Poster abstract details
HST/COS and VLT/X-shooter Spectroscopy of the Cataclysmic Variable IR Com
Abstract
Constraining the masses of white dwarf (WD) in Cataclysmic Variables (CVs) is fundamental in order to understand if CV WDs could grow in mass, giving rise to type Ia Supernova explosions. With this purpose, we are carrying out a systematic study of a sample of 32 CVs with HST/COS and VLT/X-shooter. We here present the observations for the CV IR Com. From phase-resolved X-shooter observations we measure the radial velocity amplitudes of the M-dwarf ($K_2 = 453.2 \pm 1.1\,$km
s$^{\mathrm{-1}}$) and the WD ($K_1 = 73.9 \pm 12.0\,$km s$^{\mathrm{-1}}$). The eclipse of the white dwarf is resolved in the time-tagged COS ultraviolet data, and allows us to set the binary inclination in the range $75\degree < i < 90 \degree$. This constraint, combined with the mass ratio computed from the measured radial velocity amplitudes, implies that the white dwarf mass lies in the range $ 1.13\,M_{\odot} < M_{\mathrm{wd}} < 1.26\,M_{\odot}$. The analysis of the VLT and HST data of IR Com demonstrates that we can accurately measure the WD masses, and once done for the full sample we will be able to answer the question whether accreting CV WDs grow in mass.
s$^{\mathrm{-1}}$) and the WD ($K_1 = 73.9 \pm 12.0\,$km s$^{\mathrm{-1}}$). The eclipse of the white dwarf is resolved in the time-tagged COS ultraviolet data, and allows us to set the binary inclination in the range $75\degree < i < 90 \degree$. This constraint, combined with the mass ratio computed from the measured radial velocity amplitudes, implies that the white dwarf mass lies in the range $ 1.13\,M_{\odot} < M_{\mathrm{wd}} < 1.26\,M_{\odot}$. The analysis of the VLT and HST data of IR Com demonstrates that we can accurately measure the WD masses, and once done for the full sample we will be able to answer the question whether accreting CV WDs grow in mass.