The 0(g.s.)(+)-> 2(1)(+) transition in Ca-38 and isospin symmetry in A=38 nuclei - art. no. 031301

The B(E2;0(g.s.)(+) --> 2(1)(+)) value for Ca-38 has been measured via the technique of intermediate energy Coulomb excitation using a beam of radioac tive Ca-38 nuclei. The present result is used to test isospin purity in the mass 38 system by comparing the isoscalar multipole matrix element M-o ext racted from the 0(g.s.)(+)-->2(1)(+) transitions in Ca-38 and Ar-38 to the corresponding matrix element obtained from the T=1 states of the T-z=0 nucl eus K-38. A discrepancy between the two values of M-o is found, suggesting that isospin symmetry is broken in A=38 nuclei. Similar discrepancies occur for A = 34 and 42. Experiments for addressing these discrepancies are prop osed. [S0556-2813(99)50109-X].