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  • Open Access

Event shapes and inclusive hadron spectra at FCC-ee energies

Philip Mathew*

R. Aggarwal†

M. Kaur‡

  • CERN, 1211 Geneva 23, Switzerland

  • *Contact author: joemat007@gmail.com
  • †Contact author: ritu.aggarwal1@gmail.com
  • ‡Contact author: manjit@pu.ac.in
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Phys. Rev. D 113, 116017 – Published 18 June, 2026

DOI: https://doi.org/10.1103/243z-g9x8

Abstract

We analyze hadronic final states of e+e− annihilation through event shape observables, Thrust and C-parameter, and inclusive hadron spectra at the planned center-of-mass (c.m.) energies of the Future Circular Electron-Positron Collider (FCC-ee). Collision data is produced using Monte Carlo event generation in PYTHIA at 91.2, 160, 240, and 365 GeV. Distortions of event shapes due to initial-state photon radiation and background decays of Z pairs, W pairs, top-quark pairs, and Higgs bosons are investigated. An extraction of the strong coupling αs is performed by fitting event shape distributions to perturbative quantum chromodynamics (QCD) predictions at next-to-next-to-leading-order (NNLO) accuracy, and the sources of systematic uncertainties at high c.m. energies are discussed. Soft gluon dynamics is examined through charged particle multiplicities and momentum distributions, and energy evolution of mean values is compared with prior experimental results. The inferences from this phenomenological study provide a reference to QCD studies at future high-energy e+e− colliders.

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References (58)

