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Search for magnetic monopoles with the MoEDAL prototype trapping detector in 8 TeV proton-proton collisions at the LHC

A preprint version of the article is available at arXiv.


The MoEDAL experiment is designed to search for magnetic monopoles and other highly-ionising particles produced in high-energy collisions at the LHC. The largely passive MoEDAL detector, deployed at Interaction Point 8 on the LHC ring, relies on two dedicated direct detection techniques. The first technique is based on stacks of nucleartrack detectors with surface area ~18m2, sensitive to particle ionisation exceeding a high threshold. These detectors are analysed offline by optical scanning microscopes. The second technique is based on the trapping of charged particles in an array of roughly 800 kg of aluminium samples. These samples are monitored offline for the presence of trapped magnetic charge at a remote superconducting magnetometer facility. We present here the results of a search for magnetic monopoles using a 160 kg prototype MoEDAL trapping detector exposed to 8TeV proton-proton collisions at the LHC, for an integrated luminosity of 0.75 fb–1. No magnetic charge exceeding 0:5g D (where g D is the Dirac magnetic charge) is measured in any of the exposed samples, allowing limits to be placed on monopole production in the mass range 100 GeV≤ m ≤ 3500 GeV. Model-independent cross-section limits are presented in fiducial regions of monopole energy and direction for 1g D ≤ |g| ≤ 6g D, and model-dependent cross-section limits are obtained for Drell-Yan pair production of spin-1/2 and spin-0 monopoles for 1g D ≤ |g| ≤ 4g D. Under the assumption of Drell-Yan cross sections, mass limits are derived for |g| = 2g D and |g| = 3g D for the first time at the LHC, surpassing the results from previous collider experiments.


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Correspondence to P. Mermod.

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ArXiv ePrint: 1604.06645

Associate member. (K. Bendtz, D. Milstead)

Now deceased (G. Giacomelli)

This paper is dedicated to the memory of Giorgio Giacomelli, a pioneer and leader in the quest for the Magnetic Monopole.

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The MoEDAL collaboration., Acharya, B., Alexandre, J. et al. Search for magnetic monopoles with the MoEDAL prototype trapping detector in 8 TeV proton-proton collisions at the LHC. J. High Energ. Phys. 2016, 67 (2016).

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  • Exotics
  • Hadron-Hadron scattering (experiments)
  • Particle and resonance production