The singlet majoron model of seesaw neutrino mass is appended by one dark Majorana fermion singlet $chi$ with $L=2$ and one dark complex scalar singlet $zeta$ with $L=1$. This simple setup allows $chi$ to obtain a small radiative mass anchored by the same heavy right-handed neutrinos, whereas the one-loop decay of the standard-model Higgs boson to $chi chi + bar{chi} bar{chi}$ provides the freeze-in mechanism for $chi$ to be the light dark matter of the Universe.
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