The Detection of Photospheric X-Ray Pulsations from PG 1159-035 with EXOSAT
Winget, D. E.; Barstow, M. A.; Holberg, J. B.; Grauer, A. D.
United Kingdom, United States
Abstract
The detection of soft X-ray pulsations from the hot, helium-rich, degenerate object, PG 1159-035 is reported. These observations, obtained with the Low Energy experiment on EXOSAT, show the presence of large-amplitude soft X-ray (44-150 A) pulsations analogous to several of the low-amplitude, nonradial, g-mode pulsations which are observed in the optical. These soft X-ray pulsations, with periods of 516 s, 524 s, and 539 s, arise from the photosphere of PG 1159-035 and constitute the first observations of stellar atmospheric pulsational phenomena in the X-ray band.