标题： 重夸克辐射 显示英文标题

标题： Radiation of Heavy Quarks

摘要： 产生由一对无质量费米子辐射出的重费米子的速率被解析地计算出来。 结合相应的虚贡献的解析计算，可以得到由无质量费米子辐射出的一对重费米子所引起的截面的阶$\alpha^2$修正。 推导出适用于大质量和小质量的近似，并显示与以前的计算一致。 显示英文摘要

摘要： The rate for the production of massive fermions radiated off a pair of massless fermions is calculated analytically. Combined with the analytic calculation of the corresponding virtual contribution one obtains the order $\alpha^2$ correction to the cross section which is induced by the real and virtual radiation of a pair of massive fermions by massless fermions. Approximations valid for large and for small masses are derived and shown to agree with earlier calculations.