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Soft-unclustered-energy patterns from quirks

David Curtin1,2,*, Sascha Dreyer3,†, Max Fusté Costa3,4,‡, Sarah Heim3,4,§, Gregor Kasieczka4,∥, Louis Moureaux4,¶, David Rousso3,**, David Shih5,††, and Manuel Sommerhalder4

  • *Contact author: dcurtin@physics.utoronto.ca
  • †Contact author: sascha.dreyer@desy.de
  • ‡Contact author: max.fuste.costa@desy.de
  • §Contact author: sarah.heim@desy.de
  • ∥Contact author: gregor.kasieczka@uni-hamburg.de
  • Contact author: louis.moureaux@cern.ch
  • **Contact author: david.rousso@desy.de
  • ††Contact author: shih@physics.rutgers.edu
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Phys. Rev. D 113, 015010 – Published 9 January, 2026

DOI: https://doi.org/10.1103/g7c7-6qh2

Abstract

We propose searching for physics beyond the Standard Model in the low-transverse-momentum tracks accompanying hard-scatter events at the LHC. TeV-scale resonances connected to a dark QCD sector could be enhanced by selecting events with anomalies in the track distributions. As a benchmark, a quirk model with microscopic string lengths is developed, including a setup for event simulation. For this model, strategies are presented to enhance the sensitivity compared to inclusive resonance searches: a simple cut-based selection, a supervised search, and a model-agnostic weakly supervised anomaly search with the CATHODE method. Expected discovery potentials and exclusion limits are shown for 140  fb−1 of 13 TeV proton-proton collisions at the LHC.

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Outline

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Phys. Rev. D 113, 015010– Published 9 January, 2026
  • Received 19 June 2025
  • Accepted 25 November 2025
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3.

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