arXiv 2003.110432020-03-27hep-phhep-ex

从胶子聚变中解开非共振希格斯玻色子玻色子对产生的新物理效应

Disentangling new physics effects on non-resonant Higgs boson pair production from gluon fusion

Kingman Cheung, Adil Jueid, Chih-Ting Lu, Jeonghyeon Song, Yeo Woong Yoon

备注：: References are added: 29 pages with 8 figures
发表信息：: Phys. Rev. D 103, 015019 (2021)
DOI：: 10.1103/PhysRevD.103.015019

摘要：

胶子聚变对非共振di-Higgs过程产生的新物理效应有两种：非SM Higgs三线性自耦合$λ_{hhh}$和新的有色粒子在环中运行。为了理清不同的新物理贡献，我们研究了它们在运动学分布上的特征。假设观测到的总截面大约是SM期望值的三倍，我们考虑了$λ_{hhh}/λ_{hhh}^{\rm SM} =-0.5, 5.5$的情况以及一个新的物理模型，在一个II型双希格斯模型，称为VLQ-2 HDM中的重矢量夸克。一个合理的基准点建议在确切的错误符号的限制，向上型VLQ和向下型VLQ之间的相反符号的耦合到希格斯玻色子的胶子融合的单希格斯生产的贡献，导致取消。由于环路中重VLQ的阈值效应，VLQ-2 HDM适应了希格斯玻色子对不变质量（$M_{hh}$）和希格斯玻色子横动量（$p_T^h$）分布中的颠簸。两个凸起的位置密切相关，分别为$ M_{hh} \simeq 2 M_{\rm VLQ}$和$p_T^h \simeq M_{\rm VLQ}$。此外，位于重VLQ质量处的凸起自然地将$M_{hh}$和$p_T^h$分布提升到高质量和高$p_T^h$区域。另一方面，非SM Higgs三线性耦合的情况下，分布移动到低$ M_{hh}$和$p_T^h$区。因此，具有高$M_{hh}$和高$p_T^h$的运动区域将是VLQ-2 HDM的确凿信号。还对di-Higgs信号进行了完整的HL-LHC模拟，证实了$b \bar{b} b \bar{b}$终态可以区分VLQ-2 HDM。

英文摘要：

There are two kinds of new physics effects on non-resonant di-Higgs process from gluon fusion, non-SM Higgs trilinear self-coupling $λ_{hhh}$ or new colored particles running in the loop. With the aim of disentangling different new physics contributions, we study their characteristics in the kinematic distributions. Assuming that the total cross section is observed to be about three times as large as the SM expectation, we consider the cases of $λ_{hhh}/λ_{hhh}^{\rm SM} =-0.5, 5.5$ as well as a new physics model with heavy vectorlike quarks in a type-II two Higgs double model, called the VLQ-2HDM. A reasonable benchmark point is suggested in the exact wrong-sign limit, where the opposite sign between the up-type VLQ and down-type VLQ couplings to the Higgs boson causes the cancellation of their contributions to the single-Higgs production from gluon fusion. Because of the threshold effects from the heavy VLQs in the loop, the VLQ-2HDM accommodates the bumps in the distributions of the invariant mass of the Higgs boson pair ($M_{hh}$) and the transverse momentum of a Higgs boson ($p_T^h$). The positions of two bumps are closely related as $ M_{hh} \simeq 2 M_{\rm VLQ}$ and $p_T^h \simeq M_{\rm VLQ}$. In addition, the bumps located at the heavy VLQ mass naturally lift up the $M_{hh}$ and $p_T^h$ distributions into high-mass and high-$p_T^h$ regions. On the other hand, the non-SM Higgs trilinear coupling cases have the distributions shift into low $ M_{hh}$ and $p_T^h$ regions. Therefore, the kinematic region with high $M_{hh}$ and high $p_T^h$ will be a smoking-gun signal for the VLQ-2HDM. Full HL-LHC simulations for the di-Higgs signals are also performed, confirming that the $b \bar{b} b \bar{b}$ final state can distinguish the VLQ-2HDM.

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。

摘要：

英文摘要：

相关论文