Do Recurrent Novae Become Type Ia Supernovae? (Abstract)

Volume 30 number 2 (2002)

Bradley E. Schaefer

Abstract

(Abstract only) Astrophysics has long had an important problem in identifying the progenitor systems of Type Ia supernovae, with a prominent possibility being Recurrent Novae. Recurrent Novae (like U Sco and CI Aql) are binaries in which mass is being poured onto a white dwarf near the Chandrasekhar mass limit. If the white dwarf is gaining mass over each eruption cycle, then it must inevitably become a supernova, but on average, the eruption might throw off more mass than is being accreted. With approximately known mass accretion rates, the question then becomes, “How much mass is ejected during an eruption?” I have been timing eclipses of U Sco and CI Aql since 1987, so I have very accurate orbital periods before their recent eruptions (1999 and 2000, respectively). Now I am measuring their orbital periods after the eruptions to determine the period change and hence the ejected mass. All together, this program will determine whether the white dwarfs in U Sco and CI Aql will become supernovae, and hence solve the old progenitor problem.