Presupernovae as powerful neutrino sources detectable by next neutrino experiments M. Kutschera, A. Odrzywołek, M. Misiaszek Ustroń 2009

Neutrino astrophysics group Institute of Physics, Jagellonian University, Kraków, Poland: A.Odrzywołek, M. Misiaszek, M.K. References to our papers: arXiv Neutrino spectra available at

Research summary: Spectra of neutrinos from stars at late stages of thermonuclear burning (presupernovae) are found This allows us to predict counting rates in various neutrino detectors Presupernovae seem to be detectable by next generation of neutrino detectors

Stars with initial mass (ZAMS) M>9M sol after red giant phase: –ignite carbon –develope iron core –end life as core-collapse supernovae –example: 15 M sol :

Nearby candidate: - Betelgeuse in ORION constellation - distance 130 pc

After carbon ignition neutrino-cooled stars Photon luminosity much less L<<L ν than neutrino luminosity. -photon luminosity constant after carbon ignition -neutrino luminosity grows by many orders!

Strong temperature growth in the core

Can neutrino experiments detect presupernovae?

Pair annihilation dominant Antineutrino flux from pair annihilation crucial ! Different than for the Sun (only neutrinos)

High density – neutrino and antineutrino spectra differ

Near the collapse: –Total flux grows as L ν ~T c 9 –Mean neutrino energy grows

Predictions for various detectors

Range one day before collapse (various detectors)

Presupernova neutrinos vs geoneutrinos

Nuclear reactions produce more neutrinos ν e than pair annihilation More than 1000 nuclei must be included

Weak nuclear reactions: neutrinos excess

Comparison with solar neutrinos

REAL NEUTRINO ASTRONOMY STARTS