Search for a Higgs portal scalar decaying to electron-positron pairs in the MicroBooNE detector

Blake, A. and Devitt, D. and Nowak, J. and Thorpe, C. (2021) Search for a Higgs portal scalar decaying to electron-positron pairs in the MicroBooNE detector. Physical review letters, 127 (15): 151803. ISSN 1079-7114

Text (HiggsPortalAAM)
HiggsPortalAAM.pdf - Accepted Version
Available under License Creative Commons Attribution.
Download (362kB)

Abstract

We present a search for the decays of a neutral scalar boson produced by kaons decaying at rest, in the context of the Higgs portal model, using the MicroBooNE detector. We analyze data triggered in time with the Fermilab NuMI neutrino beam spill, with an exposure of $1.93\times10^{20}$ protons on target. We look for monoenergetic scalars that come from the direction of the NuMI hadron absorber, at a distance of 100 m from the detector, and decay to electron-positron pairs. We observe one candidate event, with a Standard Model background prediction of $1.9\pm0.8$. We set an upper limit on the scalar-Higgs mixing angle of $\theta