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Leptoquark Searches at TeV Scale Using Neural Networks at Hadron Collider

Published 13 May 2024 in hep-ph and hep-ex | (2405.08090v2)

Abstract: Several discrepancies in the decay of B-meson decay have drawn a lot of interest in the leptoquarks (LQ), making them an exciting discovery. The current research aims to discover the pair-production of leptoquarks that links strongly to the third generation of quarks and leptons at the center of mass energy $\sqrt{s}$=14 TeV, via proton-proton collisions at the Large Hadron Collider (LHC). Based on the lepton-quark coupling parameters and branching fractions, we separated our search into various benchmark points. The leading order (LO) signals and background processes are generated, while parton showering and hadronization is also performed to simulate the detector effects. The Boosted Decision Trees (BDTs), Multilayer Perceptron (MLP), and Likelihood (LH) methods are effective in improving signal-background discrimination compared to traditional cut-based analysis. The results indicate that these machine learning methods can significantly enhance the sensitivity in probing for new physics signals, such as LQs, at two different integrated luminosities. Specifically, the use of BDTs, MLP, and LH has led to higher signal significances and improved signal efficiency in both hadronic and semi-leptonic decay modes. The results suggest that the LQ masses of 500 GeV and 2.0 TeV in fully hadronic decay modes can be accurately probed with signal significance 176.70 (17.6) and 184.27 (0.01) for MVA (cut-based) at 1000 $fb{-1}$, respectively. Similarly, in semi-leptonic decay mode the signal significance values are 168.56 and 181.89 at lowest and highest selected LQ masses respectively for MVA method only. The enhanced numbers by a factor of 2 are also reported at 3000 $fb{-1}$.

