CC Direction Spectrum

Starting from solar neutrino direction (see the routine MCG_GET_NEU_DIRECTION), the electron direction is picked either using the double differential cross sections of K. Kubodera or from a 1 - beta/3 cos(theta) distribution obtained from the effective range theory of Ellis and Bahcall, Nucl. Phys. A114 (1968) 636. The former is used if the energy distribution being generated is via the CC interaction, the latter if any other energy distribution has been specified.

If the neutrino type is $\bar{\nu_e}$ and the target is deuterium, the directions of the positron and both neutrons is generated (positron must be generated first). If the target is hydrogen, the directions of the neutron and positron are generated (the neutron must be generated first).

See the routines DIR_CC, DIR_CC_H, and DIR_CC_NEUTRON.