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Title: Measurement of a complete set of analyzing powers and cross section of the kinematically complete breakup reaction sup 4 He( rvec d , p. alpha. ) n at 7. 0 MeV and the isospin-forbidden d sup *

Journal Article · · Physical Review, C (Nuclear Physics); (United States)
; ; ; ; ; ;  [1];  [2]
  1. Institut fuer Kernphysik, Universitaet Koeln, D-5000 Koeln 41 (Germany)
  2. Central Research Institute for Physics, H-1525, Budapest 114 (Hungary)

The breakup reaction {sup 4}He({ital {rvec d}},{ital p}{alpha}){ital n} at {ital E}{sub {ital d}}=7.0 MeV has been investigated in a kinematically complete experiment with vector and tensor polarized deuterons in a kinematical situation with zero relative energy of the two outgoing nucleons, a preferred situation to show effects from the singlet deuteron {ital d}{sup *} and therefore isospin breaking. A complete set of analyzing powers, {ital A}{sub {ital y}}, {ital A}{sub {ital y}{ital y}}, {ital A}{sub {ital x}{ital z}}, and {ital A}{sub {ital z}{ital z}} in addition to the differential breakup cross section, {ital d}{sup 3}{sigma}/{ital d}{Omega}{sub 3}{ital d}{Omega}{sub 4}{ital dS} has been measured. The data are compared to new Faddeev calculations including an approximate (cutoff) Coulomb potential allowing for the {ital d}{sup *} production and also {ital D}-wave {alpha}-{ital N} interactions. Good agreement is found for the polarization observables and the shape of the cross section which, however, disagrees in absolute magnitude. Both the inclusion of the {ital d}{sup *} and of {ital D} waves seem necessary for a good description of all data and for the interpretation of a small excursion in some observables in the {ital n}-{ital p} final-state interaction region as a manifestation of the isospin-forbidden {ital d}{sup *}.

OSTI ID:
7035095
Journal Information:
Physical Review, C (Nuclear Physics); (United States), Vol. 45:6; ISSN 0556-2813
Country of Publication:
United States
Language:
English