Indirect Limits for Excited ${{\mathit e}}$ (${{\mathit e}^{*}}$)

INSPIRE   PDGID:
S054EXI
These limits make use of loop effects involving ${{\mathit e}^{*}}$ and are therefore subject to theoretical uncertainty.
VALUE (GeV) DOCUMENT ID TECN  COMMENT
• • We do not use the following data for averages, fits, limits, etc. • •
1
DORENBOSCH
1989
CHRM ${{\overline{\mathit \nu}}_{{\mu}}}$ ${{\mathit e}}$ $\rightarrow$ ${{\overline{\mathit \nu}}_{{\mu}}}{{\mathit e}}$ , ${{\mathit \nu}_{{\mu}}}$ ${{\mathit e}}$ $\rightarrow$ ${{\mathit \nu}_{{\mu}}}{{\mathit e}}$
2
GRIFOLS
1986
THEO ${{\mathit \nu}_{{\mu}}}$ ${{\mathit e}}$ $\rightarrow$ ${{\mathit \nu}_{{\mu}}}{{\mathit e}}$
3
RENARD
1982
THEO $\mathit g-2$ of electron
1  DORENBOSCH 1989 obtain the limit $\lambda {}^{2}_{\gamma }\Lambda {}^{2}_{{\mathrm {cut}}}/{{\mathit m}^{2}}_{{{\mathit e}^{*}}}$ $<$ $2.6$ (95$\%$ CL), where $\Lambda _{{\mathrm {cut}}}$ is the cutoff scale, based on the one-loop calculation by GRIFOLS 1986 . If one assumes that $\Lambda _{{\mathrm {cut}}}$ = 1 TeV and ${{\mathit \lambda}_{{\gamma}}}$ = 1, one obtains ${\mathit m}_{{{\mathit e}^{*}}}$ $>$ 620 GeV. However, one generally expects ${{\mathit \lambda}_{{\gamma}}}{}\approx{}{\mathit m}_{{{\mathit e}^{*}}}/\Lambda _{{\mathrm {cut}}}$ in composite models.
2  GRIFOLS 1986 uses ${{\mathit \nu}_{{\mu}}}$ ${{\mathit e}}$ $\rightarrow$ ${{\mathit \nu}_{{\mu}}}{{\mathit e}}$ and ${{\overline{\mathit \nu}}_{{\mu}}}$ ${{\mathit e}}$ $\rightarrow$ ${{\overline{\mathit \nu}}_{{\mu}}}{{\mathit e}}$ data from CHARM Collaboration to derive mass limits which depend on the scale of compositeness.
3  RENARD 1982 derived from $\mathit g-2$ data limits on mass and couplings of ${{\mathit e}^{*}}$ and ${{\mathit \mu}^{*}}$. See figures 2 and 3 of the paper.
References:
DORENBOSCH 1989
ZPHY C41 567 Experimental Results on Neutrino Electron Scattering
GRIFOLS 1986
PL 168B 264 Limits on Masses of Excited Electrons and Muons from Neutrino Scattering off Electrons
RENARD 1982
PL 116B 264 Limits on Masses and Couplings of Excited Electrons and Muons