论文标题
重力诱导发生的风味效应
Flavour effects in gravitational leptogenesis
论文作者
论文摘要
在I型Seesaw机制中，重力背景中右手（RH）中微子的量子作用导致Lepton和Anti-Leptons的不对称传播，从而使RICCI标量和中微子dirac-ukawa偶联化学潜力依赖于依赖性的化学潜力，因此在平衡中具有Lepton的不对称性。在高温下，违反散射过程的Lepton数量试图在平衡中保持动态产生的Lepton不对称性。但是，当温度下降时，相互作用变得较弱，不对称冻结。冻结的不对称性可以在标准的福基塔 - 亚纳吉达瘦植物发生阶段（$ t_i \ sim m_i $，其中$ m_i $是$ i $ i $ i $ th rh neutrino）之前充当现有的不对称性。因此，自然要考虑给定的RH质量谱的引力诱导生成的生存能力，这与衰减中成功的瘦素发生不一致。对这种重力引起的Lepton不对称的主要威胁能够成功地重现观察到的Baryon与Photon比率，这是Lepton数字违反了$ T_I \ SIM M_I $的冲洗过程。在用两个RH中微子建立的最小seesaw中，这些冲洗过程足以消除显着幅度的预先存在的不对称性。我们表明，当考虑风味对冲洗过程的影响时，该机制为质量谱$ M_2 \ gg 10^9 {\ rm GEV} \ gg m_1 $提供成功的瘦素发生（重力）的可能性，并使用$ m_1 \ gtrsim 6.3 \ gtrsim 6.3 \ times 10^6 $ gev。然后，我们简要讨论该机制如何在低能CP阶段和绝对光中微子质量尺度上留下其烙印。
Within the Type-I seesaw mechanism, quantum effects of the right-handed (RH) neutrinos in the gravitational background lead to an asymmetric propagation of lepton and anti-leptons which allows a Ricci scalar and neutrino Dirac-Yukawa coupling dependent chemical potential and therefore a lepton asymmetry in equilibrium. At high temperature, lepton number violating scattering processes try to maintain a dynamically generated lepton asymmetry in equilibrium. However, when the temperature drops down, the interactions become weaker, and the asymmetry freezes out. The frozen out asymmetry can act as a pre-existing asymmetry prior to the standard Fukugita-Yanagida leptogenesis phase ($T_i\sim M_i$, where $M_i$ is the mass of $i$th RH neutrino). It is then natural to consider the viability of gravitational leptogenesis for a given RH mass spectrum which is not consistent with successful leptogenesis from decays. Primary threat to this gravity-induced lepton asymmetry to be able to successfully reproduce the observed baryon-to-photon ratio is the lepton number violating washout processes at $T_i\sim M_i$. In a minimal seesaw set up with two RH neutrinos, these washout processes are strong enough to erase a pre-existing asymmetry of significant magnitude. We show that when effects of flavour on the washout processes are taken into account, the mechanism opens up the possibility of successful leptogenesis (gravitational) for a mass spectrum $M_2\gg 10^9 {\rm GeV}\gg M_1$ with $M_1 \gtrsim 6.3 \times 10^6$ GeV. We then briefly discuss how, in general, the mechanism leaves its imprints on the low energy CP phases and absolute light neutrino mass scale.