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References (27)
  1. J. Lees, V. Poireau, V. Tisserand, J. G. Tico, E. Grauges, A. Palano, G. Eigen, B. Stugu, D. N. Brown, L. Kerth, et al., “Evidence for an excess of B¯→d(∗)⁢τ(−)⁢ν¯⁢τ→¯𝐵superscript𝑑superscript𝜏¯𝜈𝜏\bar{B}\to d^{(*)}\tau^{(-)}\bar{\nu}{\tau}over¯ start_ARG italic_B end_ARG → italic_d start_POSTSUPERSCRIPT ( ∗ ) end_POSTSUPERSCRIPT italic_τ start_POSTSUPERSCRIPT ( - ) end_POSTSUPERSCRIPT over¯ start_ARG italic_ν end_ARG italic_τ decays,” Physical review letters, vol. 109, no. 10, p. 101802, 2012.
  2. B. Bhattacharya, A. Datta, D. London, and S. Shivashankara, “Simultaneous explanation of the rk and r (d (*)) puzzles,” Physics Letters B, vol. 742, pp. 370–374, 2015.
  3. J. C. Pati and A. Salam, “Lepton number as the fourth” color”,” Physical Review D, vol. 10, no. 1, p. 275, 1974.
  4. H. Georgi and S. L. Glashow, “Unity of all elementary-particle forces,” Physical Review Letters, vol. 32, no. 8, p. 438, 1974.
  5. S. Dimopoulos and L. Susskind, “Mass without scalars,” Nuclear Physics B, vol. 155, no. 1, pp. 237–252, 1979.
  6. S. Dimopoulos, “Technicoloured signatures,” Nuclear Physics B, vol. 168, no. 1, pp. 69–92, 1980.
  7. E. Eichten and K. Lane, “Dynamical breaking of weak interaction symmetries,” Physics Letters B, vol. 90, no. 1-2, pp. 125–130, 1980.
  8. V. Angelopoulos, J. Ellis, H. Kowalski, D. V. Nanopoulos, N. Tracas, and F. Zwirner, “Search for new quarks suggested by the superstring,” Nuclear Physics B, vol. 292, pp. 59–92, 1987.
  9. W. Buchmüller and D. Wyler, “Constraints on su (5)-type leptoquarks,” Physics Letters B, vol. 177, no. 3-4, pp. 377–382, 1986.
  10. R. Iuppa, A. Di Luca, C. Atlas, et al., “Searches for third-generation scalar leptoquarks in s=13𝑠13\sqrt{s}=13square-root start_ARG italic_s end_ARG = 13  tev pp collisions with the atlas detector,” INTERNATIONAL JOURNAL OF HIGH ENERGY PHYSICS, vol. 2019, no. 6, 2019.
  11. C. Lo, C. PENG, K. TAM, L. Pizzimento, A. collaboration, et al., “Search for pair production of third-generation scalar leptoquarks decaying into a top quark and a τ𝜏\tauitalic_τ leptonin pp collisions at s=13𝑠13\sqrt{s}=13square-root start_ARG italic_s end_ARG = 13  tev with the atlas detector,” Journal of High Energy Physics, 2021.
  12. A. M. Sirunyan, A. Tumasyan, W. Adam, F. Ambrogi, E. Asilar, T. Bergauer, J. Brandstetter, M. Dragicevic, J. Erö, A. E. Del Valle, et al., “Search for pair production of first-generation scalar leptoquarks at s𝑠\sqrt{s}square-root start_ARG italic_s end_ARG= 13 tev,” Physical Review D, vol. 99, no. 5, p. 052002, 2019.
  13. G. Aad, B. Abbott, D. C. Abbott, A. A. Abud, K. Abeling, D. K. Abhayasinghe, S. H. Abidi, O. AbouZeid, N. L. Abraham, H. Abramowicz, et al., “Search for a scalar partner of the top quark in the all-hadronic tt¯ plus missing transverse momentum final state at s=13𝑠13\sqrt{s}=13square-root start_ARG italic_s end_ARG = 13 tev with the atlas detector,” The European Physical Journal C, vol. 80, no. 8, p. 737, 2020.
  14. G. Aad, B. Abbott, D. C. Abbott, A. A. Abud, K. Abeling, D. K. Abhayasinghe, S. H. Abidi, O. AbouZeid, H. Abramowicz, H. Abreu, et al., “Search for new phenomena in p p collisions in final states with tau leptons, b-jets, and missing transverse momentum with the atlas detector,” Physical Review D, vol. 104, no. 11, p. 112005, 2021.
  15. P. Bandyopadhyay and R. Mandal, “Vacuum stability in an extended standard model with a leptoquark,” Physical Review D, vol. 95, no. 3, p. 035007, 2017.
  16. C. collaboration et al., “Search for pair production of second-generation leptoquarks at s𝑠\sqrt{s}square-root start_ARG italic_s end_ARG= 13 tev,” arXiv preprint arXiv:1808.05082, 2018.
  17. A. Collaboration et al., “Search for pair production of scalar leptoquarks decaying into first-or second-generation leptons and top quarks in proton-proton collisions at s=13𝑠13\sqrt{s}=13square-root start_ARG italic_s end_ARG = 13 tev with the atlas detector,” arXiv preprint arXiv:2010.02098, 2020.
  18. C. collaboration et al., “Search for singly and pair-produced leptoquarks coupling to third-generation fermions in proton-proton collisions at s𝑠\sqrt{s}square-root start_ARG italic_s end_ARG= 13 tev,” arXiv preprint arXiv:2012.04178, 2020.
  19. G. Aad, B. Abbott, K. Abeling, S. Abidi, A. Aboulhorma, H. Abramowicz, H. Abreu, Y. Abulaiti, A. A. Hoffman, B. Acharya, et al., “Search for pair production of third-generation leptoquarks decaying into a bottom quark and a τ𝜏\tauitalic_τ-lepton with the atlas detector,” The European Physical Journal C, vol. 83, no. 11, p. 1075, 2023.
  20. M. Hirsch, H. Klapdor-Kleingrothaus, and S. Kovalenko, “New leptoquark mechanism of neutrinoless double β𝛽\betaitalic_β decay,” Physical Review D, vol. 54, no. 7, p. R4207, 1996.
  21. A. Davies and X.-G. He, “Tree-level scalar-fermion interactions consistent with the symmetries of the standard model,” Physical Review D, vol. 43, no. 1, p. 225, 1991.
  22. S. Maes, “A bold prediction on the muon anomalous magnetic moment, and expected resulted to be published on april 7, 2021 by the fermilab muon g-2, and its explanation,” 2022.
  23. A. Belyaev, C. Leroy, R. Mehdiyev, and A. Pukhov, “Leptoquark single and pair production at lhc with calchep/comphep in the complete model,” Journal of High Energy Physics, vol. 2005, no. 09, p. 005, 2005.
  24. J. Hewett and S. Pakvasa, “Scalar-leptoquark production at hadron colliders,” Physical Review D, vol. 37, no. 11, p. 3165, 1988.
  25. R. Brun and F. Rademakers, “Root—an object oriented data analysis framework,” Nuclear instruments and methods in physics research section A: accelerators, spectrometers, detectors and associated equipment, vol. 389, no. 1-2, pp. 81–86, 1997.
  26. A. Hoecker, P. Speckmayer, J. Stelzer, J. Therhaag, E. von Toerne, H. Voss, M. Backes, T. Carli, O. Cohen, A. Christov, et al., “Tmva-toolkit for multivariate data analysis,” arXiv preprint physics/0703039, 2007.
  27. R. Y. Choi, A. S. Coyner, J. Kalpathy-Cramer, M. F. Chiang, and J. P. Campbell, “Introduction to machine learning, neural networks, and deep learning,” Translational vision science & technology, vol. 9, no. 2, pp. 14–14, 2020.

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