在SM上精确测量230 GeV和250 GeV的Higgs反冲质量和Ecm截面

用$Z$的强子衰变模在未来$e^{+}e^{-}$对撞机上测量$σ_{Zh}$的总截面

A measurement of the total cross section of $σ_{Zh}$ at a future $e^{+}e^{-}$ collider using the hadronic decay mode of $Z$

本文研究了在未来的$e^+e^-$对撞机上利用$Z$的强子衰变模测量Higgs-strahlung过程$(σ_{Zh})$的总截面的可行性。为了测量$Z$强子衰变产生的反冲质量，利用ILC束流参数，对$\sqrt{s}=350$和500 GeV的ILD全探测器模拟产生的样品进行了简单的切割分析。在$350$ GeV，反冲质量分布中的一个凸起被重建，并且假设165 fb $^{-1}$数据和$e^-(e^+)$束偏振分别为-80%（+30%）和+80%（-30%），获得$Δσ_{Zh}/σ_{Zh}$ = 3.4%。在$500$ GeV，在反冲质量分布中没有看到明显的希格斯玻色子峰，然而，从事件的过量，假设500 fb $^{-1}$数据，$e^-(e^+)$束偏振为-80%（+30%），获得$Δσ_{Zh}/σ_{Zh}=3.9%$。

Model-Independent Measurement of the e+e- -> HZ Cross Section at a Future e+e- Linear Collider using Hadronic Z Decays

A future e+e- collider, such as the ILC or CLIC, would allow the Higgs sector to be probed with a precision significantly beyond that achievable at the High-Luminosity LHC. A central part of the Higgs programme at an e+e- collider is the model-independent determination of the absolute Higgs couplings to fermions and to gauge bosons. Here the measurement of the e+e-->HZ Higgsstrahlung cross section, using the recoil mass technique, sets the absolute scale for all Higgs coupling measurements. Previous studies have considered e+e- ->ZH with Z->l+l-, where l = electron or muon. In this paper it is…

Prospects for direct searches for light Higgs bosons at the ILC with 250 GeV

The particle discovered in the Higgs boson searches at the LHC with a mass of about 125 GeV is compatible within the present uncertainties with the Higgs boson predicted in the Standard Model (SM), but it could also be identified with one of the neutral Higgs bosons in a variety of Beyond the SM (BSM) theories with an extended Higgs sector. The possibility that an additional Higgs boson (or even more than one) could be lighter than the state that has been detected at 125 GeV occurs generically in many BSM models and has some support from slight excesses that were observed above the background …

Measurement of the Higgs boson mass and $e^+e^- \to ZH$ cross section using $Z \to μ^+μ^-$ and $Z \to e^+ e^-$ at the ILC

This paper presents a full simulation study of the measurement of the production cross section ($σ_{\mathrm{ZH}}$) of the Higgsstrahlung process $\mathrm{e^{+}e^{-}\rightarrow ZH}$ and the Higgs boson mass ($M_{\mathrm{H}}$) at the International Linear Collider (ILC), using events in which a Higgs boson recoils against a Z boson decaying into a pair of muons or electrons. The analysis is carried out for three center-of-mass energies $\sqrt{s}$ = 250, 350, and 500 GeV, and two beam polarizations $\mathrm{e_{L}^{-}e_{R}^{+}}$ and $\mathrm{e_{R}^{-}e_{L}^{+}}$, for which the polarizations of $\ma…

Inclusive Higgsstrahlung cross section measurements with the new reference sample method

An accurate determination of the Higgsstrahlung cross section is one of the main objectives at a future electron-positron collider. It allows for the only Higgs boson decay model independent measurement of the total Higgs width. Current results use the recoil mass shape method. That technique can be applied to Higgsstrahlung events with Z boson decays into muons, into electrons and, with reservations, into quarks. The samples built from Higgsstrahlung events with Z boson decays into taus and neutrinos are not used in previous analyses. We present here a new method, the reference sample method.…

在直线对撞机上实现精确希格斯粒子物理的前景

Prospects for Precision Higgs Physics at Linear Colliders

线性电子对撞机为精确测量希格斯玻色子的性质提供了极好的可能性。在接近Z-希格斯阈值的能量下，希格斯玻色子可以在Z玻色子的反冲中进行研究，不仅可以获得精确的质量测量，还可以直接测量大多数衰变模式的分支比，包括可能衰变为不可见的物质。在更高的能量下，希格斯玻色子玻色子与顶夸克的耦合和希格斯玻色子玻色子的自耦合也可以被测量。在接近1 TeV及以上的能量下，WW聚变中希格斯粒子产生的上升截面允许测量非常小的分支比，包括μ子对的分支比。这些实验使我们有可能以一种与模型无关的方式来确定希格斯玻色子玻色子的完整轮廓。根据CLIC概念设计报告和ILC技术设计报告框架内进行的详细模拟研究的结果，总结了这些测量的前景。