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In this paper we reported the first results of a novel symmetry test performed to check the standard model's prediction of maximal parity violation in nuclear P decay. The experiment measured the ratio R of the polarization of positrons emitted in opposite directions with respect to the nuclear spin and compared the result with the standard model prediction Ro. We have since come to realize that the small transverse components of the positron polarization accepted by the polarimeter make a non-negligible contribution to Ro. Our corrected result, which is presented in detail elsewhere[1], is (b+g) =0.0003~0.0058. This correction increases our 90% confidence level lower bound on the mass of an eventual right-handed gauge boson from 225 to 250 GeV/c, leaving our main conclusions unchanged.We thank Dr. J. Govaerts for calculations which show that the rotation of the positron spin in the magnetic fields of the apparatus has a negligible eAect on the final result.

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We measured 36 Ar(p ជ ,p 0 ) cross sections and analyzing powers for E p between 3.22 and 5.98 MeV, and used these data to deduce spin, parity, and widths of 17 levels in 37 K. Our results, combined with existing information on 37 Ca ␤ ϩ decay, yield information on the distribution of Fermi and Gamow-Teller strength in this decay. A Tϭ1/2 level lying 31 keV below the J ϭ3/2 ϩ , Tϭ3/2 analog of the 37 Ca ground state was found to have J ϭ3/2 ϩ . The relative proton widths of the two levels imply an isospin-mixing matrix-element of 4.84Ϯ0.43 keV. This agrees with the value 5.93 Ϫ0.65 ϩ0.23 keV extracted from the ␤ ϩ -decay intensities to the two levels, plus the Gamow-Teller to Fermi strength ratio for the 5018 keV level. We decompose the Gamow-Teller strength in 37 Ca decay into components feeding daughter levels with J ϭ1/2 ϩ , 3/2 ϩ , or 5/2 ϩ , and compare the results to theory. None of the available shell-model calculations gives a satisfactory account of the data. ͓S0556-2813͑97͒00602-X͔

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