Far Ultraviolet Spectroscopy of Old Novae I. V603 Aquila

Area of Science:

• * Astrophysics
• * Stellar Evolution
• * Novae

Background:

• * V603 Aquilae is a fast old nova observed 90 years post-outburst.
• * Previous studies lacked precise distance and accretion disk parameters.
• * Far-ultraviolet (FUV) archival data from IUE, HST, and FUSE offer insights into its current state.

Purpose of the Study:

• * To determine the mass transfer rate in the old nova V603 Aquilae.
• * To model its accretion disk using synthetic spectral analysis.
• * To constrain the white dwarf mass and system parameters.

Main Methods:

• * Synthetic spectral analysis of archival FUV observations (IUE, HST, FUSE).
• * Utilization of Hubble FGS parallax for accurate distance.
• * Modeling of non-truncated, optically thick accretion disks.

Main Results:

• * Estimated mass transfer rate of ~1.1 x 10^-10 M☉/yr for both FUSE and HST spectra (assuming 1.2 M☉ white dwarf).
• * Mass accretion rate doubles for a lower white dwarf mass of 0.8 M☉.
• * Consistent results obtained when combining FUSE and HST spectra.

Conclusions:

• * The study provides crucial parameters for understanding the evolution of old novae.
• * The derived mass transfer rate offers insights into the accretion processes in V603 Aquilae.
• * Further implications for nova remnant evolution and white dwarf binary systems are discussed.