Takao Nakashima

A Detailed Study of Low-Lying Levels of 184W by Means of the (d,p) Reaction

Targets of separated isotopes 182 W and 183 W were bombarded with a 15 MeV deuteron beam, and outgoing protons were analyzed with a broad range magnetic spectrograph and nuclear emulsion plates. Empirical single-particle cross sections were determined from the observed cross sections and angular distributions of the reactions leading to low-lying levels of 183 W. Observed cross sections and angular distributions for the levels of 184 W were compared with the cross sections which were obtained by using the above empirical single-particle cross sections and the spectroscopic factors calculated from the pairing theory. For the members of the ground state rotational band and the γ-vibrational band in 184 W excellent agreements were obtained. Reasonably good agreements were found for six higher levels below 1800 keV, if they were interpreted as the rotational members of possible two-quasiparticle states. For the first two levels of the lowest excited K =0 + band cross sections were determined.

90°-Excitation Functions for the N 14 ( d , α)C 12 Ground-State and First Excited State Reactions

Measurements of the differential excitation functions for the N/sup 14/ (d, alpha )C/sup 12/ ground-state and first excited state reactions were made at 90 deg to the incident deuteron beam, in the range of bombarding energies from 1 to 3 Mev. A deuteron beam from a Van de Graaff was used to bombard a 0.28 mg/cm/ sup 2/ thick melamine layer evaporated on a nickel foil. Alpha particles were detected with a silicon junction detector 2 mm in dia. Resuits are shown together with related results obtained by several authors. (W.D.M.)

Angular Distribution and Excitation Functions of the Be 9 ( d , p ) Be 10 Ground-State Reaction

Angular distributions and excitation functions of the Re/sup 9/(d,p)Be/ sup 10/ ground-state reaction are studied in the deuteron energy range from 1.7 to 3.0 Mev. Six angular distributions are measured at deuteron energies of 1.74, 1-97, has a forward peak characteristic of the deuteron stripping process for l/ sub n/ = 1. The yields in the backward directions, however, are predominant at the lower energies. The excitation ourve taken at the laboratory angle of 30 deg , where the forward peak occurs in the angular distribution, shows a monotone and rather fast rise with deuteron energy. On the other hand, the excitation function of the total cross section of this reaction shows a comparatively slow variation and has a broad peak at about 2.1 Mev of deuteron energy. (auth)

Differential Excitation Functions for Alpha-Particle and Proton Groups from the Deuteron Induced Reactions on F19

The reactions F¹⁹(d,p)F²⁰ and F⁹ (d, alpha )O¹⁷, leading to the ground state of F²⁰ and the ground and first excited states of O¹⁷, are studied at deuteron energies of 1.2 to 3.2 Mev. The differential excitation functions for the ground-state protons show, at various scattering angles, broad resonances at deuteron energies around 1.7 and 2.1 Mev. The alpha-particle differential excitation functions also have strong resonance- like structures. (T.F.H.)

Energy Levels of40Ca Studied by the39K(p, α0)36Ar Reaction

Resonances in the 39 K(p, α 0 ) 36 Ar reaction were investigated. In the energy region E p =3.05–4.20 MeV, 102 resonances were observed. Resonance energies, strengths and widths are reported. The angular distributions were measured at 37 resonance energies, and the analysis by the one-level formula allowed unique assignment of the spins for 17 cases. In 18 cases, two or more different spin assignments were possible. An experimental level density of 40 Ca was estimated to be ρ exp =131 MeV -1 at the excitation energy E x =11.87 MeV. By the smoothing procedure of the excitation function, a broad resonance with the width of about 400 keV was obtained at E p =3.45 MeV. An average alpha-paricle reduced width in this reaction was estimated to be about \(0.02{\times}\hbar^{2}/MR^{2}\).Resonances in the 39 K(p, α 0 ) 36 Ar reaction were investigated. In the energy region E p =3.05–4.20 MeV, 102 resonances were observed. Resonance energies, strengths and widths are reported. The angular distributions were measured at 37 resonance energies, and the analysis by the one-level formula allowed unique assignment of the spins for 17 cases. In 18 cases, two or more different spin assignments were possible. An experimental level density of 40 Ca was estimated to be ρ exp =131 MeV -1 at the excitation energy E x =11.87 MeV. By the smoothing procedure of the excitation function, a broad resonance with the width of about 400 keV was obtained at E p =3.45 MeV. An average alpha-paricle reduced width in this reaction was estimated to be about \(0.02{\times}\hbar^{2}/MR^{2}\).