Tritium\char21helium-3 mass difference using the Penning trap mass spectroscopy
The atomic masses of both 3H and 3He have been measured with a Penning trap mass spectrometer that utilizes a frequency-shift detector to observe ion cyclotron resonances. Present resolution exceeds 1 part in 109 and is limited only by the stability of the magnetic field. The leading systematic shift (at â²1 part in 1010) is due to the residual quadratic B field dependence. The atomic masses have been combined to yield ÎMc2(3H-3He)=18 590.1(1.7) eV. The excellent agreement with recent results from Î² spectrometers lends strong support for new limits on the neutrinoâs rest mass.