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We report a measurement of the ortho-para transition rate in the p$��$p molecule. The experiment was conducted at TRIUMF via the measurement of the time dependence of the 5.2 MeV neutrons from muon capture in liquid hydrogen. The measurement yielded an ortho-para rate $��_{op} = (11.1 \pm 1.7 \pm^{0.9}_{0.6}) \times 10^4$ s$^{-1}$ that is substantially larger than the earlier result of Bardin {\it et al.} We discuss the striking implications for the proton's induced pseudoscalar coupling $g_p$., 4 pages, 3 figures, submitted to Phys. Rev. Lett

We have set limits on contributions of scalar interactions to nuclear beta decay. A magneto-optical trap (MOT) provides a localized source of atoms suspended in space, so the low-energy recoiling nuclei can freely escape and be detected in coincidence with the beta. This allows reconstruction of the neutrino momentum, and the measurement of the beta-neutrino correlation, in a more direct fashion than previously possible. The beta-neutrino correlation parameter of the 0+ to 0+ pure Fermi decay of 38mK is $\tilde{a}$=0.9981+-0.0030+-0.0037, consistent with the standard model prediction a=1., 4 pages, 3 figures, accepted by Phys. Rev. Lett., centroid changed

We report a measurement of the longitudinal alignment $A_L$ of the recoil nucleus in the $\mu^- + ^{14}$N$(1^+, 0)$ $\to$ $\nu_{\mu} + ^{14}$C$(2^+, 7012)$ transition. The experiment was performed on the M9B beamline at the TRIUMF cyclotron via the measurement of the Doppler lineshape of the subsequent $^{14}$C$(2^+, 7012)$ $\to$ $^{14}$C$(0^+, 0)$ gamma-rays. We compare our result $A_L = 0.60 \pm 0.11$ to various model calculations, and discuss the sensitivity to the induced pseudoscalar coupling, second-forbidden effects and $2 \hbar \omega$ wavefunction admixtures., Comment: 22 pages, 3 tables, 5 figures, submitted to Phys. Rev. C

We report measurements of $\gamma$--ray spectra from muon capture on $^{35}$Cl. For the allowed Gamow--Teller transitions to the $^{35}$S$(2939, 3/2^+)$ state and the $^{35}$S$(3421, 5/2^+)$ state we obtained their capture rates, hyperfine dependences and $\gamma$--$\nu$ correlation coefficients. The capture rates and hyperfine dependences were compared to shell model calculations using the complete 1s--0d space and the universal SD interaction. With $g_p / g_a = 6.7$ and $g_a = -1.00$ (or $g_a = -1.26$) we found agreement of the model and the data at the 1--2 $\sigma$ level. However, we caution that the transitions are sensitive to $\ell = 2$ forbidden matrix elements., Comment: 29 pages, 9 figures, submitted to Phys. Rev. C