论文标题
变体尼尔森 - 巴尔机制，侵犯最小的风味
Variant Nelson-Barr Mechanism with Minimal Flavor Violation
论文作者
论文摘要
在使用自发CP违规解决强大的CP问题的一般框架内，我们构建了一个变异的Nelson-Barr模型，其中标准模型（SM）Quark对强CP阶段的贡献被新的重型QCD收费的费米子取消。通过在SM夸克的相同全球风味对称性下为新的有色状态选择共轭表示来确保这种取消。我们选择全球风味对称性是最小的风味，我们抑制了强大的CP阶段的高阶校正，以远低于当前的实验限制。自发的对称性破裂源自自发的八十多个无质量的金石玻色子，在对称性破裂量表上产生了强大的天体物理约束。在早期的宇宙中，可以通过可测量的水平从与重彩费的相互作用中进行热产生金石玻色子。作为加热温度的函数，预测的$Δn_ {\ rm eff} $显示了一个有趣的平台行为，我们将“风味阶梯”配音为``风味楼梯''，该行为编码有关SM Quark风味结构的信息。
Within the general framework of using spontaneous CP violation to solve the strong CP problem, we construct a variant Nelson-Barr model in which the Standard Model (SM) quark contribution to the strong CP phase is cancelled by new heavy QCD-charged fermions. This cancellation is ensured by choosing conjugate representations for the new colored states under the same global flavor symmetry of SM quarks. Choosing the global flavor symmetry to be that of minimal flavor violation, we suppress higher-order corrections to the strong CP phase to well below current experimental constraints. More than two dozen massless Goldstone bosons emerge from spontaneous flavor symmetry breaking, which yield strong astrophysical constraints on the symmetry breaking scale. In the early universe, the Goldstone bosons can be thermally produced from their interactions with the heavy colored fermions and contribute to $ΔN_{\rm eff}$ at a measurable level. As a function of reheating temperature, the predicted $ΔN_{\rm eff}$ shows an interesting plateau behavior we dub the ``flavor stairway", which encodes information about the SM quark flavor structure.