  1. R. K. Ellis, W. J. Stirling, and B. R. Webber, QCD and Collider Physics (Cambridge University Press, Cambridge, England, 2011), Vol. 8, pp. 411–427.
  2. A. Deur, S. J. Brodsky, and G. F. de Téramond, Prog. Part. Nucl. Phys. 90, 1 (2016).
  3. D. d’Enterria, S. Kluth et al., J. Phys. G 51, 090501 (2024).
  4. C. Anastasiou, C. Duhr, F. Dulat , Elisabetta Furlan, Thomas Gehrmann, Franz Herzog, Achilleas Lazopoulos, and B. Mistlberger, J. High Energy Phys. 05 (2016) 058.
  5. F. Demartin, S. Forte, E. Mariani, J. Rojo, and A. Vicini, Phys. Rev. D 82, 014002 (2010).
  6. S. Heinemeyer, S. Jadach, and J. Reuter, Eur. Phys. J. Plus 136, 911 (2021).
  7. M. Riembau, Phys. Rev. Lett. 134, 221802 (2025).
  8. A. H. Hoang, Annu. Rev. Nucl. Part. Sci. 70, 225 (2020).
  9. S. Navas et al. (Particle Data Group), Phys. Rev. D 110, 030001 (2024).
  10. G. Arnison et al. (UA1 Collaboration), Phys. Lett. 107B, 320 (1981).
  11. R. Bala, I. Bautista, J. Bielčíková, and A. Ortiz, Int. J. Mod. Phys. E 25, 1642006 (2016).
  12. O. L. Kodolova, Phys. Part. Nucl. 56, 1117 (2025).
  13. H. Stone, Nucl. Phys. B, Proc. Suppl. 39, 184 (1995).
  14. H. Abramowicz and A. C. Caldwell, Rev. Mod. Phys. 71, 1275 (1999).
  15. V. Shiltsev and F. Zimmermann, Rev. Mod. Phys. 93, 015006 (2021).
  16. S. Kluth, Rep. Prog. Phys. 69, R04 (2006).
  17. E. Ploerer, arXiv:2208.08250.
  18. A. Abada, M. Abbrescia, S. AbdusSalam et al., Eur. Phys. J. C 79, 474 (2019).
  19. T. Sjöstrand, Phys. Scr. T 158, 014002 (2013).
  20. F. Gross, E. Klempt et al., Eur. Phys. J. C 83, 1125 (2023).
  21. M. Benedikt, F. Zimmermann, B. Auchmann, Bartmann et al., Eur. Phys. J. C 85, 1468 (2025).
  22. D. d’Enterria, P. Z. Skands et al., arXiv:1512.05194.
  23. D. d’Enterria et al., arXiv:1702.01329.
  24. V. Del Duca, C. Duhr, A. Kardos, G. Somogyi, and Z. Trócsányi, Phys. Rev. Lett. 117, 152004 (2016).
  25. R. Abbate, M. Fickinger, A. H. Hoang, V. Mateu, and I. W. Stewart, Phys. Rev. D 83, 074021 (2011).
  26. A. H. Hoang, D. W. Kolodrubetz, V. Mateu, and I. W. Stewart, Phys. Rev. D 91, 094018 (2015).
  27. B. Bambah et al., in LEP Physics Workshop (CERN, Geneva, 1989), https://inspirehep.net/literature/280404.
  28. P. Skands, in AIP Conference Proceedings (AIP, 2005), Vol. 792, p. 73–84, https://pubs.aip.org/aip/acp/article/792/1/73/653444/QCD-amp-Event-Generators.
  29. T. Sjöstrand, S. Ask, J. R. Christiansen, R. Corke, N. Desai, P. Ilten, S. Mrenna, S. Prestel, C. O. Rasmussen, and P. Z. Skands, Comput. Phys. Commun. 191, 159–177 (2015).
  30. ALEPH Collaboration, Eur. Phys. J. C 35, 457 (2004).
  31. P. Achard et al. (L3 Collaboration), Phys. Rep. 399, 71 (2004).
  32. J. Schieck, arXiv:hep-ex/0312036.
  33. M. Acciarri et al. (L3 Collaboration), Phys. Lett. B 404, 390 (1997).
  34. Physics at LEP2, CERN, Geneva, 1996, composed by 3 sessions.
  35. A. Denner, S. Dittmaier, T. Gehrmann, and C. Kurz, Proc. Sci. RADCOR2009 (2010) 056 arXiv:1001.4467.
  36. T. I. S. Group, arXiv:2502.21223.
  37. M. Dam, Nucl. Instrum. Methods Phys. Res., Sect. A 1080, 170648 (2025).
  38. R. Barate et al., Eur. Phys. J. C 18, 1 (2000).
  39. K. Chetyrkin, A. Kataev, and F. Tkachov, Phys. Lett. 85B, 277 (1979).
  40. S. Weinzierl, J. High Energy Phys. 06 (2009) 041.
  41. M. Hatlo, F. James, P. Mato, L. Moneta, M. Winkler, and A. Zsenei, IEEE Trans. Nucl. Sci. 52, 2818 (2005).
  42. G. Dissertori, A. G.-D. Ridder, T. Gehrmann, E. Glover, G. Heinrich, G. Luisoni, and H. Stenzel, J. High Energy Phys. 08 (2009) 036.
  43. R. W. L. Jones, M. Ford, G. P. Salam, H. Stenzel, and D. Wicke, J. High Energy Phys. 12 (2003) 007.
  44. O. Biebel, arXiv:hep-ex/9912051.
  45. J. de Favereau, C. Delaere, P. Demin, A. Giammanco, V. Lemaître, A. Mertens, and M. Selvaggi, J. High Energy Phys. 02 (2014) 057.
  46. Y. I. Azimov, Y. L. Dokshitzer, V. A. Khoze, and S. Trovan, Z. Phys. C Part. Fields 27, 65 (1985).
  47. Y. I. Azimov, Y. L. Dokshitzer, V. A. Khoze, and S. Troyan, Z. Phys. C Part. Fields 31, 213 (1986).
  48. S. Lupia and W. Ochs, Phys. Lett. B 418, 214 (1998).
  49. I. Dremin and J. Gary, Phys. Rep. 349, 301 (2001).
  50. A. Capella, I. M. Dremin, J. W. Gary, V. A. Nechitailo, and J. T. T. Van, Phys. Rev. D 61, 074009 (2000).
  51. W. Braunschweig et al. (TASSO Collaboration), Z. Phys. C 45, 193 (1989).
  52. H. W. Zheng et al. (The AMY Collaboration), Phys. Rev. D 42, 737 (1990).
  53. B. I. Ermolaev and V. S. Fadin, JETP Lett. 33, 269 (1981).
  54. Y. L. Dokshitzer, V. A. Khoze, S. I. Troyan, and A. H. Mueller, Rev. Mod. Phys. 60, 373 (1988).
  55. C. Fong and B. Webber, Phys. Lett. B 229, 289 (1989).
  56. V. A. Khoze and W. Ochs, Int. J. Mod. Phys. A 12, 2949 (1997).
  57. W. Braunschweig et al. (TASSO Collaboration), Z. Phys. C 47, 187 (1990).
  58. A. Kardos, G. Somogyi, and A. Verbytskyi, Eur. Phys. J. C 81, 292 (2021).

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Phys. Rev. D 113, 116017– Published 18 June, 2026
  • Received 4 March 2026
  • Accepted 19 May 2026
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