously
in a 16 ks Chandra ACIS observation on 2007 February 11.
Its position is 18h16m42.66s, -16d13'23.4" (J2000),
not consistent with the USNO star mentioned in ATel #1456.
Its spectrum can be fitted by a power law
of photon index Gamma = 1.2+/-0.5 and column density
N_H = (12+/-3)x10^{22} cm^{-2}. The 2-10 keV flux is
4x10^{-12} ergs cm^{-2} s^{-1}. We find a highly pulsed
signal at a barycentric period of 142.9+/-0.2 s.
Evidently a high mass X-ray binary pulsar, this source was
also detected by XMM-Newton at a low flux of 7x10^{-13}
ergs cm^{-2} s^{-1} as 2XMM J181642.7-161320 on 2003 March 8.
