Talk at Second Workshop on Theory, Phenomenology and Experiments in Heavy Flavour Physics, June 16-18 2008, Anacapri, Italy. 6 pages, 4 figures. Remark on D energy, 3 figures and Eqs. (7),(10) corrected. 3 references added
在最小超对称标准模型中，当参数tan β很大时，B物理对希格斯玻色子的影响很敏感。我简要地总结了B -> mu+ mu-和B -> tau nu在寻找新的希格斯效应中的作用，并提出了关于衰变B -> D tau nu的新结果：利用形状因子的解析性质，人们可以预测比率R=Br（B-> D tau nu）/Br（B -> D l nu），l=e，mu，具有小的强子不确定性。在标准模型中，如果使用重风味平均组的矢量形状因子，则发现R= 0.31 +/- 0.02，Br（B^- -> D^0 tau^-抗-nu）=（0.71 +/- 0.09）%和Br（抗-B ^0 -> D^+ tau^-抗-nu）=（0.66 +/- 0.08）%。B -> D τ nu与B -> τ nu在寻找带电希格斯玻色子玻色子效应方面具有竞争力。对后者特别敏感的是衰变链anti-B -> D anti-nu tau^-[-> pi-nu]中的微分分布。
英文摘要：
B physics is sensitive to the effects of Higgs bosons in the Minimal Supersymmetric Standard Model, if the parameter tan beta is large. I briefly summarise the role of B -> mu+ mu- and B -> tau nu in the hunt for new Higgs effects and present new results on the decay B -> D tau nu: Using the analyticity properties of form factors one can predict the ratio R=Br(B -> D tau nu)/Br(B -> D l nu), l=e,mu, with small hadronic uncertainties. In the Standard Model one finds R= 0.31 +/- 0.02, Br(B^- -> D^0 tau^- anti-nu) = (0.71 +/- 0.09)% and Br(anti-B^0 -> D^+ tau^- anti-nu)= (0.66 +/- 0.08)%, if the vector form factor of the Heavy Flavor Averaging Group is used. B -> D tau nu is competitive with B -> tau nu in the search for effects of charged Higgs bosons. Especially sensitive to the latter is the differential distribution in the decay chain anti-B -> D anti-nu tau^-[->pi- nu].
We show the reinterpretation of existing searches for exotic decays of the Standard Model (SM)-like Higgs, $H \to aa (hh)$, in various final states, in the framework of the 2-Higgs Doublet Model (2HDM) Type-I. We then explore a new search for such light Higgses, $a$ and $h$, at the Large Hadron Collider (LHC) Run 3 for an integrated luminosity of 300 $\text{fb}^{-1}$. After performing a scan over the model parameters, we found that the inverted scenario of Type-I offers a new promising signal in the form of the following cascade decays: $H \to Z^{*}a \to Z^{*}Z^{*}h \to b\overline{b} μ^- μ^+ j…
The assumption that strongly interacting sparticles will decay directly to the LSP plus jets breaks down in situations where those decays are Yukawa suppressed. That occurs when producing the first two generations of squarks and when, at the same time, there are several electroweakinos lighter than those squarks. In this paper we analyze the signal of pair production of squarks that subsequently decay to an intermediate neutralino ($\tildeχ_3^0$) plus jets. The neutralino will then decay to the LSP (mainly higgsino) and a Higgs. We have simulated the events and designed a discovery strategy ba…
Beyond the Standard Model Higgs physics: Hunting $h \rightarrow bs$ with Higgs-strahlung at CEPC and FCC-ee
Benemérita Universidad Autónoma de Puebla（普埃布拉自治大学）；Centro Interdisciplinario de Investigación y Enseñanza de la Ciencia (CIIEC)（科学交叉研究与教育中心）；Universidad Nacional Autónoma de México（墨西哥国立自治大学）
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Hunting physics beyond the standard model with unusual $W^\pm$ and $Z$ decays
在扩展的超对称模型的框架内，$W^\pm$和$Z$玻色子的非标准壳层衰变是可能的，即，与最小超对称标准模型相比，具有单重态和/或新的耦合。这些模式通常出现在参数空间中具有轻单态标量、伪标量和中性伴子的区域。在这封信中，我们强调这些状态如何导致新的信号在对撞机从$Z$ -或$W^\pm$ -玻色子衰变与提示或位移的多轻子/τ喷流/喷流/光子在最终状态。这些新的模式将提供新物理学的明显证据，即使直接搜索仍然不成功。我们讨论了探测这些新的信号使用现有的大型强子对撞机运行I数据集的可能性。我们也解决了同样的情况下，大型强子对撞机运行-II，以及为未来的对撞机。我们用“$μ$ from $ν$“超对称标准模型来解释我们的观测，其中三代右手中微子超场被用来解决最小超对称标准模型的缺点。我们还扩展了我们的讨论的其他变种的超对称模型，可以容纳类似的签名。
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Motivated by the search for flavor-changing neutral current (FCNC) top quark decays at the LHC, we calculate rare Higgs three body decay $H\rightarrow Wbc$ induced by top-Higgs FCNC coupling in the littlest Higgs model with T-parity(LHT). We find that the branching ratios of $H\rightarrow Wbc$ in the LHT model can reach $\mathcal O(10^{-7})$ in the allowed parameter space.
