The overwhelming evidence of dark matter suggests that there could be a dark sector of particles that we have yet to discover. One of the simplest portals into the dark sector is through a dark U(1) gauge boson, called the dark photon. We propose a new mechanism for dark photon production from secondary pion Bremsstrahlung in a beam dump target. As protons scatter in the beam dump, they produce secondary charged pions. These pions take a fraction of the proton's energy and continue down the beam path, where they scatter off the target's nuclei and can radiate off a dark photon. We calculate the sensitivity of detecting a dark photon produced through this mechanism at the SeaQuest experiment. We find that we can extend the sensitivity of SeaQuest to lower values of the dark photon's kinetic coupling constant, where proton Bremsstrahlung no longer dominates.
The muon anomalous magnetic moment problem is a longstanding discrepancy between the theoretical calculation and experimental determination of this observable. In this talk, I will discuss a possible solution to it that involves adding a scalar particle that couples to muons to the standard model. I will describe a proton beam fixed-target experiment called DarkQuest at Fermilab which may be able to detect this new particle at masses below 1 GeV. Finally, I will talk about the signal and background kinematics, along with strategies for reducing the background to obtain the best possible sensitivity.