Accretion column eclipses in the X-ray pulsars GX 1+4 and RX J0812.4-3114

Details Accretion column eclipses in the X-ray pulsars GX 1+4 and RX J0812.4-3114 Accretion column eclipses in the X-ray pulsars GX 1+4 and RX J0812.4-3114

2000-10-25

arxiv.org/abs/astro-ph/0010523v3

Mon.Not.Roy.Astron.Soc. 325 (2001) 419

Astronomy and Astrophysics

Astrophysics

7 pages, 5 figures, accepted by MNRAS. Included references

Scientific paper

10.1046/j.1365-8711.2001.04467.x

Sharp dips observed in the pulse profiles of three X-ray pulsars (GX 1+4, RX J0812.4-3114 and A 0535+26) have previously been suggested to arise from partial eclipses of the emission region by the accretion column occurring once each rotation period. We present pulse-phase spectroscopy from Rossi X-ray Timing Explorer satellite observations of GX 1+4 and RX J0812.4-3114 which for the first time confirms this interpretation. The dip phase corresponds to the closest approach of the column axis to the line of sight, and the additional optical depth for photons escaping from the column in this direction gives rise to both the decrease in flux and increase in the fitted optical depth measured at this phase. Analysis of the arrival time of individual dips in GX~1+4 provides the first measurement of azimuthal wandering of a neutron star accretion column. The column longitude varies stochastically with standard deviation 2-6 degrees depending on the source luminosity. Measurements of the phase width of the dip both from mean pulse profiles and individual eclipses demonstrates that the dip width is proportional to the flux. The variation is consistent with that expected if the azimuthal extent of the accretion column depends only upon the Keplerian velocity at the inner disc radius, which varies as a consequence of the accretion rate Mdot.

Affiliated with

Also associated with

No associations

Rating

Accretion column eclipses in the X-ray pulsars GX 1+4 and RX J0812.4-3114 does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Accretion column eclipses in the X-ray pulsars GX 1+4 and RX J0812.4-3114, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Accretion column eclipses in the X-ray pulsars GX 1+4 and RX J0812.4-3114 will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-105235