Self-inhibiting heat flux

Heat transfer through weakly magnetized diffuse astrophysical plasmas excites whistlers. This leads to electron whistler resonant scattering, a reduction of the electron mean free path, and heat flux inhibition. However, only whistlers propagating at a finite angle to the magnetic field (off-axis) can scatter the heat flux carrying electrons. Thus the level of heat Aux inhibition along the magnetic field lines depends ore the presence of off-axis whistlers. We obtain a solution of the Boltzmann equation with the whistler wave equation and show that if epsilon(th)beta(e) much greater than 10(-4), where epsilon(th) is the thermal collisional Knudsen number and beta(e) is the ratio of the electron pressure to the magnetic energy density, then scattering of heat flux carrying electrons by off-axis whistlers, which are shown to propagate at about 65 degrees, is efficient enough to lead to heat flux inhibition along field lines. The inhibition so obtained is proportional to (epsilon(th)beta(e))(-1).