[en] In this paper, I present the most recent hadron spectroscopy results stemming from in-flight p-barp reactions at LEAR. In the mass range from approximately 2.0 to 2.43 GeV, scans for both broad and narrow resonances have been performed. The PS185, Crystal Barrel and Jetset experiments figure prominently in the results presented. Particular attention is given to the latest searches for the ξ(2220)

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[en] We report a measurement of the positive muon lifetime to a precision of 1.0 ppm; it is the most precise particle lifetime ever measured. The experiment used a time-structured, low-energy muon beam and a segmented plastic scintillator array to record more than 2x10¹² decays. Two different stopping target configurations were employed in independent data-taking periods. The combined results give τ_μ⁺(MuLan)=2 196 980.3(2.2) ps, more than 15 times as precise as any previous experiment. The muon lifetime gives the most precise value for the Fermi constant: G_F(MuLan)=1.166 378 8(7)x10^-5 GeV^-2 (0.6 ppm). It is also used to extract the μ^-p singlet capture rate, which determines the proton's weak induced pseudoscalar coupling g_P.

[en] The mean life of the positive muon has been measured to a precision of 11 ppm using a low-energy, pulsed muon beam stopped in a ferromagnetic target, which was surrounded by a scintillator detector array. The result, τ_μ=2.197 013(24) μs, is in excellent agreement with the previous world average. The new world average τ_μ=2.197 019(21) μs determines the Fermi constant G_F=1.166 371(6)x10^-5 GeV^-2 (5 ppm). Additionally, the precision measurement of the positive-muon lifetime is needed to determine the nucleon pseudoscalar coupling g_P