标题： 轴子暗物质的费米子耦合 显示英文标题

标题： On the fermionic couplings of axionic dark matter

摘要： 在非相对论极限下，人们认为暗物质轴子与费米子的两种相互作用占主导地位：一种是由轴子场的空间梯度引起的，称为轴子风；另一种是由轴子场的时间导数引起，产生轴子电离效应。 通过推广施密特定理，证明了后一种算符实际上被强烈屏蔽。 对于中性费米子，它可以完全旋转掉且无法观测到。 对于带电费米子，唯一能够透过屏蔽效应显现出来的效应是一种由轴子诱导的电偶极矩（EDM）。 这些EDM与轴子与胶子的耦合无关，代表了类似于狄拉克理论中g=2磁矩的预测，不受原始施密特定理的进一步屏蔽，并最终导致通常的轴子电离效应。 这两个主要的物理现象后果是：首先，由轴子诱导的中子EDM可能比从轴子胶子耦合预期的大几个数量级；其次，电子EDM也可能变得可用，并且实际上对遗迹轴子非常敏感。 显示英文摘要

摘要： In the non-relativistic limit, two types of dark matter axion interactions with fermions are thought to dominate: one is induced by the spatial gradient of the axion field and called the axion wind, and the other by the time-derivative of the axion field, generating axioelectric effects. By generalizing Schiff theorem, it is demonstrated that this latter operator is actually strongly screened. For a neutral fermion, it can be entirely rotated away and is unobservable. For charged fermions, the only effect that can peek through the screening is an axion-induced electric dipole moment (EDM). These EDMs are not related to the axion coupling to gluons, represent a prediction of the Dirac theory analogous to the g = 2 magnetic moments, are not further screened by the original Schiff theorem, and are ultimately responsible for inducing the usual axioelectric ionization. The two main phenomenological consequences are then that first the axion-induced neutron EDM could be several orders of magnitude larger than expected from the axion gluonic coupling, and second, that the electron EDM could also become available, and could actually be highly sensitive to relic axions.