Saturday, 26 January 2013

Photonics Space Lighting up the Stars: Novae studied.

nova  is a cataclysmic nuclear explosion in a white dwarf star. It is caused by the accretion of hydrogen on to the surface of the star, which ignites and starts nuclear fusion in a runaway manner. Novae are not to be confused with supernovae or luminous red novae.

Some of the nuclear physics of the explosive events known as novae is beginning to be understood. Explosive nuclear processes make previously unobserved stars visible for a short period of time.  An international  team of scientists carefully measured the nuclear structure of the radioactive neon produced in the explosion. As a result there is much less uncertainty in how quickly one of the key nuclear reactions occur and the final abundance of radioactive isotopes produced

Two images of Nova Cygni 1992 taken by the Hubble Space Telescope. (Credit: F. Paresce, R. Jedrzejewski (STScI), NASA/ESA}

Led by the University of York, UK, and Universitat Politècnica de Catalunya and the Institut d'Estudis Espacials de Catalunya, Spain, their findings have been reported in the journal Physical Review Letters.

Dr Alison Laird, from the University of York's Department of Physics, said: "The explosion is fundamentally driven by nuclear processes. The radiation related to the decay of isotopes -- in particular that from an isotope of fluorine -- is actively being sought by current and future gamma ray observing satellite missions as it provides direct insight into the explosion.
"However, to be interpreted correctly, the nuclear reaction rates involved in the production of the fluorine isotope must be known. We have demonstrated that previous assumptions about key nuclear properties are incorrect and have improved."

Photonic Space