Spin-down rate of 1E 2259+586 from RXTE observation

Baykal A., Swank J., Strohmayer T., Stark M.

ASTRONOMY & ASTROPHYSICS, vol.336, no.1, pp.173-176, 1998 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 336 Issue: 1
  • Publication Date: 1998
  • Journal Name: ASTRONOMY & ASTROPHYSICS
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.173-176
  • Keywords: accretion, accretion disks, pulsars : individual : 1E 2259+586, X-rays : stars, X-RAY PULSARS, EXTRAORDINARY, 1E-2259+586, ACCRETION, TORQUE
  • Middle East Technical University Affiliated: Yes

Abstract

We present new X-ray observations of the X-ray pulsar 1E 2259+586, obtained during March 1997, with the Rossi X-Ray Timing Explorer (RXTE). We have measured the pulse frequency derivative (nu) over dot = (-1.08 +/- 0.04) x 10(-14) Hz s(-1) from pulse arrival times obtained in a sequence of 5 observations spread over one month. This (nu) over dot is consistent with the long term spin-down trend. We also found that the observed X-ray luminosity is consistent with that measured at quiescent X-ray flux levels by previous missions. Our observations imply that 1E 2259 +/- 586 was spinning down steadily without exhibiting any stochastic torque noise fluctuations during the month covered by our observations.