论文标题
暗物质$ z^\ prime $和xenon1t超过$ u（1）_x $扩展标准模型
Dark Matter $Z^\prime$ and XENON1T Excess from $U(1)_X$ Extended Standard Model
论文作者
论文摘要
A gauged $U(1)_X$ symmetry appended to the Standard Model (SM) is particularly well-motivated since it can account for the light neutrino masses by the seesaw mechanism, explain the origin of baryon asymmetry of the universe via leptogenesis, and help implement successful cosmological inflation with the $U(1)_X$ breaking Higgs field as the inflaton.在此框架中，我们提出了一个轻暗物质（DM）方案，其中$ u（1）_x $ gauge boson $ z^\ prime $表现为宇宙中的DM粒子。我们讨论了几个keV的$ z^\ prime $质量和$ u（1）_x $量表耦合$ g_x \ simeq 10^{ - 16} $如何很好地适合XENON1T协作最近报道的电子逆流能源中的多余的情况。为了在存在这样的微小耦合的情况下重现观察到的DM遗物密度，我们提出将模型扩展到两个组分的DM场景。 $ z^\ prime $ dm密度可以通过将$ z^\ prime $ boson耦合到伙伴higgs-portal标量DM与大$ u（1）_x $ charding通过$ z^\ prime $ boson与观察到的DM密度相媲美。
A gauged $U(1)_X$ symmetry appended to the Standard Model (SM) is particularly well-motivated since it can account for the light neutrino masses by the seesaw mechanism, explain the origin of baryon asymmetry of the universe via leptogenesis, and help implement successful cosmological inflation with the $U(1)_X$ breaking Higgs field as the inflaton. In this framework, we propose a light dark matter (DM) scenario in which the $U(1)_X$ gauge boson $Z^\prime$ behaves as a DM particle in the universe. We discuss how this scenario with $Z^\prime$ mass of a few keV and a $U(1)_X$ gauge coupling $g_X \simeq 10^{-16}$ can nicely fit the excess in the electronic recoil energy spectrum recently reported by the XENON1T collaboration. In order to reproduce the observed DM relic density in the presence of such a tiny gauge coupling, we propose an extension of the model to a two-component DM scenario. The $Z^\prime$ DM density can be comparable to the observed DM density by the freeze-in mechanism through the coupling of $Z^\prime$ boson to a partner Higgs-portal scalar DM with a large $U(1)_X$ charge.
