Cosmic Shielding Studies at MicroBooNE

UNSPECIFIED (2016) Cosmic Shielding Studies at MicroBooNE. Other. UNSPECIFIED.

Abstract

MicroBooNE, a 89 ton active volume liquid argon time projection chamber (LArTPC) located on the Fermilab’s Booster Neutrino Beamline, is designed to both probe neutrino physics phenomena, and further the development of LArTPC detector technology and event reconstruction. Since MicroBooNE is located only a few meters below the ground level, without significant shielding, a large flux of cosmic rays are expected to enter the detector volume. We present detailed simulation studies performed in order to quantify cosmogenic event rates in MicroBooNE. One of the most effective ways to reduce the cosmic air shower background is to use a high-density shielding material a few meters above the detector to block or attenuate the incoming cosmic particles. The effect of such an overburden on MicroBooNE backgrounds and event rates is explored and quantified using detailed simulation studies. In particular, the effect of a 3 m concrete overburden on these backgrounds is studied in detail. Special focus is given to cosmogenic electromagnetic showers that can fake an electron-like or photon-like event and pose a serious challenge to studies involving single e/γ searches which form a primary physics goal of MicroBooNE. We find that the addition of a 3 m concrete overburden can help significantly reduce difficult-to-control backgrounds which arise from non-muon cosmic ray primaries.