Search for Excited States inHe3

Abstract

tors for large values of angular momentum and energies close to the Coulomb barrier are strongly dependent upon the radius chosen for the nuclear surface. This dependence is reflected in our analysis and is quite pronounced for the g Q/2 state, although we do not factorize the partial width into a reduced width and a penetration factor. Similarly, the spectroscopic factors also depend weakly upon the strength of V v For the five states in 209 pb that we studied, this dependence is well described by Moore for discussions. The computer codes used were obtained by putting together codes written by T. Tamura and F. G. Perey.Uncertainties in the extracted spectroscopic factors arising from the above-mentioned dependences are much larger than those due to other optical model parameters.In conclusion, we note that the above method for extracting spectroscopic factors of the parent analog states appears very promising since the results do not depend strongly on the choice of optical-model parameters. This method can easily be modified to analyze the inelastic proton scattering through the isobaric analog resonances. It is simple to use and one retains the advantages offered by the Breit-Wigner single level formula. A method similar in spirit to the one presented has recently been reported. 9 Similar calculations are in progress for a number of other nuclei.It is a pleasure to acknowledge helpful discussions with H.A search for 3 He excited states in the reaction 3 He ip,p') 3 He* with proton bombarding energy of 30.9 MeV has been made. No inelastic peaks were observed.Since the discovery of 4 He excited states, the A = 3 nuclear system remains the only isobaric sequence in which no excited states are known to exist. In principle, knowledge of excited states in the mass-three system could directly enrich our understanding of nuclear forces. For this reason, a report by Kim et al. 1 of the observation of 3 He excited states prompted us and several other groups to re-examine the 3 He nucleus.Kim et al. 1 observed peaks in the spectrum of protons inelastically scattered from 3 He at 30.2-MeV bombarding energy. The peaks, which were observed at two laboratory angles, were interpreted as indications of 3 He states (r ^0.9 MeV) at approximately 10.2-and 12.6-MeV excitation. They reported laboratory cross sections of 2.0 and ~0.6 mb/sr, respectively, 1449

Final-state interactions

“…T h e interest was renewed when Kim et al (1966) reported several sharp levels in the reaction 3He(p, P ' ) ~H ~* , the lowest of which was thought to be the analogue to the trineutron bound state. However later work by Austin et al (1967) and Mancusi et al (1967) showed no evidence for them. The reaction 3He(3He, 3He')3He* studied by Slobodrian et al (1967 b) gave similar negative results for the existence of T = 4 and T = 8 states.…”