Differential cross sections of elastic scattering of deuterons on the target nuclei 'Al, Y, ' Sn, and Pb were measured at Ed --58.7 MeV and Ed --85 MeV. "Best-fit" parameters in terms of the phenomenological optical model were extracted from the data including in addition differential cross section and analyzing power data from the literature. A set of global optical potential parameters is derived.

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The total cross section for the reaction pp-*ppn Q was measured at nine center-of-mass energies from 1.5 to 23 MeV above threshold. The experiment was carried out with the Indiana Cooler, a recently constructed storage ring. The experimental advantages of an electron-cooled proton beam were utilized. The data cover an energy range where only the lowest possible angular momentum state contributes in the exit channel. The measured energy dependence of the total cross section is not compatible with that predicted by models of s-wave pion production and rescattering. PACS numbers: 25.10,+s, 13.75.Cs, 21.30.+y, 29.25.Fb Meson-exchange models of the nucleon-nucleon (AW) interaction above the pion threshold rely on detailed information about the strongly coupled inelastic channels which must be treated coherently with the elastic interaction. Information on pion production in the NN system is also required in models of pion production or absorption in nuclei. Customarily, the partial waves in the exit channel of NN-* NNK reactions are labeled by Ll, where L is the angular momentum of the nucleon pair and / is the angular momentum of the pion with respect to the nucleon pair. l Within 100 MeV of threshold, because of the short range of the interaction, only Ss, Sp, Ps, and Pp final states contribute significantly; within 25 MeV the Ss configuration should dominate. In addition, the Sp final state is forbidden in the pp-* ppn° reaction.In the pp-^ppK° reaction, the normally dominant pion production via an intermediate A7V system is suppressed, since the N and the A cannot be in a relative S state. The rescattering contribution is also small because the dominant isovector part of low-energy nN scattering cannot contribute. Thus, near threshold, the pp-*ppn° reaction is dominated by the direct-production Born term. 2 The energy dependence of the cross section is customarily expressed in terms of n, the largest possible center-of-mass pion momentum (with nucleons at rest relative to each other) divided by the pion mass. Based on phase-space arguments, the assumption of r/ o)-This should greatly simplify the theoretical interpretation of the data. The experiment described here is the first to cover this energy range. Previous experiments were hampered by the fact that the cross section (due to the suppressed resonant production) is small and competes with background caused by nuclei other than hydrogen in the path of the beam. Because of the properties of the novel experimental environment described below, it becomes feasible to measure the four-momenta of both outgoing protons, making it possible to comple...

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Using the strong selectivity of the A(p,~)A + 1 reaction for population of high-spin, two-particle one-hole final states, we have located and identified several candidates for high-spin states in the sd-shell nuclei Na, Al, Si, 'P, 'OS, and 'S. The spin assignments are based on both the strong population of the states and the stretched-state signature of the analyzing power angular distributions.

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The NPDGamma collaboration reports results from the first phase of a measurement of the parity violating up-down asymmetry Aγ with respect to the neutron spin direction of γ-rays emitted in the reaction n + p → d + γ using the capture of polarized cold neutrons on the protons in a liquid parahydrogen target. One expects parity-odd effects in the hadronic weak interaction (HWI) between nucleons to be induced by the weak interaction between quarks. Aγ in n + p → d + γ is dominated by a ∆I = 1, 3 S1 − 3 P1 parity-odd transition amplitude in the n-p system. The first phase of the measurement was completed at the Los Alamos Neutron Science Center spallation source (LANSCE) with the result Aγ = (−1.2 ± 2.1 stat. ± 0.2 sys.) × 10 −7 . We also report the first measurement of an upper limit for the parity allowed left right asymmetry in this reaction, with the result Aγ,LR = (−1.8 ± 1.9 stat. ± 0.2 sys.) × 10 −7 . In this paper we give a detailed report on the theoretical background, experimental setup, measurements, extraction of the parity-odd and parity-allowed asymmetries, analysis of potential systematic effects, and the LANSCE results. The asymmetry has an estimated size of 5 × 10 −8 and the aim of the NPDGamma collaboration is to measure it to 1 × 10 −8 . The second phase of the measurement will be performed at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory.