论文标题
搜索与$τ^+τ^ - $ e^+e^ - $ e^+e^ - $ nihihilation在质量中心能量附近的$ e^+e^-10.58
Search for a dark leptophilic scalar produced in association with $τ^+τ^-$ pair in $e^+e^-$ annihilation at center-of-mass energies near 10.58 GeV
论文作者
论文摘要
深色的瘦量标量$(ϕ_l)$是一个假设的粒子,仅将其伴随到瘦小的而不是夸克。我们在$ e^+ e^ - \ toτ^+τ^ - ϕ_l,〜d ϕ_l \ to \ ell^+ \ ell^ - 〜(\ ell = e,μ)$过程中使用626〜 \ el^$ process进行了626〜 \ el^$ process的搜索。我们使用新型的多类多元事件分类器来验证数据中具有多个控制区域的背景。在没有信号的情况下,我们在90 \%置信度的上限上引用了$ ϕ_l $和Leptons之间的耦合。我们以盲方法获得的界限比以前的限制更为19 \%,在质量范围内平均$ 0.04 \ leq m_ {ϕ_l} \ leq 6.5〜 \ gev $。我们将参数空间排除在4〜 \ gev以下,通过测量MUON的异常磁矩所青睐。
A dark leptophilic scalar $(ϕ_L)$ is a hypothetical particle that couples only to leptons rather than quarks. We report on a search for $ϕ_L$ in the $e^+e^- \to τ^+ τ^- ϕ_L, ~ϕ_L \to \ell^+ \ell^- ~(\ell = e, μ)$ process using 626~\invfb of data collected by the Belle experiment near the \Y4S resonance. We validate the backgrounds with multiple control regions in data, using a novel multiclass multivariate event classifier. In absence of a signal, we quote upper limits at the 90\% confidence level on the coupling between $ϕ_L$ and leptons. Our bounds, obtained in a blinded approach, are 19\% more constraining than the previous limits, averaged over the mass range $0.04 \leq m_{ϕ_L} \leq 6.5~\gev$. We exclude the parameter space below 4~\gev favored by measurement of the anomalous magnetic moment of the muon.