- Physical Review Journals
All JournalsPhysics Magazine

Physical Review D

Reuse & Permissions

It is not necessary to obtain permission to reuse this article or its components as it is available under the terms of the Creative Commons Attribution 4.0 International license. This license permits unrestricted use, distribution, and reproduction in any medium, provided attribution to the author(s) and the published article's title, journal citation, and DOI are maintained. Please note that some figures may have been included with permission from other third parties. It is your responsibility to obtain the proper permission from the rights holder directly for these figures.

Export citation

Export citation

Choose format for download:

Download Citation
  • Open Access

Exploring Z′ and right-handed neutrinos in the B−L symmetric SM at the Large Hadron Collider

Kareem Ezzat1,2,*, Nidal Chamoun3,4,5,†, Shaaban Khalil2,‡, and Rhitaja Sengupta5,§

  • *Contact author: kareemezat@sci.asu.edu.eg
  • †Contact author: chamoun@uni-bonn.de
  • ‡Contact author: skhalil@zewailcity.edu.eg
  • §Contact author: rsengupt@uni-bonn.de
PDF

Phys. Rev. D 113, 015009 – Published 9 January, 2026

DOI: https://doi.org/10.1103/x6dp-4tzs

Abstract

We study the collider phenomenology of the B−L extension of the Standard Model (BLSM), focusing on the production and decay of a heavy neutral gauge boson (Z′) at the Large Hadron Collider (LHC). In this framework, the Z′ can decay into pairs of heavy right-handed neutrinos (νR), which subsequently decay into charged leptons and W bosons. These processes give rise to three distinctive final states: (i) two leptons plus four jets (2ℓ+4j), (ii) four leptons plus missing transverse energy (4ℓ+MET), and (iii) three leptons plus two jets and MET (3ℓ+2j+MET). To enhance signal sensitivity and suppress Standard Model backgrounds, we employ multivariate analysis techniques based on boosted decision trees (BDTs), as well as selection optimizations using the xgboost framework. The classifiers are trained on kinematic observables sensitive to the masses of the Z′ and νR. We demonstrate that all three final states offer significant discovery potential for both the Z′ and heavy νR at the High-Luminosity LHC. Our results highlight the testability of the BLSM at current and future collider experiments, and provide a promising avenue for probing the origin of neutrino masses and the baryon asymmetry of the Universe.

View figure in article

Physics Subject Headings (PhySH)

Article Text

References (32)

