Excited-state transition-rate measurements in C-18
Artikel i vetenskaplig tidskrift, 2012
Excited states in C-18 were populated by the one-proton knockout reaction of an intermediate energy radioactive N-19 beam. The lifetime of the first 2(+) state was measured with the Koln/NSCL plunger via the recoil distance method to be tau (2(1)(+)) = 22.4 +/- 0.9(stat)(-2.2)(+3.3)(syst) ps, which corresponds to a reduced quadrupole transition strength of B(E2; 2(1)(+) -> 0(1)(+)) = 3.64(-0.14)(+ 0.15)(stat)(-0.47)(+0.40)(syst) e(2)fm(4). In addition, an upper limit on the lifetime of a higher-lying state feeding the 2(1)(+) state was measured to be tau < 4.6 ps. The results are compared to large-scale ab initio no-core shell model calculations using two accurate nucleon-nucleon interactions and the importance-truncation scheme. The comparison provides strong evidence that the inclusion of three-body forces is needed to describe the low-lying excited-state properties of this A = 18 system.
neutrons
beams
nuclear shell-model
lifetime measurements
Författare
P. Voss
T. Baugher
D. Bazin
R. M. Clark
H. L. Crawford
A. Dewald
P. Fallon
A. Gade
G. F. Grinyer
H. Iwasaki
A. O. Macchiavelli
S. McDaniel
D. Miller
M. Petri
A. Ratkiewicz
W. Rother
K. Starosta
K. A. Walsh
D. Weisshaar
Christian Forssen
Chalmers, Teknisk fysik, Subatomär fysik
R. Roth
P. Navratil
Physical Review C - Nuclear Physics
24699985 (ISSN) 24699993 (eISSN)
Vol. 86 1 011303Ämneskategorier
Fysik
Fundament
Grundläggande vetenskaper
DOI
10.1103/PhysRevC.86.011303