tau - Particle Data Group

Citation: K. Nakamura et al. (Particle Data Group), JP G 37, 075021 (2010) and 2011 partial update for the 2012 edition (URL: http://pdg.lbl.gov)
1 BARATE 99R combine the BARATE 98E and BARATE 99K bounds to obtain this value.
2 BARATE 99K measure K 0 ’s by detecting K 0’s in hadron calorimeter.
L
3 BARATE 98E reconstruct K 0 ’s by using K 0 → π + π − decays.
S
Γ ( π − K 0 K 0 ) ν τ /Γtotal
Γ 46 /Γ = (2Γ 47 +Γ 48 )/Γ
Data marked “avg” are highly correlated with data appearing elsewhere in the Listings,
and are therefore used for the average given below but not in the overall fits. “f&a”
marks results used for the fit and the average.
VALUE (%) EVTS DOCUMENT ID TECN COMMENT
0.17 ±0.04 OUR FIT Error includes scale factor of 1.6.
•••We use the following data for averages but not for fits. •••
0.153±0.030±0.016 avg 74 1 BARATE 98E ALEP 1991–1995 LEP runs
•••We do not use the following data for averages, fits, limits, etc. •••
0.31 ±0.12 ±0.04 2 ACCIARRI 95F L3 1991–1993 LEP runs
1 BARATE 98E obtain this value by adding twice their B(π − K 0 K 0 S S ν τ ) value to their
B(π − K 0 S K0 L ν τ )value.
2 ACCIARRI 95F assume B(π − K 0 K 0 S S ν)= B(π− K 0 S K0 L ν) = 1/2B(π− K 0 S K0 L ν).
Γ ( π − K 0 S K 0 S ν ) τ /Γtotal Γ 47 /Γ
Bose-Einstein correlations might make the mixing fraction different than 1/4.
VALUE (units 10 −4 ) EVTS DOCUMENT ID TECN COMMENT
(2.4+-0.5) OUR FIT
(2.4+-0.5) OUR AVERAGE
2.6±1.0±0.5 6 BARATE 98E ALEP 1991–1995 LEP runs
2.3±0.5±0.3 42 COAN 96 CLEO E ee cm ≈ 10.6 GeV
Γ ( π − K 0 S K 0 L ν ) τ /Γtotal Γ 48 /Γ
VALUE (units 10 −4 ) EVTS DOCUMENT ID TECN COMMENT
11 ±4 OUR FIT Error includes scale factor of 1.7.
10.1±2.3±1.3 68 BARATE 98E ALEP 1991–1995 LEP runs
Γ ( π − K 0 K 0 π 0 ) ν τ /Γtotal Γ 49 /Γ
VALUE DOCUMENT ID TECN COMMENT
(0.31±0.23) × 10 −3 1 BARATE 99R ALEP 1991–1995 LEP runs
1 BARATE 99R combine BARATE 98E Γ(π − K 0 K 0 S S π0 ν τ )/Γ total and
Γ(π − K 0 S K0 L π0 ν τ )/Γ total measurements to obtain this value.
Γ ( π − K 0 S K 0 )
S π0 ν τ /Γtotal Γ 50 /Γ
VALUE (units 10 −4 ) CL% DOCUMENT ID TECN COMMENT