Abstract
The previous analysis by Barkat & Wheeler of the convective Urca neutrino-loss process in degenerate, convective, quasi-static, carbon-burning cores omitted specific consideration of the role of the kinetic energy flux. The arguments of Barkat & Wheeler that steady state composition gradients exist are correct, but chemical equilibrium does not result in net cooling. Barkat & Wheeler included a "work" term that effectively removed energy from the total energy budget that could have come only from the kinetic energy, which must remain positive. Consideration of the kinetic energy in the thermodynamics of the convective Urca process shows that the convective Urca neutrinos reduce the rate of increase of entropy that would otherwise be associated with the input of nuclear energy and slow down the convective current, but, unlike the "thermal" Urca process, they do not reduce the entropy or temperature.
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