Article
Polarization effects in the 2H(3He, tp)p reaction at E = 33 MeV
School of Physics and Space Research, University of Birmingham, UK
Nuclear Physics A (Impact Factor: 2.2). 04/1991; 526(1):4558. DOI: 10.1016/03759474(91)90297J ABSTRACT
Tripledifferential cross sections and vector analyzing powers have been measured for the 2H(3He, tp)p reaction at EHe = 32.5 MeV. Data are presented for ten pairs of lab angles in the range θt = 15°–30°, θp = 20°–55°, most of which correspond to the kinematic region in which the quasifree 3He + n → t + p reaction with the unobserved proton as spectator is expected to be the dominant mechanism. In addition to the usual QFR maximum, most of the energysharing distributions of cross section exhibit a smaller maximum at lower energy along the kinematic locus in the Et, Ep plane. The analyzing power is generally negative in the vicinity of the QFR peak, but exhibits a maximum in the region between the two peaks in the cross section. This behavior is reproduced by distortedwave impulseapproximation calculations which include coherently amplitudes corresponding to the cases in which each of the two protons in the final state are the spectator. The best agreement with the data is obtained when the radial integrals are cut off at a maximum radius of ~ 15 fm. The predicted analyzing powers show little sensitivity to the parameters of the twobody reaction, but rather depend almost entirely on the spinorbit terms in the distorting potentials, a behavior which is similar to that observed in nucleontransfer reactions involving a transferred orbital angular momentum of zero.

Article: Spin polarization effects in the 3He(d, 3He p)n and the 3He(d, t p)p reactions at Ed = 17 MeV
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ABSTRACT: Tripledifferential cross sections and vector analyzing powers were measured for the 3He(d, 3He p)n and the 3He(d, t p)p reactions at Ed = 17 MeV. Data are presented for four pairs of coplanar detection angles for the 3He/triton and proton where quasifree scattering (QFS) or quasifree reaction (QFR) processes are expected to be dominant, and for five sets of angles where the kinematics favor the nucleonnucleon finalstate interaction (NN FSI). Tensoranalyzingpower measurements, T20 and T22, are also presented for two sets of angles. For the angle pairs where the QFS/QFR mechanism is important, the data are compared with the predictions of PWIA and DWIA calculations. While both calculations are only partly successful in describing the shapes of the quasifree peaks, the DWIA better predicts their magnitudes. The vector analyzing powers (VAP) in the quasifree region are at best only qualitatively reproduced by both calculations for the QFS, while for the QFR there is quantitative agreement between both calculations and the data only in the energy region near the center of the QFR maximum. Data obtained for the angle pairs where the NN FSI is present are compared to the predictions of a simple twostep model. The reaction is assumed to proceed by pickup of a nucleon from the 3He by the deuteron, followed by breakup of the recoil dinucleon system. These calculations describe the shapes and magnitudes of the NN FSI peaks reasonably well. The VAP predictions are for the most part also consistent with the twostep assumption. In all of the data, strong contributions are present from nucleontrion FSI corresponding to the 0 and 2 resonances in 4He at Ex = 21.1 and 22.1 MeV, respectively. 
Article: Breakup of 3He with 59.6 MeV vectorpolarized deuterons at dp quasifreescattering conditions
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ABSTRACT: The 3He breakup reaction has been studied with 59.6 MeV vectorpolarized deuterons at dp quasifreescattering (QFS) conditions. In the coincidence energy spectra, large bumps corresponding to the QFS were observed. The calculation in the simple planewave impulse approximation (PWIA) qualitatively reproduces the energy spectra, but for the absolute cross sections, the ratio of the experimental values to the calculated values in the PWIA is about 0.27. As for the analyzing powers, the experimental values are greatly reduced as compared with the dp elasticscattering data. The multiplescattering effect has been investigated by a calculation taking account of the effects of doublescattering terms on the cross sections and the analyzing powers.  [Show abstract] [Hide abstract]
ABSTRACT: A review of the evidence on the properties of the nuclei A=5, 6 and 7, with emphasis on material leading to information about the structure of the A=5, 6, 7 systems. (References closed 23 August 2001.)
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