Eur. Phys. J. A (2003) 18: 31-37
https://doi.org/10.1140/epja/i2003-10066-6

OriginalPaper

Isomeric and ground-state decay of ²¹⁵ Bi

¹ Institute of Experimental Physics, Warsaw University, Hoza 69, PL-00681, Warsaw, Poland
² Department of Physics, Oliver Lodge Laboratory, University of Liverpool, P.O. Box 147, L697ZE, Liverpool, UK
³ Department of Physics, Accelerator Laboratory, University of Jyväskylä, FIN-40351, Jyväskylä, Finland
⁴ ISOLDE, CERN-PPE, CH-1211, Geneva 23, Switzerland
⁵ Instituut voor Kern-en Stralingsfysica, University of Leuven, Celestijnenlaan 200D, B-3001, Leuven, Belgium
⁶ Institute of Spectroscopy, Russian Academy of Sciences, 142190, Troitzk, Russia
⁷ GSI, D-64291, Darmstadt, Germany
⁸ Institut de Recherches Subatomiques et Université Louis Pasteur, F-67037, Strasbourg, France
⁹ ORNL Physics Division, TN 37830, Oak Ridge, USA
¹⁰ University of Munich, D-85748, Garching, Germany

^* e-mail: jkurpeta@mimuw.edu.pl

Abstract

A new high-spin isomer in ²¹⁵Bi, with a half-life of 36.9(6) s, has been identified at the PSB-ISOLDE on-line mass separator using the pulsed-release technique combined with the element selective RILIS source. A decay scheme of $^{215{\rm m}}$Bi was constructed and complemented with the low-spinstructure observed in $^{215{\rm g}}$Bi decay. The population of a cascade on top of the $\left( \nu g_{9/2} \right)^5_{9/2+}$ level in ²¹⁵Poprovides evidence for Gamow-Teller $\beta$-decay of the high-spin ²¹⁵Bi isomer.