Identification of the Neutron-Deficient Isotopes 213,214-Pa

V. Ninov, F.P. Heßberger, S. Hofmann, H. Folger, Gesellschaft für Schwerionenforschung, D-64220 Darmstadt Germany

A.G. Popeko, A.V. Yeremin, A.N. Andreyev
Flerov Laboratory of Nuclear Research, JINR, 141 980 Dubna, Russia

S. Saro
Deparment of Nuclear Physics, Comenius University, SK-84215 Bratislava, Slovakia

Abstract:

Two new neutron-deficient istopes, 213-Pa and 214-Pa were produced in complete fusion reactions of 51-V-ions with 170-Er targets at (5.2-5.6) AMeV. The assignment was based on delayed evaporation-alpha-alpha time and position coincidences. The alpha-decay energy of 213,214-Pa were measured to be E-alpha=(8236 +- 20) keV an E-alpha=(8116+-20) keV, respectively. The half-lives of 213,214-Pa were determined to be T1/2=(5.3+4.0-1.6) ms and T1/2=(5.3+-3) ms, respectively.