Change in accretion torque in the binary accreting pulsar 4U 1626− 67

Abstract:

We describe two years of BATSE observations of the 7.66 s accreting pulsar 4U 1626−67. Power spectral analysis and period folding techniques with the 1.024 s resolution DISCLA data from the Large Area Detectors (LDAs) have provided nearly continuous monitoring of 4U 1626−67 in the 20–60 keV range. The long term frequency history of the source shows nearly constant spin‐down at a range of ḟ≊−7.4×10−13 s−2, in contrast to the continuous spin‐up (with ḟ≊8.5×10−13 s−2) observed previously. We discuss the implications of these results for accretion torque theories and compare this behavior to that of GX 1+4.

Año de publicación:

1994

Keywords:

Fuente:

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