Abstract
FCC-ee, a future electron–positron collider, is the first step in a future collider program aiming to improve our understanding of high-energy physics and ultimately go beyond the Standard Model. The Standard Model provides a remarkably accurate description of the laws of physics over an enormous range of distance and energy scales. However, there are aspects of the world around us that it does not explain, including the nature of dark matter and the absence of antimatter in the observed universe. The Standard Model presents theoretical puzzles, such as unexplained hierarchies and patterns of masses and mixings, as well as theoretical opportunities, in the form of portals that may access as-yet-undiscovered dark or hidden sectors. This essay explains how these physics considerations motivate FCC-ee, which will provide a flexible, powerful probe of physics at the electroweak scale and offer the potential to discover rare processes related to dark matter or otherwise hidden physics. It also situates FCC-ee in the context of other planned experiments, including its successor FCC-hh. The FCC physics program as a whole provides a roadmap for the future of particle physics extending well into the twenty-first century.
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08 July 2022
A Correction to this paper has been published: https://doi.org/10.1140/epjp/s13360-022-02959-2
Notes
Some physicists characterize neutrino masses as empirical evidence for BSM physics. I prefer to say that we have two distinct Standard Models that fit the data equally well. One has new fermionic fields that pair up with neutrinos to make lepton-number-conserving Dirac fermions. Another has nonrenormalizable operators giving neutrinos lepton-number-violating Majorana masses. (These can also coexist; theories with new fermionic fields in general allow both Dirac and Majorana mass terms.) Only data (e.g., observation of neutrinoless double beta decay) can tell us whether lepton number is conserved or not, and only the case with nonrenormalizable mass terms is incomplete as a low-energy effective field theory. I will comment more on neutrino physics at FCC below.
References
ATLAS Collaboration, G. Aad et al., Observation of a new particle in the search for the standard model higgs boson with the ATLAS detector at the LHC. Phys. Lett. B 716, 1–29 (2012)
CMS Collaboration, S. Chatrchyan et al., Observation of a new boson at a mass of 125 GeV with the CMS experiment at the LHC. Phys. Lett. B 716, 30–61 (2012)
FCC Collaboration, A. Abada et al., FCC physics opportunities: future circular collider conceptual design report volume 1. Eur. Phys. J. C 79(6), 474 (2019)
FCC Collaboration, A. Abada et al., FCC-ee: the lepton collider: future circular collider conceptual design report volume 2. Eur. Phys. J. ST 228(2), 261–623 (2019)
R. K. Ellis et al., Physics Briefing Book: Input for the European Strategy for Particle Physics Update 2020. arXiv:1910.11775 [hep-ex]
R.D. Peccei, H.R. Quinn, CP conservation in the presence of instantons. Phys. Rev. Lett. 38, 1440–1443 (1977)
L.E. Ibanez, G.G. Ross, SU(2)\(_L~\times \) U(1) symmetry breaking as a radiative effect of supersymmetry breaking in guts. Phys. Lett. B 110, 215–220 (1982)
H. Georgi, D.B. Kaplan, Composite higgs and custodial SU(2). Phys. Lett. B 145, 216–220 (1984)
V.F. Weisskopf, Of atoms, mountains, and stars—a study in qualitative physics. Science 187, 605–612 (1975)
A. Burrows, J.P. Ostriker, The astronomical reach of fundamental physics. Proc. Nat. Acad. Sci. 111, 2409 (2014)
P. Draper, H. Rzehak, A review of higgs mass calculations in supersymmetric models. Phys. Rep. 619, 1–24 (2016)
L.E.P. Polarization Collaboration, L. Arnaudon, L. Knudsen, J.P. Koutchouk, R. Olsen, M. Placidi, R. Schmidt, M. Crozon, A. Blondel, R. Assmann, B. Dehning, Measurement of LEP beam energy by resonant spin depolarization. Phys. Lett. B 284, 431–439 (1992)
M.E. Peskin, T. Takeuchi, Estimation of oblique electroweak corrections. Phys. Rev. D 46, 381–409 (1992)
P. Janot, Direct measurement of \(\alpha _{QED}(m_{Z}^{2})\) at the FCC-ee. JHEP 02, 053 (2016). arXiv:1512.05544 [hep-ph]. [Erratum: JHEP 11, 164 (2017)]
M. McCullough, An indirect model-dependent probe of the Higgs self-coupling. Phys. Rev. D 90(1), 015001 (2014)
S. Di Vita, G. Durieux, C. Grojean, J. Gu, Z. Liu, G. Panico, M. Riembau, T. Vantalon, A global view on the Higgs self-coupling at lepton colliders. JHEP 02, 178 (2018)
J. de Blas, M. Ciuchini, E. Franco, S. Mishima, M. Pierini, L. Reina, and L. Silvestrini, “Electroweak precision constraints at present and future colliders,” PoS ICHEP2016 (2017) 690, arXiv:1611.05354 [hep-ph]
M.J. Strassler, K.M. Zurek, Echoes of a hidden valley at hadron colliders. Phys. Lett. B 651, 374–379 (2007)
Z. Chacko, H.-S. Goh, R. Harnik, The Twin Higgs: Natural electroweak breaking from mirror symmetry. Phys. Rev. Lett. 96, 231802 (2006)
Z. Liu, L.-T. Wang, H. Zhang, Exotic decays of the 125 GeV Higgs boson at future \(e^+e^-\) lepton colliders. Chin. Phys. C 41(6), 063102 (2017)
J. Liu, L.-T. Wang, X.-P. Wang, W. Xue, Exposing the dark sector with future Z factories. Phys. Rev. D 97(9), 095044 (2018)
S. Antusch, E. Cazzato, O. Fischer, Sterile neutrino searches at future \(e^-e^+\), \(pp\), and \(e^-p\) colliders. Int. J. Mod. Phys. A 32(14), 1750078 (2017)
R.N. Mohapatra, J.W.F. Valle, Neutrino mass and baryon number nonconservation in superstring models. Phys. Rev. D 34, 1642 (1986)
A. Blondel, A. Freitas, J. Gluza, T. Riemann, S. Heinemeyer, S. Jadach, and P. Janot, “Theory Requirements and Possibilities for the FCC-ee and other Future High Energy and Precision Frontier Lepton Colliders,” arXiv:1901.02648 [hep-ph]
P.W. Graham, D.E. Kaplan, S. Rajendran, Cosmological relaxation of the electroweak scale. Phys. Rev. Lett. 115(22), 221801 (2015)
N. Craig, I. Garcia Garcia, and S. Koren, “The Weak Scale from Weak Gravity,” JHEP 09 (2019) 081, arXiv:1904.08426 [hep-ph]
C. Csáki, R.T. D’Agnolo, M. Geller, A. Ismail, Crunching Dilaton, Hidden naturalness. Phys. Rev. Lett. 126, 091801 (2021)
F.C.C. Collaboration, A. Abada et al., FCC-hh: The Hadron Collider: future circular collider conceptual design report volume 3. Eur. Phys. J. ST 228(4), 755–1107 (2019)
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This project is co-funded from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 951754.
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Reece, M. FCC-ee and the high-energy physics landscape. Eur. Phys. J. Plus 136, 1102 (2021). https://doi.org/10.1140/epjp/s13360-021-02104-5
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DOI: https://doi.org/10.1140/epjp/s13360-021-02104-5