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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Search for long-lived heavy neutral leptons and Higgs portal scalars decaying in the MicroBooNE detector
AU - MicroBooNE Collaboration
AU - Abratenko, P.
AU - Anthony, J.
AU - Arellano, L.
AU - Asaadi, J.
AU - Ashkenazi, A.
AU - Balasubramanian, S.
AU - Baller, B.
AU - Barnes, C.
AU - Barr, G.
AU - Barrow, J.
AU - Basque, V.
AU - Bathe-Peters, L.
AU - Rodrigues, O. Benevides
AU - Berkman, S.
AU - Bhanderi, A.
AU - Bhattacharya, M.
AU - Bishai, M.
AU - Blake, A.
AU - Bogart, B.
AU - Bolton, T.
AU - Book, J. Y.
AU - Camilleri, L.
AU - Caratelli, D.
AU - Terrazas, I. Caro
AU - Cavanna, F.
AU - Cerati, G.
AU - Chen, Y.
AU - Conrad, J. M.
AU - Convery, M.
AU - Cooper-Troendle, L.
AU - Crespo-Anadon, J. I.
AU - Tutto, M. Del
AU - Dennis, S. R.
AU - Detje, P.
AU - Devitt, A.
AU - Diurba, R.
AU - Dorrill, R.
AU - Duffy, K.
AU - Dytman, S.
AU - Eberly, B.
AU - Ereditato, A.
AU - Evans, J. J.
AU - Fine, R.
AU - Finnerud, O. G.
AU - Fleming, B. T.
AU - Foppiani, N.
AU - Nowak, J.
AU - Patel, N.
AU - Thorpe, C.
PY - 2022/11/28
Y1 - 2022/11/28
N2 - We present a search for long-lived Higgs portal scalars (HPS) and heavy neutral leptons (HNL) decaying in the MicroBooNE liquid-argon time projection chamber. The measurement is performed using data collected synchronously with the neutrino beam from Fermilab's Main Injector with a total exposure corresponding to 7.01×1020 protons on target. We set upper limits at the 90% confidence level on the mixing parameter |Uμ4|2 ranging from |Uμ4|2<12.9×10-8 for Majorana HNLs with a mass of mHNL=246 MeV to |Uμ4|2<0.92×10-8 for mHNL=385 MeV, assuming |Ue4|2=|Uτ4|2=0 and HNL decays into μ±π pairs. These limits on |Uμ4|2 represent an order of magnitude improvement in sensitivity compared to the previous MicroBooNE result. We also constrain the scalar-Higgs mixing angle θ by searching for HPS decays into μ+μ- final states, excluding a contour in the parameter space with lower bounds of θ2<31.3×10-9 for mHPS=212 GeV and θ2<1.09×10-9 for mHPS=275 GeV. These are the first constraints on the scalar-Higgs mixing angle θ from a dedicated experimental search in this mass range.
AB - We present a search for long-lived Higgs portal scalars (HPS) and heavy neutral leptons (HNL) decaying in the MicroBooNE liquid-argon time projection chamber. The measurement is performed using data collected synchronously with the neutrino beam from Fermilab's Main Injector with a total exposure corresponding to 7.01×1020 protons on target. We set upper limits at the 90% confidence level on the mixing parameter |Uμ4|2 ranging from |Uμ4|2<12.9×10-8 for Majorana HNLs with a mass of mHNL=246 MeV to |Uμ4|2<0.92×10-8 for mHNL=385 MeV, assuming |Ue4|2=|Uτ4|2=0 and HNL decays into μ±π pairs. These limits on |Uμ4|2 represent an order of magnitude improvement in sensitivity compared to the previous MicroBooNE result. We also constrain the scalar-Higgs mixing angle θ by searching for HPS decays into μ+μ- final states, excluding a contour in the parameter space with lower bounds of θ2<31.3×10-9 for mHPS=212 GeV and θ2<1.09×10-9 for mHPS=275 GeV. These are the first constraints on the scalar-Higgs mixing angle θ from a dedicated experimental search in this mass range.
KW - hep-ex
U2 - 10.1103/PhysRevD.106.092006
DO - 10.1103/PhysRevD.106.092006
M3 - Journal article
VL - 106
JO - Physical Review D
JF - Physical Review D
SN - 1550-7998
IS - 9
M1 - 092006
ER -