标题： 电子-正电子俘获率和与核子的电子-正电子等离子体的稳态平衡条件 显示英文标题

标题： Electron Positron Capture Rates and the Steady State Equilibrium Condition for Electron-Positron Plasma with Nucleons

摘要： 推导了任意退化度下所有粒子的β过程反应率，并找到了一个稳态平衡条件 {\it 分析的}，如果物质对中微子是透明的，在热电子 - 正电子等离子体与核子中电子和正电子俘获率相等时，该条件由 $\mu_n=\mu_p+2\mu_e$ 给出。 这个简单的解析公式仅在电子是非简并或弱简并时有效，这在热电子 - 正电子等离子体中通常是满足的。 因此，它可以用来有效地确定富含正电子的热物质的稳态。 基于这个解析条件，已知重子数密度和温度的情况下，如果核子是非简并的，则只需一个代数方程来确定电子分数，这显示了解析平衡条件的巨大优势。 显示英文摘要

摘要： The reaction rates of the beta processes for all particles at arbitrary degeneracy are derived, and an {\it analytic} steady state equilibrium condition $\mu_n=\mu_p+2\mu_e$ which results from the equality of electron and positron capture rates in the hot electron-positron plasma with nucleons is also found, if the matter is transparent to neutrinos. This simple analytic formula is valid only if electrons are nondegenerate or mildly degenerate, which is generally satisfied in the hot electron-positron plasma. Therefore, it can be used to efficiently determine the steady state of the hot matter with plenty of positrons. Based on this analytic condition, given the baryon number density and the temperature, if the nucleons are nondegenerate, only one algebraic equation for determining the electron fraction is obtained, which shows the great advantage of the analytic equilibrium condition.