Fig. 4.

Monte Carlo estimate of HOLMES neutrino mass statistical sensitivity for $N_{ev}$ $=3\times {10}^{13}$ (lower curve) or ${10}^{10}$ (upper curve) and with $f_{pp}$ $=3\times {10}^{-4}$, $\mathrm{\Delta }E$ ${}_{\mathrm{FWHM}}$ $=1$ eV, and no background