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Limits on Coupling of ${{\mathit \mu}}$ to ${{\mathit \nu}_{{{x}}}}$ as Function of ${\mathit m}_{{{\mathit \nu}_{{{x}}}}}$

Limits on $\vert \mathit U_{{{\mathit \tau}}\mathit x}\vert ^2$ as a Function of ${\mathit m}_{{{\mathit \nu}_{{{x}}}}}$

INSPIRE JSON (beta) PDGID:

VALUE

CL%

DOCUMENT ID

TECN

COMMENT

• • We do not use the following data for averages, fits, limits, etc. • •

$<0.01$

90

CHRM

${\mathit m}_{{{\mathit \nu}_{{{x}}}}}$=45 MeV

$<1.4 \times 10^{-4}$

90

CHRM

${\mathit m}_{{{\mathit \nu}_{{{x}}}}}$=180 MeV

$<0.025$

90

${\mathit m}_{{{\mathit \nu}_{{{x}}}}}$=45 MeV

$<0.002$

90

${\mathit m}_{{{\mathit \nu}_{{{x}}}}}$=140 MeV

$<2 \times 10^{-5}$

95

DLPH

${\mathit m}_{{{\mathit \nu}_{{{x}}}}}$=6 GeV

$<3 \times 10^{-5}$

95

DLPH

${\mathit m}_{{{\mathit \nu}_{{{x}}}}}$=50 GeV

$<6.2 \times 10^{-8}$

95

L3

${\mathit m}_{{{\mathit \nu}_{{{x}}}}}$=20 GeV

$<5.1 \times 10^{-10}$

95

L3

${\mathit m}_{{{\mathit \nu}_{{{x}}}}}$=40 GeV

$\text{all values ruled out}$

95

MRK2

${\mathit m}_{{{\mathit \nu}_{{{x}}}}}$ $<$ $19.6$ GeV

$<1 \times 10^{-10}$

95

MRK2

${\mathit m}_{{{\mathit \nu}_{{{x}}}}}$ = $22$ GeV

$<1 \times 10^{-11}$

95

MRK2

${\mathit m}_{{{\mathit \nu}_{{{x}}}}}$ = $41$ GeV

$\text{all values ruled out}$

95

ALEP

${\mathit m}_{{{\mathit \nu}_{{{x}}}}}$= $25.0-42.7$ GeV

$<1 \times 10^{-13}$

95

ALEP

${\mathit m}_{{{\mathit \nu}_{{{x}}}}}$= $42.7-45.7$ GeV

$<0.05$

80

HRS

${\mathit m}_{{{\mathit \nu}_{{{x}}}}}=2.5$ GeV

$<9 \times 10^{-5}$

80

HRS

${\mathit m}_{{{\mathit \nu}_{{{x}}}}}=4.5$ GeV

¹	ORLOFF 2002 use the negative result of a search for neutral particles decaying into two electrons performed by CHARM to get these limits for a mostly isosinglet heavy neutrino.

²	ABREU 1997I long-lived ${{\mathit \nu}_{{{x}}}}$ analysis. Short-lived analysis extends limit to lower masses with decreasing sensitivity.

³	BURCHAT 1990 includes the analyses reported in JUNG 1990, ABRAMS 1989C, and WENDT 1987.

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