标题： 不稳定的重马约拉纳中微子与轻子生成 显示英文标题

标题： Unstable Heavy Majorana Neutrinos and Leptogenesis

摘要： 我们提出一种新机制，产生非零的轻子数不对称性，该机制基于重马约拉纳中微子的衰变。 如果它们在非平衡状态下产生，如在再加热情景中发生的情况，并且是快速衰变的质量本征态的叠加，那么当质量差$\Delta m$相对于宽度$\Gamma$很小时，它们的衰变率包含干涉项。 产生的轻子不对称性，是$B^0-\bar{B}^0$系统中时间积分CP不对称性的类比，被发现与$\Delta m/\Gamma$成正比。 显示英文摘要

摘要： We propose a new mechanism producing a non-vanishing lepton number asymmetry, based on decays of heavy Majorana neutrinos. If they are produced out of equilibrium, as occurs in preheating scenario, and are superpositions of mass eigenstates rapidly decaying, their decay rates contains interference terms provided the mass differences $\Delta m$ are small compared to widths $\Gamma$. The resulting lepton asymmetry, which is the analogue of the time-integrated CP asymmetry in $B^0-\bar{B}^0$ system, is found to be proportional to $\Delta m/\Gamma$.