XMM-Newton Detection of the 7.8 s Pulsar XTE J1829-098
ATel #319; J. P. Halpern, E. V. Gotthelf (Columbia U.)
on 11 Aug 2004; 02:36 UT
Credential Certification: Jules Halpern (jules@astro.columbia.edu)
An outburst of the newly discovered 7.8 s pulsar XTE J1829-098 (Markwardt et al., ATEL #317)
is seen in an unpublished XMM-Newton Galactic Plane Survey observation taken on 2003 March 27,
when the source had a barycentric pulse period of 7.840+/-0.002 s and a count rate of 4.5 counts/s
in the EPIC pn camera. Its position is R.A. = 18h29m44.0s, Decl. = -09d51'23" (J2000). The standard
90% confidence position uncertainty is 4".
The spectrum is fitted, but not very well (chisquare = 48.5 for 33 d.o.f.),
by a power law of photon index 0.9+/-0.2
and N_H = (6+/-1)x10^{22} cm^{-2}. The 2-10 keV flux is 5.6x10^{-11} ergs cm^{-2} s^{-1}.
In comparison with the total Galactic 21 cm column in this direction of 1.8x10^{22} cm^{-2}, this
suggests that most of the absorption is intrinsic to the source. In additional XMM pointings
at the same field, the source was not detected on 2002 March 27 and 2003 September 13.
See Hands, Warwick, Watson, & Helfand, MNRAS, 351, 31-56 (2004) for details of the XMM-Newton Galactic Plane Survey.
