Atomic Masses of Tritium and Helium-3
POSTER
Abstract
By measuring the cyclotron frequency ratios of $^{3}$He$^{+}$ to HD$^{+}$ and T$^{+}$ to HD$^{+}$, and using HD$^{+}$ as a mass reference, we obtain new atomic masses for $^{3}$He and T. Our results are M[$^{3}$He] $=$ 3.016 029 322 43(19) u and M[T] $=$ 3.016 049 281 78(19) u, where the uncertainty includes an uncertainty of 0.12 nu in the mass reference. Allowing for cancellation of common systematic errors, we find the Q-value for tritium beta-decay to be (M[T] -- M[$^{3}$He])$c^{2} = $ 18 592.01(7) eV. This allows an improved test of systematics in measurements of tritium beta-decay that set limits on neutrino mass.
*Support by the NSF under PHY-0968889 and by the NIST PMG program.