Isomeric ratios have been measured for high-spin states in Po84198,200,206,208, At85208,209,210,211, Rn86210,211,212,213,214, Fr87208,211,212,213,214, Ra88210,211,212,214,215, and Ac89215 following the projectile fragmentation of a 1 AGeV 238U beam by a 9Be target at GSI Helmholtzzentrum für Schwerionenforschung. The fragments were separated in the fragment separator (FRS) and identified by means of energy loss and time-of-flight techniques. They were brought to rest at the centre of the RISING gamma-ray detector array and intensities of gamma rays emitted in the decay of isomeric states with half-lives between 100 ns and 40 μs and spin values up to 55/2ℏ were used to obtain the corresponding isomeric ratios. The data are compared to theoretical isomeric ratios calculated in the framework of the abrasion-ablation model. Large experimental enhancements are obtained for high-spin isomers in comparison to expected values.
|Titolo:||The population of metastable states as a probe of relativistic-energy fragmentation reactions|
|Settore Scientifico Disciplinare:||Settore FIS/01 - Fisica Sperimentale|
|Data di pubblicazione:||2013|
|Digital Object Identifier (DOI):||10.1016/j.physletb.2013.05.033|
|Appare nelle tipologie:||01 - Articolo su periodico|