Hadronic Invariant Mass Spectrum in B → X u lν Decay with Lepton Energy Cut
نویسندگان
چکیده
We discuss the implications of charged lepton energy cut to the hadronic invariant mass spectrum in charmless semileptonic B decays. Charged-lepton energy cut is inevitable in order to remove secondary leptonic events such as b → c, τ → l, and to identify the chaged leptons at detectors experimentally. We consider three possible lepton energy cuts, Ecuts l = 0.6, 1.5, 2.3 GeV, and found that with the most probable cuts Ecut l = 1.5 GeV and M max X = 1.5 (1.86) GeV, 45 ∼ 60% (58 ∼ 67%) of decay events survive. Therefore, B → Xulν decay events can be efficiently distinguished from B → Xclν decay events. We also discuss the possible model dependence on the results. Typeset using REVTEX ∗[email protected], http://phya.yonsei.ac.kr/ ̃cskim/
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