Speaker
Description
The N=Z nucleus 94Ag has intrigued physicists for decades thanks to its unique decay modes, long-living isomeric states, and structure. Most notably, the existence of an elusive two-proton decay channel in its spin 21+ isomeric state has been a subject of debate since its first reports in 2006 [1]. Subsequent investigations of 94Ag have not found evidence of two-proton emission, although other decay channels, such as the one-proton emission, have been reported [2]. This has raised interest to study further the feasibility of the two-proton emission of 94Ag.
Comparing spectroscopic data with atomic mass measurements points to a discrepancy of 1.4 MeV in the 21+ state energy, suggesting that the two-proton decay is energetically forbidden [3]. A direct mass measurement of the 21+ state is required to impose constraints to the possible two-proton emission channels.
The masses of the isomeric states of 94Ag have been measured for the first time, employing a combination of a hot cavity catcher laser ion source [4] and a Multi-Reflection Time-of-Flight Mass-Separator (MR-ToF-MS) at the Ion Guide Isotope Separator On-Line (IGISOL) - facility. In this contribution I will present an overview of the experiment and the masses of the 94Ag states.
References
[1] I. Mukha et al. Proton–proton correlations observed in two-proton radioactivity of 94Ag. Nature, 439:298–302, 2006
[2] J. Cerny, et al. Reinvestigation of the direct two-proton decay of the long-lived isomer 94Agm [0.4 s, 6.7 MeV, (21+)]. Physical Review Letters, 103:152502, 2009.
[3] A. Kankainen, et al. Mass measurements and implications for the energy of the high-spin isomer in 94Ag. Physical Review Letters, 101:142503, 2008.
[4] M. Reponen et al. An inductively heated hot cavity catcher laser ion source. Review of Scientific Instruments 86:123501, 2015.
