论文标题
ILC的$HγZ$耦合的研究
Study of the $hγZ$ coupling at the ILC
论文作者
论文摘要
我们研究$HγZ$耦合，这是标准模型（SM）中循环诱导的耦合，以探测新的物理。在基于SM有效现场理论的全球拟合度中，SM $HγZ$耦合的测量可以提供非常有用的约束，特别是对于$ HZZ $和$ HWW $耦合的精确确定。在国际线性对撞机（ILC）中，有两种直接研究$HγZ$耦合的方法：一种是测量$ H \ \ \ \ \γz$ decay的分支比，另一种是测量$ e^+e^+e^ - \ toHγ$过程的横截面。我们已经在250 GEV ILC上对$ e^+e^ - \ toHγ$过程进行了完整的模拟研究，假设国际大型检测器（ILD）收集了2个AB $^{ - 1} $数据。预期的1 $σ$在有效的$HγZ$耦合（$ζ_{az} $）上结合了$ e^+e^ - \ toHγ$的横截面的测量值，然后是$ h \ to b \ bar {b {b} $，$ h \ $ h \ to $ h \ toγz$ brchanding率为$ 0.00.0015 em00 $ 000.0015 <^a a。完全hadronic $ h \ to ww^*$通道中信号横截面的预期意义为0.09 $σ$的光束极化为$ p（e^ - ，e^+）=（ - 80 \％，+30 \％）$。
We study the $h γZ$ coupling, which is a loop induced coupling in the Standard Model (SM), to probe new physics. In a global fit based on the SM Effective Field Theory, measurement of the SM $h γZ$ coupling can provide a very useful constraint, in particular for the precise determination of $hZZ$ and $hWW$ couplings. At the International Linear Collider (ILC), there are two direct ways to study the $h γZ$ coupling: one is to measure the branching ratio of the $h \to γZ$ decay and the other to measure the cross section for the $e^+e^- \to h γ$ process. We have performed a full simulation study of the $e^+e^- \to h γ$ process at the 250 GeV ILC, assuming 2 ab$^{-1}$ data collected by the International Large Detector (ILD). The expected 1$σ$ bound on the effective $hγZ$ coupling ($ζ_{AZ}$) combining measurements of the cross section for $e^+e^- \to h γ$ followed by $h \to b \bar{b}$ and the $h \to γZ$ branching ratio is $-0.0015<ζ_{AZ}<0.0015$. The expected significance for the signal cross section in the fully hadronic $h \to WW^*$ channel is 0.09 $σ$ for beam polarizations of $P(e^-,e^+)=(-80\%,+30\%)$.
