GAMMA-RAY LINE EMISSION, NUCLEAR DESTRUCTION AND NEUTRON-PRODUCTION IN HOT ASTROPHYSICAL PLASMAS - THE DEUTERIUM BOILER AS A GAMMA-RAY SOURCE

In hot astrophysical plasmas with ion temperatures high enough for nuclear excitation (≥ 1011 K) inelastic spallation reactions can proceed at a higher or similar rate leading to nuclei destruction during the stationary high-temperature plasma formation time. Therefore the nuclei manage to be excited before destruction, but on the average not more than once. As a result the nuclear line luminosity is strongly depressed and does not exceed 10-3 - 10-4 of the total luminosity which is associated mainly with the electron component of the plasma. In the quasi-stationary sources of hard radiation (e.g. accretion discs) a proton-neutron plasma is formed due to nuclear destruction without a noticeable content of heavy nuclei. In the two-temperature plasma (Ti > Te) the nucleons lose their energy mainly through elastic collisions. Besides, the nucleons radiatively cool due to neutron capture by protons (with deuterium production) and bremsstrahlung during the proton-neutron scattering. The possibility of neutron evaporation from the two-temperature accretion discs is discussed. © 1984 Royal Astronomical Society. Provided by the NASA Astrophysics Data System.