G. Raffelt et D. Seckel, SELF-CONSISTENT APPROACH TO NEUTRAL-CURRENT PROCESSES IN SUPERNOVA CORES, Physical review. D. Particles and fields, 52(4), 1995, pp. 1780-1799
The problem of neutral-current processes (neutrino scattering, pair em
ission, pair absorption, axion emission, etc.) in a nuclear medium can
be separated into an expression representing the phase space of the w
eakly interacting probe, and a set of dynamic structure functions of t
he medium. For a nonrelativistic medium we reduce the description to t
wo structure functions S-A(omega) and S-V(omega) of the energy transfe
r, representing the axial-vector and vector interactions. S-V is well
determined by the single-nucleon approximation while S-A may be domina
ted by multiply interacting nucleons. Unless the shape of S-A(omega) c
hanges dramatically at high densities, scattering processes always dom
inate over pair processes for neutrino transport or the emission of ri
ght-handed states. Because the emission of right-handed neutrinos and
axions is controlled by the same medium response functions, a consiste
nt constraint on their properties from consideration of supernova cool
ing should use the same structure functions for both neutrino transpor
t and exotic cooling mechanisms.