Pith. sign in

REVIEW 6 cited by

Detailed Report of the MuLan Measurement of the Positive Muon Lifetime and Determination of the Fermi Constant

Not yet reviewed by Pith; the record is open.

This paper has not been read by Pith yet. Machine review is queued; the pith claim, tier, and objections will appear here once it completes.

SPECIMEN: schema-true, not a live event

T0 review · schema-true

One-sentence machine reading of the paper's core claim.

pith:XXXXXXXX · record.json · timestamp

arxiv 1211.0960 v1 pith:SK46NJRM submitted 2012-11-05 hep-ex nucl-exphysics.ins-det

Detailed Report of the MuLan Measurement of the Positive Muon Lifetime and Determination of the Fermi Constant

classification hep-ex nucl-exphysics.ins-det
keywords lifetimemeasurementmuonmulantargetconstantdetailedfermi
verification ladder T0 review T1 audit T2 compute T3 formal T4 reserved
0 comments
read the original abstract

We present a detailed report of the method, setup, analysis and results of a precision measurement of the positive muon lifetime. The experiment was conducted at the Paul Scherrer Institute using a time-structured, nearly 100%-polarized, surface muon beam and a segmented, fast-timing, plastic scintillator array. The measurement employed two target arrangements; a magnetized ferromagnetic target with a ~4 kG internal magnetic field and a crystal quartz target in a 130 G external magnetic field. Approximately 1.6 x 10^{12} positrons were accumulated and together the data yield a muon lifetime of tau_{mu}(MuLan) = 2196980.3(2.2) ps (1.0 ppm), thirty times more precise than previous generations of lifetime experiments. The lifetime measurement yields the most accurate value of the Fermi constant G_F (MuLan) = 1.1663787(6) x 10^{-5} GeV^{-2} (0.5 ppm). It also enables new precision studies of weak interactions via lifetime measurements of muonic atoms.

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.

Forward citations

Cited by 6 Pith papers

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score.

  1. Ab initio calculations of parity-violating electron scattering off $^{48}$Ca and $^{208}$Pb

    nucl-th 2026-06 unverdicted novelty 8.0

    Ab initio chiral EFT calculations of parity-violating asymmetries for 48Ca and 208Pb show mild tension with data and infer a neutron skin of 0.187(25)(18) fm for 208Pb.

  2. Pion $\beta$ decay and $\tau\to\pi\pi\nu_\tau$ beyond leading logarithms

    hep-ph 2026-02 conditional novelty 7.0

    Pion β decay and τ→ππν short-distance radiative corrections are matched at NLL accuracy with evanescent-scheme dependence cancelled, giving Δ_RC^{πℓ}=0.03403(11) and a τ-HVP isospin-breaking shift of −0.07(4)×10^-10.

  3. Improved Standard-Model predictions for $\eta^{(\prime)}\to \ell^+ \ell^-$

    hep-ph 2025-12 accept novelty 5.0

    Updated SM predictions yield Br(η→e⁺e⁻)=5.37(4)(2)[4]×10⁻⁹, Br(η→μ⁺μ⁻)=4.54(4)(2)[4]×10⁻⁶, Br(η'→e⁺e⁻)=1.80(2)(3)[3]×10⁻¹⁰, and Br(η'→μ⁺μ⁻)=1.22(2)(2)[3]×10⁻⁷, with a mild 1.6σ tension in the η→μ⁺μ⁻ channel.

  4. Muon lifetime and Fermi constant: an update

    hep-ph 2026-07 accept novelty 4.5

    Updated Δq = (−4 384 678 ± 34)×10^{-9} reduces theory error on the muon lifetime by an order of magnitude and gives G_F = 1.166 378 59(59)×10^{-5} GeV^{-2}.

  5. Weinberg Angle, Neutron Abundance in BBN, and Lifetime

    hep-ph 2026-03 conditional novelty 4.0

    Small shifts in the Weinberg angle change the effective Fermi constant enough to visibly alter the neutron abundance at BBN onset and the neutron lifetime in the early-Universe plasma.

  6. Muon beams towards muonium physics: progress and prospects

    hep-ex 2026-01 unverdicted novelty 1.0

    A review summarizing recent progress in high-intensity polarized muon beams for precision muonium physics, new physics searches, and materials science applications.