The effects of finite range and channel coupling in the reaction
Abstract
Comparisons of exact finite-range (EFR) DWBA calculations and zero-range (ZR) calculations are presented for the cross sections and analysing powers of the reaction to the ground state (), states. The data for the states are quite well fitted and show the characteristic j-dependence of the analysing powers. Only small differences between the EFR and ZR calculations are seen. The analysing power data for the state are poorly fitted by the EFR or ZR calculations but better agreement is obtained when the coupling to other levels is included in a coupled channel Born approximation (CCBA) calculation.
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Nuclear Data Sheets for A = 31
2013, Nuclear Data SheetsNuclear spectroscopic information for the known nuclides of mass 31 (F, Ne, Na, Mg, Al, Si, P, S, Cl, Ar) has been evaluated. A useful source of many of the Adopted Levels for 31P and 31S is presented in Endtʼs evaluations (1998En04,1990En08,1978En02,1973EnVA), however all the adopted properties of levels and gamma rays have been re-evaluated in this work. The data sets for reactions and decays, including all available gamma–ray data, are based mostly on the original literature.
The 31Mg nuclide is a prime candidate for the study of ‘island-of-inversion’ as its ground state and first excited state can only be explained by intruder orbitals in a deformed shell-model approach. 31S is of importance in astrophysics rp-process as a possible ‘bottleneck’ nuclide. There are no data available for excited states in 31F, 31Ne and 31Ar. No gamma transitions are known in 31Cl. For 31Na, only one excited state is known. The radioactive decay characteristics of 31F and 31Ne isotopes have not yet been investigated. The 31S and 31Mg nuclei are currently being pursued intensively by various experimental groups, including recent work by Nuclear Astrophysics group at McMaster, the results of which will soon become available.
One-nucleon pickup reactions on <sup>32</sup>S: Experimental results and shell-model calculations
1999, Nuclear Physics AThe 32S(d,3He)31P and reactions have been investigated at incident energies of Ed = 27 MeV and E3He = 25 MeV. The experimental values of excitation energies (0 ⩽ Ex(MeV) ⩽ 8) have been compared with the predictions of a complete sd-shell space, shell-model calculation. Spectroscopic factors obtained for 22 levels of 31S through the DWBA analysis of the experimental angular distributions have also been compared with the shell-model predictions. In order to reconcile the experimental and shell-model predicted values of the spectroscopic factors, the geometrical parameters of the spin-orbit part of the transferred nucleon potential are required to be smaller than those of the central part as it was previously observed in studies of the one-proton (3He,d) stripping reaction. The experimental fragmentation of the and strengths is correctly reproduced by the shell-model calculations. Twenty pairs of levels were identified as mirror states in the 31S and 31P nuclei and the ambiguities concerning the Jπ-values of eleven 31S levels could be removed.
Spectroscopic factors from one-proton stripping reactions on sd-shell nuclei: experimental measurements and shell-model calculations
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Energy levels of A = 21-44 nuclei (VII)
1990, Nuclear Physics, Section AThe experimentally determined properties of A = 21–44 nuclides are complied and evaluated with special emphasis on nuclear spectroscopy.
Separate tables for each of the nuclides reviewed present the available information about the following properties (in this order):
- •
- excitation energies Ex,
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- γ-ray branching ratios b(γ),
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- γ-ray mixing ratios σ,
- •
- lifetimes γm or widths Λ,
- •
- neutron, proton, or α-particle resonances,
- •
- partial widths,
- •
- single-nucleon transfer reactions,
- •
- beta-decay,
- •
- arguments for spin and parity (Jπ) and isospin (T) assignments.
For each nuclide a master table summarizing the “best” or adopted values for Ex, Jπ; T and τm or Λ precedes the auxiliary tables listed above.
The review of each A-chain concludes with a discussion of isospin multiplets.
Figures are presented of the level schemes of all nuclei and, for each A-chain, an overview of the relative energies of the ground states and lowest analogue states of all nuclei in the chain.
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Nearside-farside analysis of elastic scattering of polarized <sup>3</sup>He
1987, Nuclear Physics, Section AAn exact decomposition of the scattering amplitudes into the nearside and farside components has been performed for the elastic scattering of 33 MeV 3He particles by nuclei. Calculations have been carried out for 40Ca, 54Fe, 89Y, 90,91Zr, 207,208Pb and 209Bi and compared with the available cross section and polarization data. In particular the behaviour of the vector analysing powers is examined. Calculations of the interference between the nearside and farside components demonstrate that the interference plays a significant role in certain mass/energy regions. Regions where the scattering is dominated by the nearside component are discussed.
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Present address: Department of Physics, University of Birmingham, England.