The Spin-Period History of Intermediate Polars
Solar and Stellar Astrophysics
2020-07-15 v1
Abstract
We report the detailed history of spin-period changes in five intermediate polars (DQ Herculis, AO Piscium, FO Aquarii, V1223 Sagittarii, and BG Canis Minoris) during the 30-60 years since their original discovery. Most are slowly spinning up, although there are sometimes years-long episodes of spin-down. This is supportive of the idea that the underlying magnetic white dwarfs are near spin equilibrium. In addition to the ~40 stars sharing many properties and defined by their strong, pulsed X-ray emission, there are a few rotating much faster (P<80 s), whose membership in the class is still in doubt -- and who are overdue for closer study.
Cite
@article{arxiv.2001.07288,
title = {The Spin-Period History of Intermediate Polars},
author = {Joseph Patterson and Enrique de Miguel and Jonathan Kemp and Shawn Dvorak and Berto Monard and Franz-Josef Hambsch and Tonny Vanmunster and David R. Skillman and David Cejudo and Tut Campbell and George Roberts and Jim Jones and Lewis M. Cook and Greg Bolt and Robert Rea and Joseph Ulowetz and Thomas Krajci and Kenneth Menzies and Simon Lowther and William Goff and William Stein and Matt A. Wood and Gordon Myers and Geoffrey Stone and Helena Uthas and Emir Karamehmetoglu and Jim Seargeant and Jennie McCormick},
journal= {arXiv preprint arXiv:2001.07288},
year = {2020}
}
Comments
PDF, 13 pages, 1 table, 2 figures; submitted, ApJ; more info at http://cbastro.org/