[Previous] | [Session 33] | [Next]
A.H. Rots (CfA), V.M. Kaspi (MIT), R.N. Manchester (ATNF), M. Bailes (Swinburn U.T.)
We have monitored the stable pulsar B1509-58 in the 2-100 keV X-ray band with RXTE since the start of that mission, in January 1996. The X-ray pulse lags the radio pulse by 0.30 ±0.01 in phase and there is no indication of this lag's depending on energy.
Starting from the radio timing ephemeris, we have derived a single X-ray timing ephemeris that fits the entire monitoring period, using the pulse frequency and its first, second, and third derivatives. This provides a value of 2.85 for the breaking index, in agreement with earlier determinations, but the third derivative is too high to be consistent with a simple spin-down law.
Of special interest are the timing residuals which either require a higher order po;ynomial fit or exhibit a (quasi?) periodic behavior with a period of about 710 days and an amplitude of 3 to 4 ms.
This work has been supported by NASA grant NAG5-7335.
The author(s) of this abstract have provided an email address for comments about the abstract: arots@head-cfa.harvard.edu