European Physical Journal A vol:23 issue:2 pages:243-247
A new measurement of the Fr-200 alpha-decay half-life, with improved accuracy compared to previous measurements, has been carried out at the Isolde-CERN on-line mass separator. A half-life of 49(4) ms has been obtained, which is substantially different from earlier literature values. For the At-196 daughter decay, a half-life of 389(54) ms and an alpha branching ratio b(alpha) = 94(5)% were measured. In addition, the half-lives of Fr-201,Fr-203,Fr-205 and At-197,At-199 are reported.