The eclipses of cataclysmic variables. II - U Geminorum

Abstract

view Abstract Citations (51) References (39) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The Eclipses of Cataclysmic Variables. II. U Geminorum Zhang, E. -H. ; Robinson, Edward L. Abstract U Gem is an eclipsing dwarf nova with an orbital period of 4 h 15 m. High-speed, multicolor photometric observations of U Gem in its quiescent state were obtained. A program was used that synthesizes the light curves of cataclysmic variables to derive the properties of U Gem from its eclipses. Using radial velocity curves published by Wade (1981) and by Stover (1981), it was found that i = 69.7 + or - 0.7 deg, M1 = 1.12 + or - 0.13 solar masses, and M2 = 0.53 + or - 0.06 solar mass. The radial temperature distribution across the accretion disk in U Gem shows that the disk is a hollow ring around the white dwarf with R(out) = 0.30 + or - 0.04 and R(in) = 0.12 + or - 0.05 a, where a is the separation of the two stars. The temperature of the ring is 4800 + or - 300 K. The model also reproduces the published infrared light curves and ultraviolet spectral distributions of U Gem. A mass transfer rate of 7.8 x 10 to the -10th solar mass/yr is derived. The structure of the ring around the white dwarf is consistent with the current theories of accretion disk instabilities in dwarf novae. Publication: The Astrophysical Journal Pub Date: October 1987 DOI: 10.1086/165674 Bibcode: 1987ApJ...321..813Z Keywords: Cataclysmic Variables; Dwarf Novae; Eclipsing Binary Stars; Light Curve; Radial Velocity; Stellar Mass Accretion; Computational Astrophysics; High Temperature; Roche Limit; Stellar Luminosity; Ultraviolet Spectra; White Dwarf Stars; Astrophysics; STARS: ACCRETION; STARS: DWARF NOVAE; STARS: ECLIPSING BINARIES; STARS: U GEMINORUM full text sources ADS | data products SIMBAD (1) Related Materials (2) Part 1: 1986ApJ...305..740Z Part 3: 1987AcApS...7..245Z