arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2303.11252hep-ph
收藏

通过顶夸克-粲夸克混合实现电弱重子生成

Electroweak baryogenesis via top-charm mixing

Shinya Kanemura, Yushi Mura

备注：
26 pages, 4 figures, references and some explanation added
阅读 PDF
arXiv 页面 ↗HTML 原文 ↗

AI总结：

本文研究了双Higgs二重态模型中通过顶夸克-粲夸克混合实现电弱重子生成的机制，发现非对角元素的绝对值能增强Higgs势中的CP破坏相位，从而生成足够的重子数解释宇宙重子不对称性，并可通过K介子稀有衰变等实验进行测试。

摘要：

我们研究了具有夸克味道混合的双Higgs二重态模型中电弱重子生成的情景。通常，夸克与额外Higgs玻色子的Yukawa相互作用非对角分量受到味道改变中性流数据的严格限制。然而，顶夸克-粲夸克混合并非如此，因此可以取较大的非对角元素，这有助于生成宇宙重子不对称性。结果表明，Boltzmann方程源项中非对角元素的CP破坏相位通过重新定相被消除。这一结果与之前关于由味道非对角Yukawa耦合引起的电弱重子生成的研究略有不同。相反，我们发现顶夸克-粲夸克非对角元素的绝对值增强了Higgs势中的CP破坏相位，由此可生成足够的重子数来解释观测到的宇宙重子不对称性。我们发现该情景在当前实验数据下是可行的。该模型可通过当前和未来的各种味道实验测量（如K介子稀有衰变）、高能对撞机实验以及引力波观测进行测试。我们模型的特征预测是K介子稀有衰变中的偏差。$K^+ \to π^+ ν\overlineν$和$K_L \to π^0 ν\overlineν$的分支比可分别偏离约10%和1%的量级，这可能在未来的K介子实验（如NA62和KOTO step-2）中得到测试。

英文摘要：

We investigate a scenario of electroweak baryogenesis in the two Higgs doublet model with quark flavor mixing. In general, off-diagonal components of quark Yukawa interactions with additional Higgs bosons are strongly constrained by the data for flavor changing neutral currents. However, top-charm quark mixing is not the case, so that a large off-diagonal element can be taken, which can contribute to generating baryon asymmetry of the universe. It turns out that CP violating phases of the off-diagonal element in the source term in the Boltzmann equation are eliminated by the rephasing. This result is somewhat different from previous works on electroweak baryogenesis by flavor off-diagonal Yukawa couplings. Instead, we find that the absolute value of the top-charm off-diagonal element enhances CP violating phases in the Higgs potential, by which sufficient amount of the baryon number can be generated to explain the observed baryon asymmetry of the universe. We find that such a scenario is viable under the current experimental data. The model can be tested by the current and future measurements of various flavor experiments like Kaon rare decays, in addition to high energy collider experiments as well as gravitational wave observations. Characteristic predictions of our model would be deviations in Kaon rare decays. Branching ratios of $K^+ \to π^+ ν\overlineν$ and $K_L \to π^0 ν\overlineν$ can deviate by the order of 10% and 1%, respectively, which may be tested at future Kaon experiments such as NA62 and KOTO step-2.

机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。

↑