Extending the reach of leptophilic boson searches at DUNE and MiniBooNE with bremsstrahlung and resonant production

New gauge bosons coupling to leptons are simple and well-motivated extensions of the Standard Model. We study the sensitivity to gauged L-mu- L-e, L-e - L-tau and L-mu- L-tau both with the existing beam dump mode data of MiniBooNE and with the DUNE near detector. We find that including bremsstrahlung and resonant production of Z' which decays to e(+/-) and mu(+/-) final states leads to a significant improvement in existing bounds, especially for L-mu- L-e and L-e - L-tau for DUNE while competitive constraints can be achieved with the existing data from the MiniBooNE's beam dump run.