Davidson Sacha, Mangano Michelangelo L, Perries Stéphane, Sordini Viola
IPNL, CNRS/IN2P3, 4 rue E. Fermi, 69622 Villeurbanne Cedex, France ; Université Lyon 1, Villeurbanne, France ; Université de Lyon, 69622 Lyon, France.
CERN PH-TH, 1211 Geneva 23, Switzerland.
Eur Phys J C Part Fields. 2015;75(9):450. doi: 10.1140/epjc/s10052-015-3649-5. Epub 2015 Sep 25.
We consider lepton-flavour violating decays of the top quark, mediated by 4-fermion operators. We compile constraints on a complete set of SU(3) [Formula: see text] U(1)-invariant operators, arising from their loop contributions to rare decays and from HERA's single-top search. The bounds on -[Formula: see text] flavour change are more restrictive than on [Formula: see text]-[Formula: see text]; nonetheless the top could decay to a jet [Formula: see text] with a branching ratio of order [Formula: see text]. We estimate that the currently available LHC data (20 fb[Formula: see text] at 8 TeV) could be sensitive to [Formula: see text]+ jet) [Formula: see text], and we extrapolate that 100 fb[Formula: see text] at 13 TeV could reach a sensitivity of [Formula: see text].
我们考虑由四费米子算符介导的顶夸克轻子味违反衰变。我们整理了一组完整的SU(3)×U(1)不变算符的约束条件,这些约束来自它们对罕见衰变的圈贡献以及HERA的单顶夸克搜索。对τ−μ味改变的限制比对μ−e味改变的限制更严格;尽管如此,顶夸克仍可能以约10−12的分支比衰变为一个喷注加τ。我们估计,目前可用的大型强子对撞机数据(8 TeV下20 fb−1)可能对Br(t→j+τ)敏感,并且我们推断13 TeV下100 fb−1可以达到10−13的灵敏度。