Prompt and delayed spectroscopy of 199At
Jakobsson, U., Uusitalo, J., Juutinen, S., Leino, M., Nieminen, P., Andgren, K., . . . Sorri, J. (2010). Prompt and delayed spectroscopy of 199At. Physical Review C, 82 (4), 044302. doi:10.1103/PhysRevC.82.044302
Published inPhysical Review C
© 2016 American Physical Society
The neutron-deficient nucleus At199 has been studied through γ-ray and electron spectroscopy, using the recoil-decay tagging technique. Two experiments were conducted, using a gas-filled recoil separator with a focal-plane spectrometer alone and together with a germanium-detector array at the target position. The resulting level scheme for At199 includes a new isomer with a half-life of 0.80(5) μs and a spin and parity of (29/2+). The 13/2+ isomer, which de-excites via an M2 transition to the 9/2− ground state, was measured to have a half-life of 70(20) ns. Our earlier version of the level scheme for At197 has been updated as well.