First g factor measurement using a radioactive Kr-76 beam

摘要

The g factor of the first 2(+) state of radioactive Kr-76 (T-1/2 = 14.8 h) has been measured, extending the systematics of the previously measured stable Kr-78,Kr-80,Kr-82,Kr-84,Kr-86 isotopes. The measurement was performed with a radioactive Kr-76 ion beam applying projectile Coulomb excitation in inverse kinematics combined with the transient magnetic field technique. The Kr-76 beam was produced and accelerated in batch mode (re-cyclotron method) at the Lawrence Berkeley National Laboratory 88-Inch Cyclotron. A total of three production and acceleration cycles yielded six hours of beam on target with peak rates of 10(8) particles/s. About 5.6 x 10(4) particle-gamma coincidence events were recorded. The g factor g(Kr-76; 2(1)(+)) = +0.37(11) was obtained by direct comparison to the known g(Kr-78; 2(1)(+)) value re-measured immediately after the Kr-76 runs with the same setup and under almost identical kinematic conditions. (C) 2004 Elsevier B.V. All rights reserved.