Radio Supernovae: Circum-Stellar Investigation (C.S.I.) of Supernova Progenitor Stars

摘要

Supernovae (SNe) are among the most energetic phenomena in the Universe. They are integrally linked to many phenomena of importance to modern astrophysics - formation of black holes and neutron stars, at least some types of gamma-ray bursters, powering starburst galaxies, nucleosynthesis, cosmology probes, and distribution of heavy elements and energy into the interstellar medium (ISM). SNe come in two basic types, type Ia (thermonuclear detonation of white dwarfs) and types Ib/Ic/II (resulting from the core-collapse of massive stars). While no radio emission has ever been detected from type Ia SNe, 75% of detected radio SNe are type II and 25% are type Ib/Ic. In the approximately 10, 000 years prior to explosion, the progenitor star is believed to undergo a period of enhanced mass-loss creating a dense region of circumstellar material (CSM) which is propagating outward at 10 km s(exp -1). The modeling of the SN blastwave interaction with the CSM allows the determination of a number of physical properties of SNe from radio observations. Together, Radio and X-Ray measurements provide a deeper insight in the preexplosion evolution of core- collapse supernova progenitors. At present, there are on-going Radio Supernovae (RSN) observing programs on six continents at a variety of facilities.