* Astronomy

Title: V3885 Sagittarius: a Comparison with a Range of Standard Model Accretion Disks
Authors: Albert P. Linnell, Patrick Godon, Ivan Hubeny, Edward M. Sion, Paula Szkody, Paul E. Barrett

A ~\chi²  analysis of standard model accretion disk synthetic spectrum fits to combined $FUSE$ and STIS spectra of V3885 Sagittarius, on an absolute flux basis, selects a model that accurately represents the observed SED. Calculation of the synthetic spectrum requires the following system parameters. The cataclysmic variable secondary star period-mass relation calibrated by Knigge in 2007 sets the secondary component mass. A mean white dwarf (WD) mass from the same study, that is consistent with an observationally-determined mass ratio, sets the adopted WD mass of 0.7 Solar masses, and the WD radius follows from standard theoretical models. The adopted inclination, i=65°, is a literature consensus, and is subsequently supported by ~\chi²  analysis. The mass transfer rate is the remaining parameter to set the accretion disk T_{eff} profile, and the Hipparcos parallax constrains that parameter to solar masses=5.0±2.0x10^-9 Solar masses {yr}^-1 by a comparison with observed spectra. The fit to the observed spectra adopts the contribution of a 57,000±5000K WD. The model thus provides realistic constraints on Solar mass and T_{eff} for a large Solar mass system above the period gap.

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