Mean life of the positive muon

Electroweak precision tests of the Standard Model after the discovery of the Higgs boson

“…Older experiments [289,290] used a continuous incoming muon beam and therefore had to reduce the rate in order to avoid miscorrelations of decay positrons with their parent muons. Hence these measurements were limited by the available data statistics.…”

Precise Muon Lifetime Measurement with a Pulsed Beam at the RIKEN-RAL Muon Facility

“…Therefore, the precise measurement of τ µ improves the G F accuracy. The most accurate value of τ µ was obtained at TRIUMF in 1984 [3]. They obtained τ µ = 2.19695 ± 0.00006 µs (27 ppm) and the PDG average is 2.19703 ± 0.00004 µs (18 ppm) [1].…”

“…In the previous measurements [3,4], an accuracy of τ µ was limited statistically since only a few muons were observed in a time window in order to minimize a count-loss due to pile-up signals. To improve the τ µ accuracy within a realistic beam-time, it is essential to increase data accumulation rate.…”

Precise measurement of the positive muon lifetime at the RIKEN-RAL muon facility

“…We have observed ∼ 10 10 muon decay events and our final goal is to improve the τ accuracy at the level of 10 ppm. The muon lifetime measurement has a long history and the most accurate value of the τ µ was obtained at TRIUMF in 1984 [3]. They determined τ µ = 2.19695 ± 0.00006 µs [1].…”

“…In the previous measurements [3,4] accuracy of τ µ was limited, since they observed only a few muons in a time window in order to decrease a count-loss due to the pile-up. To improve the τ µ accuracy within a realistic beam-time, it is essential to increase the data accumulation rate.…”