LIMIT ON ${{\boldsymbol \mu}^{-}}$ $\rightarrow$ ${{\boldsymbol e}^{-}}$ CONVERSION

Forbidden by lepton family number conservation.

${\boldsymbol \sigma (}$ ${{\boldsymbol \mu}^{-}}$ ${}^{}\mathrm {Pb}$ $\rightarrow$ ${{\boldsymbol e}^{-}}{}^{}\mathrm {Pb}{)}$ / ${\boldsymbol \sigma (}$ ${{\boldsymbol \mu}^{-}}$ ${}^{}\mathrm {Pb}$ $\rightarrow$ capture${)}$ INSPIRE search

VALUE CL% DOCUMENT ID TECN  COMMENT
$\bf{<4.6 \times 10^{-11}}$ 90
HONECKER
1996
SPEC SINDRUM II
• • • We do not use the following data for averages, fits, limits, etc. • • •
$<4.9 \times 10^{-10}$ 90
AHMAD
1988
TPC TRIUMF
  Conservation Laws:
LEPTON FAMILY NUMBER
  References:
HONECKER 1996
PRL 76 200 Improved Limit on the Branching Ratio of ${{\mathit \mu}}$ $\rightarrow$ ${{\mathit e}}$ Conversion on Lead
AHMAD 1988
PR D38 2102 Search for Muon Electron and Muon Positron Conversion