Search for a nearly degenerate lepton doublet (L-,L0).
نویسندگان
چکیده
. We have searched for a heavy charged lepton with an associated neutrino of nearly the same mass in e+eannihilation data taken with the Mark II detector at a centerof-mass energy of 29 GeV. In order to suppress contamination from conventional two.photon reactions, this analysis uses a novel, radiative-tagging technique. Requiring . the presence of an isolated, energetic photon allows a search for lepton doublets with mass splittings smaller than that previously accessible to experiment. No evidence for such a new lepton doublet has been found, enabling limits to be placed on allowed mass combinations. Mass splittings as low as 2 5 0 4 0 0 MeV/c2 are excluded for charged lepton masses between 500 MeV/c2 and 10 GeV/c2. Submitted to Physical Review D t This work was supported in part by the Department of Energy, contracts DE-AC03-76SF00515, DE-AC02-76ER03064, and DE-AC03-76SF-00098.
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ورودعنوان ژورنال:
- Physical review. D, Particles and fields
دوره 42 1 شماره
صفحات -
تاریخ انتشار 1990