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  • Open Access

Ultraheavy diquark decaying into vectorlike quarks at the LHC

Ioana Duminica1,2, Calin Alexa1, Ioan M. Dinu1, Bogdan A. Dobrescu3, and Matei-Stefan Filip1,2

  • 1Particle Physics Department, IFIN-HH, Măgurele, IF 077125, Romania
  • 2Faculty of Physics, University of Bucharest, Măgurele, IF 077125, Romania
  • 3Particle Theory Department, Fermilab, Batavia, Illinois 60510, USA

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Phys. Rev. D 111, 115025 – Published 24 June, 2025

DOI: https://doi.org/10.1103/hxll-41ly

Abstract

We explore the discovery potential of ultraheavy (7–8.5  TeV) diquark scalars (Suu) produced in the collision of two up quarks at the LHC. Assuming that the diquark scalar decays into two vectorlike quarks of mass around 2 TeV, each of them decaying into a W+ boson and a b quark, we focus on the fully hadronic final state. We present a signal-from-background separation study based on a discriminator built with machine learning techniques. For this six-jet final state and a luminosity of 3000  fb−1, we estimate that a diquark scalar of mass near 8 TeV may be discovered or ruled out even when its coupling to up quarks is as low as 0.2.

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Phys. Rev. D 111, 115025– Published 24 June, 2025
  • Received 27 March 2025
  • Accepted 19 May 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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