Bounding the $Z^\prime tc$ coupling from $D^{0}-\bar{D^{0}}$ mixing and single top production at the ILC

在国际直线对撞机（ILC）上基于爱因斯坦-嘉当引力框架搜寻暗物质

Search for dark matter in the framework of Einstein-Cartan gravity at the International Linear Collider (ILC)

本文研究在ILC上基于爱因斯坦-嘉当引力模型产生暗物质费米子与暗规范玻色子A′的过程，通过模拟双μ子对和丢失横能量信号，为挠率场等模型参数设定质量上限。

Probing the seesaw mechanism at the 250 GeV ILC

We consider a gauged U(1)$_{B-L}$ (Baryon-minus-Lepton number) extension of the Standard Model (SM), which is anomaly-free in the presence of three Right-Handed Neutrinos (RHNs). Associated with the U(1)$_{B-L}$ symmetry breaking the RHNs acquire their Majorana masses and then play the crucial role to generate the neutrino mass matrix by the seesaw mechanism. Towards the experimental confirmation of the seesaw mechanism, we investigate a RHN pair production through the U(1)$_{B-L}$ gauge boson ($Z^\prime$) at the 250 GeV International Linear Collider (ILC). The $Z^\prime$ gauge boson has been …

Probing heavy Majorana neutrino pair production at ILC in a $U(1)_{\rm B-L}$ extension of the Standard Model

We consider a gauged B$-$L (Baryon number minus Lepton number) extension of the Standard Model (SM), which is anomaly free in the presence of three SM singlet Right Handed Neutrinos (RHNs). Associated with the $U(1)_{\rm B-L}$ gauge symmetry breaking, the RHNs acquire Majorana masses and then with the electroweak symmetry breaking, tiny Majorana masses for the SM(-like) neutrinos are naturally generated by the seesaw mechanism. As a result of the seesaw mechanism, the heavy mass eigenstates which are mainly composed of the SM-singlet RHNs obtain suppressed electroweak interactions through smal…

Chargino production at the ILC

The lighter chargino, $\widetildeχ_1^{\pm}$, is a prime candidate to be the next-to-lightest SUSY particle (the NLSP). Several analyses of $\widetildeχ_1^{\pm}$ pair-production at the ILC, at specific model-points, have been performed, showing that detection and property-determination is possible, even for very difficult cases. However, no recent studies have evaluated the reach of the ILC to detect $\widetildeχ_1^{\pm}$ pair production in general. In this study, cross sections for $\widetildeχ_1^{\pm}$ pair production at the ILC were evaluated within a wide range of parameters. The aim was to…

Four Leptons Production in $e^-$ $e^+$ Collisions from 3-3-1 Model

We study the process $e^- + e^+ \to e^+ + e^+ + e^- + e^-$ for ILC and CLIC energy regimes, in the minimal 3-3-1 model framework. The main contributions, for the production of two bileptons each one decaying into two same-sign leptons, come from s-channel annihilation ({\it via} $γ, Z$ and ${Z^\prime}$) and t-channel electron exchange. We evaluate the number of events for an extra neutral gauge boson mass $M_{Z^\prime}$ in the range 1 TeV to 3 TeV. We compare some distributions from 3-3-1 model with the Standard Model background in order to extract a possible signature of the contribution of b…

A Z-prime interpretation of Bd->K*mu+mu- data and consequences for high energy colliders

In this note, I examine the possible consequences for high energy colliders of a Z-prime interpretation of the LHCb anomaly observed in the K*mu+mu- final state. Two examples are elaborated in the framework of the so-called 331 model. In the first one it is shown that LEP2 provides the tightest lower mass limit for the Z-prime boson, above 8 TeV, while in the second one the lower mass limit is set by ATLAS/CMS to about 3 TeV. It is then shown that precision measurements at ILC 500 GeV can fully explore the underlying structure of the model by measuring the fermion final states separately: lept…

线性对撞机上极化束的矢量轻子对产生：灵敏度投影和手征可观测量

Vector-Like Lepton Pair Production With Polarized Beams at Linear Colliders:Sensitivity Projections and Chirality Observables

研究极化未来线性对撞机上矢量轻子双荷的产生，通过带电和中性通道的截面及手征可观测量，展示束极化对双荷电弱结构的诊断能力。

在带逆跷跷板机制的规范U$(1)^\prime$模型中通过冻结注入产生惰性中微子暗物质

Freeze-in production of sterile neutrino dark matter in a gauged U$(1)^\prime$ model with inverse seesaw

本文研究带逆跷跷板机制的无反常U$(1)^\prime$模型中赝狄拉克惰性中微子暗物质的冻结注入产生，通过遗迹丰度和多种对撞机及前沿实验约束$U(1)^\prime$荷、$Z^\prime$质量与耦合，并解释INTEGRAL卫星观测到的511 keV谱线。

Flavor Changing Neutral Currents involving Heavy Quarks with Four Generations

We study various FCNC involving heavy quarks in the Standard Model (SM) with a sequential fourth generation. After imposing $B\to X_sγ$, $B\to X_sl^+l^-$ and $Z\to b\bar{b}$ constraints, we find ${\cal B}(Z\to s\bar{b}+\bar{s}b)$ can be enhanced by an order of magnitude to $10^{-7}$, while $t\to cZ, cH$ decays can reach $10^{-6}$, which are orders of magnitude higher than in SM. However,these rates are still not observable for the near future.With the era of LHC approaching, we focus on FCNC decays involving fourth generation $b^\prime$ and $t^\prime$ quarks. We calculate the rates for loop in…

通过散射测量实验探测手性$Z^\tau$规范玻色子

Probing for chiral $Z^\prime$ gauge boson through scattering measurement experiments

针对标准模型无法解释中微子质量的问题，研究含手性$Z^\tau$的$U(1)_X$扩展模型，结合多类实验数据推导约束并评估未来实验的探测潜力。