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

0556-2813 (ISSN) 1089-490X (eISSN)

Vol. 86

Ämneskategorier

Fysik

Fundament

Grundläggande vetenskaper

DOI

10.1103/PhysRevC.86.011303