Title: Single lepton charge asymmetries in $t \bar t$ and $t \bar t γ$ production at the LHC Show Chinese title

Title: 单轻子电荷不对称性在LHC上$t \bar t$ 和$t \bar t γ$ 产生中的研究

Abstract: We discuss lepton charge asymmetries in $t \bar t$ and $t \bar t \gamma$ production at the LHC, which can be measured in the semileptonic decay channel $t \bar t \to W^+ b \, W^- \bar b \to \ell^+ \nu b \, q \bar q' \bar b$ (or the charge conjugate). Considering several variants of a new physics scenario with a light colour octet, it is seen that for $t \bar t$ these asymmetries may have a sensitivity competitive with the dilepton asymmetry already measured. For $t \bar t \gamma$ the new leptonic asymmetries, as well as the $t \bar t$ charge asymmetry, will reach their full potential with the high luminosity LHC upgrade. These asymmetries can pinpoint deviations at the $3\sigma-4\sigma$ level for new physics scenarios where the charge asymmetries already measured in $t \bar t$ production agree within $1\sigma$. Show Chinese abstract

Abstract: 我们讨论在大型强子对撞机（LHC）上$t \bar t$和$t \bar t \gamma$产生中的轻子电荷不对称性，这可以在半轻子衰变通道$t \bar t \to W^+ b \, W^- \bar b \to \ell^+ \nu b \, q \bar q' \bar b$（或其电荷共轭）中进行测量。 考虑到一种新的物理情景的多种变体，其中包含一个轻色八重态，可以看出对于$t \bar t$这些不对称性可能具有与已测量的二轻子不对称性相竞争的灵敏度。 对于$t \bar t \gamma$新的轻子不对称性以及$t \bar t$的电荷不对称性，将在高亮度 LHC 升级后发挥其全部潜力。 这些不对称性可以精确定位在$3\sigma-4\sigma$层次上的偏差，对于新物理情景而言，其中在$t \bar t$产生中已经测量的电荷不对称性在$1\sigma$范围内一致。