Two-deuteron photodisintegration of 4 He at Eγ=150-250 MeV


Journal Article

We have performed a measurement of the cross section for the 4He(γ,dd) reaction with photon energies between 150 and 250 MeV. Both reaction particles were detected in coincidence. We obtained absolute cross sections at six angles and two energy bins (150-190 MeV and 190-250 MeV). A Legendre polynomial fit to the angular distribution shows a sin2 θ distribution which suggests the isospin-forbidden E1 transition. However, a transition matrix element (TME) analysis using only strictly allowed transitions shows that the angular distribution can be described by just two TMEs: E2 s- and d-wave absorption on the D state of 4He. We performed an inverse direct-capture calculation in order to determine if the D state could contribute to such a high degree to the cross section. This calculation indicates that 90% of the cross section arises from absorption on the D state but fails to reproduce the observed sin2 θ angular distribution.

Duke Authors

Cited Authors

  • Rice, BJ; Canon, RS; Wulf, EA; Weller, HR; Keeter, K; Kolb, NR; Mueller, C; Pywell, RE; Retzlaff, GA; Skopik, DM; Feldman, G

Published Date

  • January 1, 2000

Published In

Volume / Issue

  • 61 / 6

Start / End Page

  • 646121 - 646128

Electronic International Standard Serial Number (EISSN)

  • 1089-490X

International Standard Serial Number (ISSN)

  • 0556-2813

Citation Source

  • Scopus