Q value of ;{115}In --> ;{115}sn(3/2;{+}): the lowest known energy beta decay

Brianna J Mount; Matthew Redshaw; Edmund G Myers

doi:10.1103/PhysRevLett.103.122502

Q value of ;{115}In --> ;{115}sn(3/2;{+}): the lowest known energy beta decay

Phys Rev Lett. 2009 Sep 18;103(12):122502. doi: 10.1103/PhysRevLett.103.122502. Epub 2009 Sep 16.

Authors

Brianna J Mount¹, Matthew Redshaw, Edmund G Myers

Affiliation

¹ Department of Physics, Florida State University, Tallahassee, Florida 32306-4350, USA.

PMID: 19792427
DOI: 10.1103/PhysRevLett.103.122502

Abstract

Using precision, cryogenic, Penning-trap mass spectrometry we have measured the atomic mass difference M[;{115}In]-M[;{115}Sn] to be 497.489(10) keV/c;{2}. Combined with the energy of the 3/2;{+} first excited state of ;{115}Sn [J. Blachot, Nuclear Data Sheets 104, 967 (2005)10.1016/j.nds.2005.03.003], the Q value of the ;{115}In(9/2;{+}) --> ;{115}Sn(3/2;{+}) beta decay is determined to be 155(24) eV. This confirms the inference of Cattadori [Nucl. Phys. A 748, 333 (2005)10.1016/j.nuclphysa.2004.10.025] that this small branching-ratio beta decay has the lowest-known Q value. We also report improved values of the individual atomic masses: M[;{115}In] = 114.903 878 774(16) u and M[;{115}Sn] = 114.903 344 697(17) u.