2006/11/30 by A. Papitto, T. Di Salvo, L. Burderi +3 · 4 citations
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysical Phenomena and Observations #Astrophysics and Star Formation Studies #astro-ph
paper · pdf · doi:10.1111/j.1365-2966.2006.11359.x
published as Mon.Not.Roy.Astron.Soc.375:971-976,2007 · 7 pages, 4 figures, Accepted for publication by MNRAS
arxiv created 2006/11/30 · openalex publication_date 2007/01/25 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We present a precise timing analysis of the accreting millisecond pulsar XTE J1814−338 during its 2003 outburst, observed by RXTE. A full orbital solution is given for the first time; Doppler effects induced by the motion of the source in the binary system were corrected, leading to a refined estimate of the orbital period, Porb= 15 388.7229(2) s, and of the projected semimajor axis, a sin i/c= 0.390633(9) light-second. We could then investigate the spin behaviour of the accreting compact object during the outburst. We report here a refined value of the spin frequency (ν= 314.356 108 79(1) Hz) and the first estimate of the spin frequency derivative of this source while accreting . This spin-down behaviour arises when both the fundamental frequency and the second harmonic are taken into consideration. We discuss this in the context of the interaction between the disc and the quickly rotating magnetosphere, at accretion rates sufficiently low to allow a threading of the accretion disc in regions where the Keplerian velocity is slower than the magnetosphere velocity. We also present indications of a jitter of the pulse phases around the mean trend, which we argue results from movements of the accreting hotspots in response to variations of the accretion rate.