Yes — that’s exactly the decay: in tritium, one neutron converts into a proton, so the nucleus goes from 1 proton + 2 neutrons to 2 protons + 1 neutron, which makes helium-3, and the decay also emits an electron (beta particle) plus an electron antineutrino: ( ^3_1\mathrm{H} \rightarrow ^3_2\mathrm{He} + e^- + \bar{\nu}_e ) Wikipedia U.S. DOE. Your image shows the right reaction, minus the usual bar over the neutrino symbol to make clear it’s an antineutrino, not a neutrino Wikipedia. InLeo-wise, there isn’t much direct discussion of tritium specifically; the closest relevant community mention was a general weak-force/radioactive-decay explanation thread.