"Xsec limits, TChiHH-G" of "Search for higgsinos decaying to two Higgs bosons and missing transverse momentum in proton-proton collisions at $\sqrt{s}$ = 13 TeV"

Results are presented from a search for physics beyond the standard model in proton-proton collisions at $\sqrt{s}=13$ TeV in channels with two Higgs bosons, each decaying via the process H$\to b\overline{b}$, and large missing transverse momentum. The search uses a data sample corresponding to an integrated luminosity of 137 fb$^{-1}$ collected by the CMS experiment at the CERN LHC. The search is motivated by models of supersymmetry that predict the production of neutralinos, the neutral partners of the electroweak gauge and Higgs bosons. The observed event yields in the signal regions are found to be consistent with the standard model background expectations. The results are interpreted using simplified models of supersymmetry. For the electroweak production of nearly degenerate higgsinos, each of whose decay chains yields a neutralino ($\widetilde{\chi}^0_1$) that in turn decays to a massless goldstino and a Higgs boson, $\widetilde{\chi}^0_1$ masses in the range 175 to 1025 GeV are excluded at 95\% confidence level. For the strong production of gluino pairs decaying via a slightly lighter $\widetilde{\chi}^0_2$ to H and a light $\widetilde{\chi}^0_1$, gluino masses below 2330 GeV are excluded.本研究报道了在大型强子对撞机（Large Hadron Collider, LHC）的紧凑型缪子线圈（Compact Muon Solenoid, CMS）实验采集的、积分亮度为137 fb⁻¹的质子-质子碰撞数据中，搜寻超出标准模型（Standard Model, SM）物理的结果。该搜寻针对质心系能量sqrt{s}=13 TeV下的双希格斯玻色子衰变道，每个希格斯玻色子均通过 ext{H} o boverline{b}过程衰变，并伴随大横向缺失动量。本次搜寻的理论动机来自超对称（supersymmetry）模型，该类模型预言了中性微子（neutralino）的产生——中性微子是电弱规范玻色子与希格斯玻色子的中性伴子。信号区域内观测到的事例产额与标准模型本底预期相符。本结果基于超对称简化模型进行诠释：针对衰变链均产生中性微子widetilde{chi}^0_1、且该中性子进一步衰变为无质量戈德斯蒂诺（goldstino）与希格斯玻色子的近简并希格斯微子（higgsino）电弱产生过程，175 GeV至1025 GeV区间内的widetilde{chi}^0_1质量在95%置信度下被排除；针对通过质量略轻的widetilde{chi}^0_2衰变至希格斯玻色子与轻中性微子widetilde{chi}^0_1的胶微子（gluino）对强产生过程，2330 GeV以下的胶微子质量被排除。