Magnetic features in the spectrum of Her X-1

✍ Scribed by D.E. Gruber; W.A. Heindl; R.E. Rothschild; R. Staubert; J. Wilms

• Book ID: 104355521
• Publisher: Elsevier Science
• Year: 1999
• Tongue: English
• Weight: 317 KB
• Volume: 69
• Category: Article
• ISSN: 0920-5632
• DOI: 10.1016/s0920-5632(98)00204-7

✦ Synopsis

Spectral study of three observations of the accreting X-ray pulsar Her X-1 during RXTE observing round 1 show that the values of two spectral parameters, the cut energy and the cyclotron line centroid, appear to be much more stable than for the other shape parameters. These two parameters have been closely linked to the strength of the teraganss magnetic field above the polar cap of the neutron star. The RMS stability of 1% implies an equal constraint on the average value of the magnetic field at the site of emission, and in a dipole field this constrains the average height of emission to within 50 meters. It may be possible to discriminate between emission in the very thin neutron star atmosphere and in an extensive accretion mound. *We acknowledge NASA grant NAG5-3272