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$$
p_{{\mathrm  {total}}}={\biggl (}{\frac  {\mu _{e}m_{p}}{{\bar  {\mu }}m_{u}}}{\biggr )}8\chi ^{3}{\frac  {T}{T_{e}}}+F(\chi )+{\frac  {8\pi ^{4}}{15}}{\biggl (}{\frac  {T}{T_{e}}}{\biggr )}^{4}
$$
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