论文标题
希格斯门户网站到暗物质，$ b \ to k^{（*）} $衰减
Higgs portal to dark matter and $B\to K^{(*)}$ decays
论文作者
论文摘要
我们考虑了一个Higgs门户模型，其中125-GEV Higgs Boson与轻单元介质$ H_2 $耦合到黑暗部门的颗粒，并研究Belle II实验中的S H_2 $衰变的潜在$ B \。将依赖于量规的外壳标准模型$ b $ - $ s $ -s -higgs顶点与希格斯混合角的正弦相乘，没有给出正确的$ b $ -s $ -s $ -s $ -s $ h_2 $ h_2 $ tertex。我们通过计算$ b $ - $ s $ - $ h_2 $ h_2 $ h_2 $r_ξ$量表来阐明此问题，并演示$ξ$依赖关系如何从涉及shell或Off-shell $ h_2 $的物理衰减率中取消物理衰减率。然后，我们将$ b \重新审视到s H_2 $现象学，并指出同时研究$ b \ to k^* h_2 $和$ b \ to K H_2 $有助于区分Higgs门户网站和黑暗部门的替代模型。我们进一步倡导使用$ H_2 $的寿命信息，其中包含在流离失所的vertex数据中，$ h_2 $衰减回到标准模型粒子，以更好地限制$ H_2 $质量或揭示额外的$ H_2 $衰减模式到长期寿命的粒子中。
We consider a Higgs portal model in which the 125-GeV Higgs boson mixes with a light singlet mediator $h_2$ coupling to particles of a Dark Sector and study potential $b\to s h_2$ decays in the Belle II experiment. Multiplying the gauge-dependent off-shell Standard-Model $b$-$s$-Higgs vertex with the sine of the Higgs mixing angle does not give the correct $b$-$s$-$h_2$ vertex. We clarify this issue by calculating the $b$-$s$-$h_2$ vertex in an arbitrary $R_ξ$ gauge and demonstrate how the $ξ$ dependence cancels from physical decay rates involving an on-shell or off-shell $h_2$. Then we revisit the $b\to s h_2$ phenomenology and point out that a simultaneous study of $B\to K^* h_2$ and $B\to K h_2$ helps to discriminate between the Higgs portal and alternative models of the Dark Sector. We further advocate for the use of the $h_2$ lifetime information contained in displaced-vertex data with $h_2$ decaying back to Standard-Model particles to better constrain the $h_2$ mass or to reveal additional $h_2$ decay modes into long-lived particles.
