Light particles with baryon and lepton numbers

Abstract

We consider light new particles $χ$ and $ϕ$ that carry baryon and lepton numbers. If these particles are lighter than nucleons they lead to exotic decays such as $p\to π^+ χ$ and $p\to e^+ϕ$, not yet fully constrained by dedicated searches. For $χ$ and $ϕ$ masses in the GeV range proton decays are kinematically forbidden but other decays of the forms baryon $\to$ meson$+χ$, meson $\to$ baryon$+\barχ$, and baryon $\to$ anti-lepton$+ϕ$ involving heavy initial hadrons are allowed. This opens up the possibility to search for apparent baryon number violation not just in underground experiments such as Super-Kamiokande and DUNE but also in decays of heavy hadrons in charm and B factories.