On the $\mth{Q}$-value of the tritium $\mth{\beta}$-decay

Sz. Nagy; T. Fritioff; M. Björkhage; I. Bergström; R. Schuch

doi:doi:10.1209/epl/i2005-10559-2

Europhys. Lett., 74 (3), pp. 404-410 (2006)
DOI: 10.1209/epl/i2005-10559-2

On the $\mth{Q}$ -value of the tritium $\mth{\beta}$ -decay

Sz. Nagy¹, T. Fritioff¹, M. Björkhage², I. Bergström² and R. Schuch¹

¹ Atomic Physics, AlbaNova, Stockholm University - S-106 91 Stockholm, Sweden
² Manne Siegbahn Laboratory (MSL) - Frescativägen 24, S-104 05 Stockholm, Sweden

Tomas.Fritioff@physto.se

received 17 November 2005; accepted in final form 7 March 2006
published online 7 April 2006

Abstract
We report here the atomic masses of ³H and ³He determined by using the Penning trap mass spectrometer SMILETRAP. The measurements are based on cyclotron frequency determinations of ³H¹⁺ and ³He¹⁺ using H₂⁺ ions as mass reference. The mass values for ³H and ³He are 3.016 049 278 7(25) $\un{u}$ and 3.016 029 321 7(26) $\un{u}$ , respectively. From these masses a new Q-value of the tritium $\beta$ -decay was derived resulting in 18.589 8(12) $\un{keV}$ , being the most accurate value at present. The Q-value of the tritium $\beta$ -decay is related to the possible rest mass of the electron antineutrino.

PACS
07.75.+h - Mass spectrometers.
27.10.+h - Properties of specific nuclei listed by mass ranges: $A \le 5$ .
32.10.Bi - Atomic masses, mass spectra, abundances, and isotopes.

© EDP Sciences 2006

On the -value of the tritium -decay

On the $\mth{Q}$ -value of the tritium $\mth{\beta}$ -decay