Roy Middleton

Level structure of 37Ar and 41Ar

Abstract Argon gas targets containing 99.6% 40 Ar and 99.1% 36 Ar, respectively, were bombarded with 11 MeV deuterons. The emitted protons were magnetically analysed and recorded on nuclear emulsions. Measurements were made of 122 proton groups corresponding to levels in 41 Ar below 8.3 MeV excitation energy and of 76 proton groups corresponding to levels in 37 Ar below 9.1 MeV excitation energy.

The (1f72)2 states in 34S

Abstract A distorted wave analysis of the 32 S(t,p) 34 S reaction reveals that the 0 + state at 5.86 MeV, the 2 + state at 7.80 MeV and the 4 + state at 8.42 MeV are the principal components of the (1 f 7 2 2 , T = 1 multiplet.

Study of the reaction 12C + 13C → α + 21Ne

Abstract The reaction 12 C + 13 C → α + 21 Ne has been investigated at a c.m. bombarding energy of 14.5 MeV using beams of both 12 C and 13 C. The α-particle reaction products were recorded using a multiple-angle spectrograph. Seventy-six levels were observed below 12.56 MeV in 21 Ne; 28 levels from 9.42 to 12.56 MeV are reported for the first time. The data are consistent with a compound-nucleus reaction mechanism.

Study of the reaction 12C + 14N → α + 22Na

Abstract The 12 C( 14 N, α) 22 Na reaction has been investigated at 14 N bombarding energies of 30.3, 35.0, 40.0 and 45.5 MeV, and the 14 N( 12 C, α) 22 Na reaction has been investigated at a 12 C bombarding energy of 39.3 MeV. The α-particle reaction products were recorded using a multiple-gap spectrograph. One hundred eighty-five levels below 17.86 MeV have now been observed in 22 Na, many of them for the first time. Though some “resonance”-like behavior is observed, the overall results are consistent with a compound-nucleus reaction mechanism.

The 14N(τ, p)16O(g.s.) reaction between 7.9 and 18.0 MeV

Abstract Angular distributions of ground state protons from the 14 N(τ, p) 16 O reaction have been measured in the (laboratory) angular range 0°–160° at E ( τ ) = 7.96, 8.60, 9.80 and 10.63 MeV and in the range 7.5°–157.5° at E ( τ ) = 12.0, 14.0, 15.0 and 18.0 MeV. It is concluded that compound nucleus formation, or an intermediate process, dominates the reaction mechanism over most of the energy range investigated. At the higher energies, two-particle distorted-wave calculations have been performed, using standard optical-model parameters. Fits are reasonable only at forward angles, where the data indicate a dominant L = 2 contribution to the angular distribution. These fits favor the Cohen-Kurath description of the 14 N and 16 O ground states over that of Zuker, Buck and McGrory.