NuSTAR DISCOVERY OF AN UNUSUALLY STEADY LONG-TERM SPIN-UP OF THE Be BINARY 2RXP J130159.6-635806
ABSTRACT We present spectral and timing analyses of Nuclear Spectroscopic Telescope Array (NuSTAR) observations of the accreting X-ray pulsar 2RXP J130159.6-635806. The source was serendipitously observed during a campaign focused on the gamma-ray binary PSR B1259-63 and was later targeted for a ded...
Saved in:
Published in | The Astrophysical journal Vol. 809; no. 2; pp. 1 - 8 |
---|---|
Main Authors | , , , , , , , , , , , , , , , , |
Format | Journal Article |
Language | English |
Published |
United Kingdom
The American Astronomical Society
20.08.2015
|
Subjects | |
Online Access | Get full text |
Cover
Loading…
Summary: | ABSTRACT We present spectral and timing analyses of Nuclear Spectroscopic Telescope Array (NuSTAR) observations of the accreting X-ray pulsar 2RXP J130159.6-635806. The source was serendipitously observed during a campaign focused on the gamma-ray binary PSR B1259-63 and was later targeted for a dedicated observation. The spectrum has a typical shape for accreting X-ray pulsars, consisting of a simple power law with an exponential cutoff starting at ∼7 keV with a folding energy of keV. There is also an indication of the presence of a 6.4 keV iron line in the spectrum at the significance level. NuSTAR measurements of the pulsation period reveal that the pulsar has undergone a strong and steady spin-up for the last 20 years. The pulsed fraction is estimated to be , and is constant with energy up to 40 keV. The power density spectrum shows a break toward higher frequencies relative to the current spin period. This, together with steady persistent luminosity, points to a long-term mass accretion rate high enough to bring the pulsar out of spin equilibrium. |
---|---|
Bibliography: | ApJ99201 Compact Objects ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 0004-637X 1538-4357 1538-4357 |
DOI: | 10.1088/0004-637X/809/2/140 |