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We have set limits on contributions of scalar interactions to nuclear beta decay. A magneto-optical trap 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-nu correlation, in a more direct fashion than previously possible. The beta-nu correlation parameter of the 0(+)-->0(+) pure Fermi decay of (38)K(m) is a =0.9981+/-0.0030+0.0032 / -0.0037, consistent with the standard model prediction a =1.

The (n, p) reaction has been studied on the nuclei V and Co at an energy of 198 MeV. Spectra were measured at laboratory angles of 0, 4, 8', l2', 16', and 20' up to an excitation energy of 35 MeV in the Anal nuclei Ti and Fe. A multipole analysis of the data up to 30 MeV was carried out to identify Gamow-Teller (GT) (AL = 0, AJ = 1+) and spin-dipole (AL = 1, AJ = 0, 1,2 ) strengths. GT strength is concentrated in a resonance with centroid energy of 5.2 MeV in Ti and 4.1 MeV in Fe. The spin-dipole strength appears as a broad resonance with centroid energy about 16 MeV in both nuclei. Shell model calculations of the GT strength reproduce the energy distribution reasonably well, but the calculated strength exceeds the measurement by a factor of about 4.

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An experimental method is presented for a reasonably precise, direct measurement of the velocity of light using simple apparatus. The method is based on the result that the Fourier transform of a pair of identical pulses yields a frequency spectrum with zeros which are simply related to the time separation of the pulses. The principal pieces of apparatus required for the experiment are a photomultiplier and high-voltage power supply, and a short-wave radio receiver. With this relatively simple equipment and path lengths of fifty to one hundred feet, c may be readily measured to an accuracy of 1% or better.