PI: Thomas Harrison, New Mexico State U., firstname.lastname@example.org
Address: Astronomy Department, Box 30001/Department 4500, Las Cruces, NM, 88003-8001 USA
Title: Characterizing the L-dwarf Donor and the System Parameters of WZ Sagittae
Abstract: As cataclysmic variables evolve, the binary orbital period shrinks, as does the secondary star. Eventually, the donor has a mass that cannot sustain hydrogen burning, and it becomes a brown dwarf. Such an object expands upon further mass loss, and thus the orbital period of the CV must increase. This is the so-called "period bounce". WZ Sge is the leading candidate for being a period bouncer. We have used Keck NIRSPEC data to derive a spectral type of L2 to L7 for the donor star, and have produced a radial velocity curve for this object. Our radial velocity for the donor shows that the white dwarf in WZ Sge is quite massive compared to those found in the majority of CVs. We propose observations to more tightly constrain the spectral type of its L-dwarf donor, as well as derive a more precise radial velocity curve for this object and its (Vsini) rotation rate. With these data we will be able to completely specify the masses of the components in this binary. This result will provide new insight into the evolution of cataclysmic variables, and determine whether short period CVs are potential SNIa progenitors.
Program Type: Standard/Galactic
Run 1 (2016B): GEM-NQ/GNIRS -- 3.6hrs band 3 (GN-2016B-Q-69)
National Optical Astronomy Observatory, 950 North Cherry Avenue, P.O. Box 26732, Tucson, Arizona 85726, Phone: (520) 318-8000, Fax: (520) 318-8360