Περίληψη:
We report the first evidence of breakup dominance at deep sub-barrier
energies for the proton halo nucleus B-8 on a heavy target. Angular
distribution measurements of the B-8 breakup fragment, Be-7, on lead
were performed at the TwinSol facility of the University of Notre Dame
at a beam energy of 30 MeV, 58% of the Coulomb barrier and
corresponding to a distance of closest approach of 20.5 fm. The Be-7
yield was observed in two double sided silicon strip detector telescopes
symmetrical to the radioactive beam and normalized using the B-8
Rutherford scattering. The results are in excellent agreement with
continuum discretized coupled channel calculations with a total breakup
cross section (326 +/- 84) mb. This is found to exhaust all of the total
reaction cross section for the system B-8 + (208)pb, possibly
prohibiting a fusion enhancement. This finding is expected to give more
insight to the puzzle of fusion suppression at deep sub-barrier energies
with possible major consequences on nuclear astrophysics.
Συγγραφείς:
Pakou, A.
Acosta, L.
O'Malley, P. D.
Aguilar, S. and
Aguilera, E. F.
Baines, M.
Bardayan, D.
Becchetti, F. D. and
Boomershine, Ch
Brodeur, M.
Cappuzzello, F.
Carmichael, S.
and Caves, L.
Chavez, E.
Flores-Vazquez, C.
Gula, A. and
Kolata, J. J.
Liu, B.
Marin-Lambarri, D. J.
Morales, F. F.
and Rusek, K.
Sanchez-Benitez, A. M.
Sgouros, O.
Sharma, V.
R.
Soukeras, V
Souliotis, G.
