Higgs Recoil Mass and Higgs-Strahlung Cross-Section Study for the ILD LOI

550 GeV线性对撞机上Higgs自耦合测量

Higgs Self-Coupling Measurement at a Linear Collider at 550 GeV

本文研究550 GeV线性对撞机上Higgs自耦合测量，通过双Higgs生产探测三线性Higgs自耦合，结合ILD探测器模拟分析与快速SGV模拟，提升味标签和动量重建精度。

Evaluation of measurement accuracy of $h \to τ^+ τ^-$ branching ratio at the ILC with $\sqrt{s} = 250$ GeV and 500 GeV

We evaluate the measurement accuracy of the branching ratio of $h \to τ^+ τ^-$ at $\sqrt{s} = 250$ GeV and 500 GeV at the ILC with the ILD detector simulation. For the $\sqrt{s} = 250$ GeV, we assume the Higgs mass of $M_h = 120$ GeV, branching ratio of $\mathrm{Br}(h \to τ^+ τ^-) = 8.0 \ %$, beam polarization of $P(e^-, e^+) = (-0.8, +0.3)$, and integrated luminosity of $\int L \ dt = 250 \ \mathrm{fb ^{-1}}$. The Higgs-strahlung process $e^+ e^- \to Zh$ with $Z \to e^+ e^-$, $Z \to μ^+ μ^-$, $Z \to q\bar{q}$ mode are analyzed. The measurement accuracy is calculated to be $Δ(σ\cdot \mathrm{Br…

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

A feasibility to use the hadronic decay mode of $Z$ for the model independant measurement of the total cross section of Higgs-strahlung process $(σ_{Zh})$ at a future $e^+e^-$ collider was studied. For the recoil mass measurement from hadronic decay of $Z$, a simple cut based analysis was applied on samples produced by the ILD full detector simulation at $\sqrt{s}=350$ GeV and 500 GeV using the ILC beam parameters. At $350$ GeV, a bump in the recoil mass distribution was reconstructed, and $Δσ_{Zh}/σ_{Zh}$ = 3.4% was obtained assuming 165 fb$^{-1}$ data with $e^-(e^+)$ beam polarization of -80…

在反物质对撞机Higgs工厂中寻找轻量奇特标量粒子的衰变

Searches for light exotic scalar decays at the e$^+$e$^-$ Higgs factory

本文研究了在Higgs工厂中通过标量辐射过程寻找轻量奇特标量粒子的实验方法，基于ILD模拟和Delphes框架预测了不同衰变通道的灵敏度和横截面限制。

Feasibility of a minimum bias analysis of $e^+e^-\to ZH \to q\bar{q}+X$ at a 250 GeV ILC

The precision measurements of the Higgs properties is crucial for a better understanding of electroweak symmetry breaking. It can be first achieved at the ILC\pcite{Behnke2013} at $\sqrt{s}=250\rm ~GeV$ via the Higgs-strahlung production process $e^+e^-\rightarrow ZH$. The hadronic decay mode $Z\rightarrow \bar{q}q$ constitutes more than $65%$ of the total, a factor 10 more than $Z\rightarrow μμ$. An analysis based solely on the $Z$ jet pair information could thus lead to a high statistics and provide a minimum biased Higgs sample. A study of the feasibility of such analysis is shown here, bas…

Search for Extra Scalars Produced in Association with Muon Pairs at the ILC

We study the search for an extra scalar $S$ boson produced in association with the $Z$ boson at the International Linear Collider (ILC). The study is performed at center-of-mass energies of 250 GeV and 500 GeV based on the full simulation of the International Large Detector (ILD). In order to be as model-independent as possible, the analysis uses the recoil technique, in particular with the $Z$ boson decaying into a pair of muons. As a result, exclusion cross-section limits are given in terms of a scale factor $k$ with respect to the Standard Model Higgs-strahlung process cross section. These …

Full Simulation Study of the Higgs Branching Ratio into Tau Lepton Pairs at the ILC with $\sqrt{s} = 500$ GeV

We evaluate the expected measurement accuracy of the branching ratio of the Standard Model Higgs boson decaying into tau lepton pairs $h \to τ^+ τ^-$ at the ILC with a center-of-mass energy of $\sqrt{s} = 500$ GeV with a full simulation of the ILD detector. We assume a Higgs mass of $M_h = 125$ GeV, a branching ratio of $\mathrm{BR}(h \to τ^+ τ^-) = 6.32 \%$, beam polarizations of $P(e^+, e^-) = (-0.8,+0.3)$, and an integrated luminosity of $\int L dt = 500 \mathrm{fb^{-1}}$. The Higgs-strahlung process $e^+ e^- \to Zh$ with $Z \to q \overline{q}$ and the $WW$-fusion process $e^+ e^- \to ν\ove…

未来$e^+e^-$对撞机上的希格斯自耦合测量

Higgs self-coupling measurement at future $e^+e^-$ colliders

本研究依托ILD探测器的Geant4模拟，分析未来500 GeV质心系能量线性$e^+e^-$对撞机通过$e^+e^-\to ZHH$过程测量希格斯自耦合的能力，探索重建技术优化方案，并评估能量选择要求以支撑未来对撞机规划。