We propose a -decay experiment based on a sample of ultracold atomic tritium. These initial conditions enable detection of the helium ion in coincidence with the . We construct a two-dimensional fit incorporating both the shape of the -spectrum and the direct reconstruction of the neutrino mass peak....

Brownian motion of particles impacts many branches of science. We report on the Brownian motion of micronsized beads of glass held in air in an optical tweezer, over a wide range of pressures, and measure the instantaneous velocity of a Brownian particle. Our results provide direct verification of the...