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Discovering true muonium at LHCb

Xabier Cid Vidal1,*, Philip Ilten2,†, Jonathan Plews2,‡, Brian Shuve3,4,§, and Yotam Soreq5,6,∥

  • 1Instituto Galego de Fısica de Altas Enerxıas (IGFAE), Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain
  • 2School of Physics and Astronomy, University of Birmingham, Birmingham B152 2TT, United Kingdom
  • 3Harvey Mudd College, 301 Platt Boulevard, Claremont, California 91711, USA
  • 4University of California, 900 University Avenue, Riverside, California 92521, USA
  • 5Theoretical Physics Department, CERN, CH-1211 Geneva 23, Switzerland
  • 6Department of Physics, Technion, Haifa 32000, Israel

  • *xabier.cid.vidal@cern.ch
  • †philten@cern.ch
  • ‡jonathan.plews@cern.ch
  • §bshuve@g.hmc.edu
  • ∥yotam.soreq@cern.ch
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Phys. Rev. D 100, 053003 – Published 10 September, 2019

DOI: https://doi.org/10.1103/PhysRevD.100.053003

Abstract

We study the potential of the LHCb experiment to discover, for the first time, the μ+μ− true muonium bound state. We propose a search for the vector 13S1 state, TM, which kinetically mixes with the photon and dominantly decays to e+e−. We demonstrate that a search for η→γTM, TM→e+e− in a displaced vertex can exceed a significance of 5 standard deviations assuming statistical uncertainties. We present two possible searches: an inclusive search for the e+e− vertex, and an exclusive search which requires an additional photon and a reconstruction of the η mass.

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Phys. Rev. D 100, 053003– Published 10 September, 2019
  • Received 3 May 2019
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