22Ne(a, n)25Mg reaction in CONe mantle of massive stars at high temperatures

Abstract

The effectiveness of22Ne (a, n)25Mg reaction as a neutron source is examined at high temperatures 0.8⩽T 9⩽3.0 (T 9 is the temperature in units of 109 K). An assembly consisting of12C,16O, and22Ne is considered at the end of helium burning in some massive stars. Alpha particles necessary for this neutron producing reaction are assumed to be due to reactions involving12C and16O nuclei. Assuming22Ne as the only neutron absorber, the number density of neutrons is calculated. The mantles outside the cores of massive stars are possibly the physical sites for these reactions.