我们研究了在LHC上用$p p \to t\bar{t}X$和$p p \to t/\bar{t} X$过程以及随后的$t \to W^+s$和$\bar{t} \to W^- \bar{s}$衰变产生的顶夸克测量CKM矩阵元$\vert V_{ts}\vert$的前景。我们坚持对$W^\pm$进行轻子标记，即$W^\pm \to \ell^\pm ν_\ell$（$\ell =e, μ, τ$），并分析信号过程$t \to W s$中预期的喷流剖面和来自衰变$t \to W b$的主导背景。为此，我们分析的$V0$（$K^0$和$Λ$）分布的$s$和$b$夸克喷注集中在这些粒子的能量和横向动量分布。从$t \to W b$分支发出的$V0$由于弱衰变$b \to c \to s$和$b$ -夸克喷流富含带电轻子而使衰变顶点从相互作用点移位。因此，在喷流中没有次级顶点和高能带电轻子提供了顶夸克衰变中额外的（$b$ -喷流与$s$ -喷流）区分。这些分布用于训练提升决策树（BDT）。使用BDT分类器和它的一个变体BDTD，它使用去相关变量，我们计算对应于信号（$t \to W s$）和背景（$t \to W b$）的BDT（D）响应函数。详细的模拟进行了我们与Monte Carlo发生器PYTHIA被用来估计的背景抑制与信号效率为三个代表性的LHC能量$\sqrt{s}=7$ TeV，10 TeV和14 TeV。我们认为，一个基准与10\%的信号（$t \to W s $）的效率和背景（$t \to W b$）的拒绝由一个因素$10^3$（由于预期值的比率$\vert V_{ts}\vert^2/\vert V_{tb} \vert^2 \simeq 1.6 \times 10^{-3}$所需）可以实现在LHC@14 TeV与10 FB $^{-1}$的综合光度。
英文摘要：
We study the prospects of measuring the CKM matrix element $\vert V_{ts}\vert$ at the LHC with the top quarks produced in the processes $p p \to t\bar{t}X$ and $p p \to t/\bar{t} X$, and the subsequent decays $t \to W^+s$ and $\bar{t} \to W^- \bar{s}$. We insist on tagging the $W^\pm$ leptonically, $W^\pm \to \ell^\pm ν_\ell$ ($\ell =e, μ, τ$), and analyse the anticipated jet profiles in the signal process $t \to W s$ and the dominant background from the decay $t \to W b$. To that end, we analyse the $V0$ ($K^0$ and $Λ$) distributions in the $s$- and $b$-quark jets concentrating on the energy and transverse momentum distributions of these particles. The $V0$s emanating from the $t \to W b$ branch have displaced decay vertexes from the interaction point due to the weak decays $b \to c \to s$ and the $b$-quark jets are rich in charged leptons. Hence, the absence of secondary vertexes and of the energetic charged leptons in the jet provide additional ($b$-jet vs. $s$-jet) discrimination in top quark decays. These distributions are used to train a boosted decision tree (BDT). Using the BDT classifier, and a variant of it called BDTD, which makes use of decorrelated variables, we calculate the BDT(D)-response functions corresponding to the signal ($t \to W s$) and background ($t \to W b$). Detailed simulations undertaken by us with the Monte Carlo generator PYTHIA are used to estimate the background rejection versus signal efficiency for three representative LHC energies $\sqrt{s}=7$ TeV, 10 TeV and 14 TeV. We argue that a benchmark with 10\% signal ($t \to W s $) efficiency and a background ($t \to W b$) rejection by a factor $10^3$ (required due to the anticipated value of the ratio $\vert V_{ts}\vert^2/\vert V_{tb} \vert^2 \simeq 1.6 \times 10^{-3}$) can be achieved at the LHC@14 TeV with an integrated luminosity of 10 fb$^{-1}$.
Testing the CKM unitarity at high energy via the $W^+W^-$ production at the LHC and future colliders
University of Trieste（的里雅斯特大学）；INFN, Sezione di Trieste（意大利国家核物理研究所的里雅斯特分部）；Laboratory of High-Energy and Computational Physics, NICPB（爱沙尼亚高等研究院高能计算物理实验室）；Institute of Computer Science, University of Tartu（塔尔图大学计算机科学研究所）
Prospects of LHC Higgs Physics at the end of Run III - Talk presented at the International Workshop on Future Linear Colliders (LCWS2016), Morioka, Japan, 5-9 December 2016. C16-12-05.4
Prospects for Higgs CP property measurements at the LHC - Talk presented at the International Workshop on Future Linear Colliders (LCWS2016), Morioka, Japan, 5-9 December 2016. C16-12-05.4
Prospect and implications of $cg\to bH^+\to b A W^+$ production at the LHC
我们研究了在大型强子对撞机上发现$cg\to bH^+\to b A W^+$过程的前景。在一般双Higgs模型（g2 HDM）中，由顶味变化中性Higgs耦合$ρ_{tc}$诱导的过程可能是由带电荷的$m_{H^+} > m_A + m_{W^+}$（其中$H^+$和$A$）和$CP$ -奇Higgs玻色子引起的.我们表明，$cg\to bH^+\to b A W^+$过程可以发现在LHC运行3，而完整的运行2的数据在手可以通过搜索相同的符号双轻子的最终状态显着约束的参数空间。该过程对CMS报告的$m_A\approx 400$ GeV处$gg\to A \to t \bar t$过量的暗示具有独特的意义。当与其他现有的约束条件相结合时，$cg\to bH^+\to b A W^+$过程基本上可以排除g2 HDM对这种过度的解释。
Prospects for toponium formation at the LHC in the single-lepton mode
Sorbonne Université et CNRS（索邦大学与法国国家科学研究中心）；KEK Theory Center（高能加速器研究机构理论中心）；Xi’an University of Architecture and Technology（西安建筑科技大学）；The University of Osaka（大阪大学）
