Electron emission in the deuteron-deuteron reaction supporting existence of the single-particle threshold resonance in 4 He has been observed for the first time. The measured electron energy spectrum and the electron-proton branching ratio agree very well with the assumed electron-positron pair creation decay of the 0+ resonance state to the ground state and the detailed Monte Carlo simulations of the experimental energy spectrum.
@article{arxiv.2305.17101,
title = {First observation of electron emission from the DD threshold resonance},
author = {K. Czerski and R. Dubey and M. Kaczmarski and A. Kowalska and N. Targosz-Sleczka and G. Das Haridas and M. Valat},
journal= {arXiv preprint arXiv:2305.17101},
year = {2024}
}