Farzan Y, Valle J W F
Institute for Studies in Theoretical Physics and Mathematics (IPM), Post Office Box 19395-5531, Tehran, Iran.
Phys Rev Lett. 2006 Jan 13;96(1):011601. doi: 10.1103/PhysRevLett.96.011601. Epub 2006 Jan 4.
Successful leptogenesis within the simplest type I supersymmetric seesaw mechanism requires the lightest of the three right-handed neutrino supermultiplets to be heavier than approximately 10(9) GeV. Thermal production of such (s)neutrinos requires very high reheating temperatures which result in an overproduction of gravitinos with catastrophic consequences for the evolution of the Universe. In this Letter, we let R parity be violated through a lambda(i)N(i)H(u)H(d) term in the superpotential, where N(i) are right-handed neutrino supermultiplets. We show that in the presence of this term, the produced lepton-antilepton asymmetry can be enhanced. As a result, even for N1 masses as low as 10(6) GeV or less, we can obtain the observed baryon asymmetry of the Universe without gravitino overproduction.
在最简单的I型超对称跷跷板机制中成功实现轻子生成，要求三个右手型中微子超多重态中最轻的那个重于约10⁹ GeV。这种（s）中微子的热产生需要非常高的再加热温度，这会导致引力子的过量产生，对宇宙演化产生灾难性后果。在本快报中，我们通过超势中的λᵢNᵢHᵤHd项使R宇称破缺，其中Nᵢ是右手型中微子超多重态。我们表明，在该项存在的情况下，产生的轻子 - 反轻子不对称性可以增强。结果，即使对于低至10⁶ GeV或更低的N1质量，我们也可以在不产生过量引力子的情况下获得观测到的宇宙重子不对称性。
