Ms. Gai et Ca. Bertulani, E2 CONTRIBUTION TO THE B-8-]P-7 COULOMB DISSOCIATION CROSS-SECTION - COMMENT(BE), Physical review. C. Nuclear physics, 52(3), 1995, pp. 1706-1708
The E2 cross section calculated by Langanke and Shoppa for the RIKEN e
xperiment on the Coulomb dissociation of B-8 uses E2 nuclear matrix el
ement from one specific model. Other nuclear models predict a consider
ably smaller E2 cross section (by approximately a factor of 3 to 4), a
nd Langanke and Shoppa appear to assume the most optimistic scenario,
predicting a large E2 cross section. We also note that Barker has alre
ady criticized the nuclear model used by Langanke and Shoppa. A model
independent chi-square analysis of the RIKEN data suggest the best fit
for the current RIKEN data is obtained with El amplitudes only. The u
pper limit (90% confidence) on the E2 component derived from our chi-s
quare analysis is considerably smaller than that used by Langanke and
Shoppa. The model dependent analysis of Langanke and Shoppa should not
be considered as a correction to the RIKEN result, as claimed, and th
eir quoted S-17(0) is not substantiated.