Detailed studies of $$^{100}$$ 100 Mo two-neutrino double beta decay in NEMO-3

The full data set of the NEMO-3 experiment has been used to measure the half-life of the two-neutrino double beta decayof \(^{100}\)Mo to the ground state of \(^{100}\)Ru, \(T_{1/2} = \left[ 6.81 \pm 0.01\,\left( \text{ stat }\right) ^{+0.38}_{-0.40}\,\left( \text{ syst }\right) \right] \times 10^{18}\) year. The two-electron energy sum, single electron energy spectra and distribution of the angle between the electrons are presented with an unprecedented statistics of \(5\times 10^5\) events and a signal-to-background ratio of \(\sim \) 80. Clear evidence for the Single State Dominance model is found for this nuclear transition. Limits on Majoronemitting neutrinoless double beta decaymodes with spectral indices of \(\mathrm{n}=2,3,7\), as well as constraints on Lorentz invariance violation and on the bosonic neutrino contribution to the two-neutrino double beta decaymode are obtained.