  1. Y. Fukuda et al. (Super-Kamiokande Collaboration), Evidence for oscillation of atmospheric neutrinos, Phys. Rev. Lett. 81, 1562 (1998).
  2. M. Ahn et al. (K2K Collaboration), Indications of neutrino oscillation in a 250 km long baseline experiment, Phys. Rev. Lett. 90, 041801 (2003).
  3. K. Eguchi et al. (KamLAND Collaboration), First results from KamLAND: Evidence for reactor anti-neutrino disappearance, Phys. Rev. Lett. 90, 021802 (2003).
  4. Q. Ahmad et al. (SNO Collaboration), Direct evidence for neutrino flavor transformation from neutral current interactions in the Sudbury Neutrino Observatory, Phys. Rev. Lett. 89, 011301 (2002).
  5. F. An et al. (Daya Bay Collaboration), Observation of electron-antineutrino disappearance at Daya Bay, Phys. Rev. Lett. 108, 171803 (2012).
  6. R. N. Mohapatra and R. E. Marshak, Local B-L symmetry of electroweak interactions, Majorana neutrinos and neutron oscillations, Phys. Rev. Lett. 44, 1316 (1980); 44, 1643(E) (1980).
  7. A. Papaefstathiou, Phenomenological aspects of new physics at high energy hadron colliders, Ph.D. thesis, 2011.
  8. A. Masiero, J. F. Nieves, and T. Yanagida, B−L violating proton decay and late cosmological baryon production, Phys. Lett. 116B, 11 (1982).
  9. R. N. Mohapatra and G. Senjanovic, Spontaneous breaking of global B−L symmetry and matter—antimatter oscillations in grand unified theories, Phys. Rev. D 27, 254 (1983).
  10. W. Buchmuller, C. Greub, and P. Minkowski, Neutrino masses, neutral vector bosons and the scale of B−L breaking, Phys. Lett. B 267, 395 (1991).
  11. Z. Kang, P. Ko, and J. Li, New avenues to heavy right-handed neutrinos with pair production at hadronic colliders, Phys. Rev. D 93, 075037 (2016).
  12. A. Das, S. Mandal, T. Nomura, and S. Shil, Heavy Majorana neutrino pair production from Z’ at hadron and lepton colliders, Phys. Rev. D 105, 095031 (2022).
  13. L.-G. Xia, Understanding the boosted decision tree methods with the weak-learner approximation, arXiv:1811.04822.
  14. L.-G. Xia, QBDT, a new boosting decision tree method with systematical uncertainties into training for high energy physics, Nucl. Instrum. Methods Phys. Res., Sect. A 930, 15 (2019).
  15. J. R. Quinlan, Induction of decision trees, Mach. Learn. 1, 81 (1986).
  16. J. R. Quinlan, Simplifying decision trees, Int. J. Man- Mach. Stud. 27, 221 (1987).
  17. L. Basso, S. Moretti, and G. M. Pruna, Phenomenology of the minimal B-L extension of the standard model: The Higgs sector, J. High Energy Phys. 10 (2009) 006.
  18. E. J. Chun, S. K. Kang, D. Y. Kim, and J. Park, Search for z′ in type-I Seesaw models, Quantum Sci. Technol. 3, 045003 (2018).
  19. S. Khalil, Low scale B−L extension of the standard model at the LHC, J. Phys. G 35, 055001 (2008).
  20. ATLAS Collaboration, Search for high-mass dilepton resonances using 139  fb(−1) of pp collision data at 13 TeV with the atlas detector, Phys. Rev. Lett. 123, 161801 (2019).
  21. A. Leike, The phenomenology of extra neutral gauge bosons, Phys. Rep. 317, 143 (1999).
  22. P. Langacker, The physics of heavy z′ gauge bosons, Rev. Mod. Phys. 81, 1199 (2009).
  23. H. L. Lai, J. Botts, J. Huston, J. G. Morfin, J. F. Owens, J. W. Qiu, W. K. Tung, and H. Weerts, Global QCD analysis and the cteq parton distributions, Phys. Rev. D 51, 4763 (1995).
  24. R. D. Ball, V. Bertone, F. Cerutti, L. D. Debbio, S. Forte, A. Guffanti, J. Rojo, and M. Ubiali, Parton distributions for the LHC run II, J. High Energy Phys. 04 (2015) 040.
  25. F. Staub, sarah4: A tool for (not only SUSY) model builders, Comput. Phys. Commun. 185, 1773 (2014).
  26. W. Porod, SPheno, a program for calculating supersymmetric spectra, SUSY particle decays and SUSY particle production at e+e− colliders, Comput. Phys. Commun. 153, 275 (2003).
  27. J. Alwall, R. Frederix, S. Frixione, V. Hirschi, F. Maltoni, O. Mattelaer, H. M. P. Victoria, T. Plehn, M. Schumann, S. Alioli, and J. R. Andersen, The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations, J. High Energy Phys. 07 (2014) 079.
  28. J. de Favereau, C. Delaere, P. Demin, A. Giammanco, V. Lemaître, A. Mertens, and M. Selvaggi, delphes3: A modular framework for fast simulation of a generic collider experiment, J. High Energy Phys. 02 (2014) 057.
  29. A. Höcker, P. Speckmayer, J. Stelzer, A. Voss, and H. D. Zech, TMVA—toolkit for multivariate data analysis, Phys. Chem. Comm. 168, 107 (2007).
  30. R. Brun and F. Rademakers, Root: An object oriented data analysis framework, in Proceedings of AIHENP’96 Workshop (1997), pp. 81–86.
  31. G. Cowan, K. Cranmer, E. Gross, and O. Vitells, Asymptotic formulae for likelihood-based tests of new physics, Eur. Phys. J. C 71, 1554 (2011); 73, 2501(E) (2013).
  32. Particle Data Group, Review of particle physics, Prog. Theor. Exp. Phys. 2024, 02A001 (2024).

Outline

Information

Phys. Rev. D 113, 015009– Published 9 January, 2026
  • Received 13 August 2025
  • Accepted 10 December 2025
Crossmark - Check for updates button
Creative Commons Logo

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.

Published by the American Physical Society

Sign In to Your Journals Account

Filter

Filter

Article Lookup

Enter a citation