AX J1910.7+0917: the slowest X-ray pulsar [HEAP]

http://arxiv.org/abs/1705.01791


Pulsations from the high mass X-ray binary AXJ1910.7+0917 were discovered during Chandra observations performed in 2011 (Israel et al. 2016). We report here more details on this discovery and discuss the source nature. The period of the X-ray signal is P=36200+/-110s, with a pulsed fraction, PF, of 63+/-4%. Given the association with a massive B-type companion star, we ascribe this long periodicity to the rotation of the neutron star, making AXJ1910.7+0917 the slowest known X-ray pulsar. We report also on the spectroscopy of XMM-Newton observations that serendipitously covered the source field, resulting in an highly absorbed (column density almost reaching 1e23cm-2), power law X-ray spectrum. The X-ray flux is variable on a timescale of years, spanning a dynamic range >60. The very long neutron star spin period can be explained within a quasi-spherical settling accretion model, that applies to low luminosity, wind-fed, X-ray pulsars.

Read this paper on arXiv…

L. Sidoli, G. Israel, P. Esposito, et. al.
Fri, 5 May 17
24/60

Comments: 6 pages, 3 figures. Accepted for publication in Mon. Not. R. Astron. Soc. (Accepted 2017 May 3. Received 2017 May 3; in original form 2017 April 6)