Astronomy and Astrophysics – Astrophysics
Scientific paper
2002-04-29
Astronomy and Astrophysics
Astrophysics
ApJ, in press. Movie: http://rocinante.colorado.edu/~mnowak/movie.html
Scientific paper
10.1086/340757
During a previous outburst phase, the neutron star 4U 2129+47 exhibited evidence for a spatially extended corona via broad, partial X-ray eclipses occurring periodically on the 5.24 hr orbit. Since 1983, however, 4U 2129+47 has entered a quiescent state several orders of magnitude fainter. We have performed a 37 ksec Chandra observation of 4U 2129+47 to determine whether an extended coronal structure also exists in quiescence. Total eclipses are found, and the rapidity of the eclipse ingress and egress are used to place upper limits on the size of the X-ray source. The spectrum is comprised of a soft component plus a fairly hard power law tail. The former is seen to be sinusoidally modulated over the orbital period in a manner consistent with neutral column variations, possibly due to the interaction of an accretion stream with a (small) disk about the neutron star. We fit realistic atmosphere models to the soft spectra, and comment on the consistency of the spectra with cooling neutron star models. It has been suggested that the 4U 2129+47 system is a hierarchical triple, with the outer body being an F star. We use differential astrometry to show that the X-ray point source and F star are spatially coincident to within 0.1". We further compare newly determined upper limits for the extrinsic neutral column to the reddening of the F star. Finally, we discuss how future X-ray observations can further constrain models of quiescent neutron star emission, as well as directly verify the triple hypothesis.
Begelman Mitchell
Heinz Sebastian
Nowak Michael
No associations
LandOfFree
Hiding in Plain Sight: Chandra Observations of the Quiescent Neutron Star 4U 2129+47 in Eclipse 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 Hiding in Plain Sight: Chandra Observations of the Quiescent Neutron Star 4U 2129+47 in Eclipse, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Hiding in Plain Sight: Chandra Observations of the Quiescent Neutron Star 4U 2129+47 in Eclipse will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-625834