2018/02/01 by Zhuo-li Yu, Xiao-jie Xu, Xiang-Dong Li +4 · 16 citations
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysical Phenomena and Observations #Bulge #Cataclysmic variable star #Flux (metallurgy) #Mass ratio #Pulsars and Gravitational Waves Research #Spectral line #White dwarf #astro-ph.HE
paper · pdf · doi:10.3847/1538-4357/aaa47d
published in The Astrophysical Journal 853(2), 182 (IOP Publishing) · 11 pages, 4 figures, accepted for publication in The Astrophysical Journal
openalex publication_date 2018/02/01 · openalex created_date 2018/02/23 · arxiv created 2018/04/03 · arxiv updated 2018/04/04 · openalex updated_date 2026/08/05
Abstract The mean white dwarf (WD) mass in the Galactic bulge cataclysmic variables (CVs) was measured by applying the shock temperature-WD mass correlation of magnetic cataclysmic variables (mCVs) to the Galactic bulge X-ray emission (GBXE) spectra. However, the resulting mean WD mass is lower than that of the local CVs. This discrepancy could be explained by the dominating sources in the GBXE, which are non-mCVs instead of mCVs. In this work, we conduct a thorough investigation of the X-ray spectra of local DNe from the Suzaku archives and derive semi-empirical correlations between the shock temperature T max , the flux ratio of Fe xxvi –Ly α to Fe xxv –He α lines, and WD mass for quiescent, nonmagnetic CVs. By applying these correlations to the GBXE, we derive the average WD mass of CVs in the Galactic bulge to be 0.81 ± 0.07 M ⊙ . This value is consistent with previous optical measurements of WD mass in local CVs.