Precision natural SUSY at CEPC, FCC-ee, and ILC

  • JiJi FanEmail author
  • Matthew Reece
  • Lian-Tao Wang
Open Access
Regular Article - Theoretical Physics


Testing the idea of naturalness is and will continue to be one of the most important goals of high energy physics experiments. It will play a central role in the physics program of future colliders. In this paper, we present projections of the reach of natural SUSY at future lepton colliders: CEPC, FCC-ee and ILC. We focus on the observables which give the strongest reach, the electroweak precision observables (for left-handed stops), and Higgs to gluon and photon decay rates (for both left- and right-handed stops). There is a “blind spot” when the stop mixing parameter X t is approximately equal to the average stop mass. We argue that in natural scenarios, bounds on the heavy Higgs bosons from tree-level mixing effects that modify the \( hb\overline{b} \) coupling together with bounds from bsγ play a complementary role in probing the blind spot region. For specific natural SUSY scenarios such as folded SUSY in which the top partners do not carry Standard Model color charges, electroweak precision observables could be the most sensitive probe. In all the scenarios discussed in this paper, the combined set of precision measurements will probe down to a few percent in fine-tuning.


Supersymmetry Phenomenology 


Open Access

This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.


  1. [1]
    S. Dimopoulos and G.F. Giudice, Naturalness constraints in supersymmetric theories with nonuniversal soft terms, Phys. Lett. B 357 (1995) 573 [hep-ph/9507282] [INSPIRE].ADSCrossRefGoogle Scholar
  2. [2]
    A.G. Cohen, D.B. Kaplan and A.E. Nelson, The more minimal supersymmetric standard model, Phys. Lett. B 388 (1996) 588 [hep-ph/9607394] [INSPIRE].ADSCrossRefGoogle Scholar
  3. [3]
    R. Kitano and Y. Nomura, Supersymmetry, naturalness and signatures at the LHC, Phys. Rev. D 73 (2006) 095004 [hep-ph/0602096] [INSPIRE].
  4. [4]
    M. Perelstein and C. Spethmann, A collider signature of the supersymmetric golden region, JHEP 04 (2007) 070 [hep-ph/0702038] [INSPIRE].
  5. [5]
    R. Barbier et al., R-parity violating supersymmetry, Phys. Rept. 420 (2005) 1 [hep-ph/0406039] [INSPIRE].ADSCrossRefGoogle Scholar
  6. [6]
    C. Csáki, Y. Grossman and B. Heidenreich, MFV SUSY: A Natural Theory for R-Parity Violation, Phys. Rev. D 85 (2012) 095009 [arXiv:1111.1239] [INSPIRE].ADSGoogle Scholar
  7. [7]
    M.J. Strassler and K.M. Zurek, Echoes of a hidden valley at hadron colliders, Phys. Lett. B 651 (2007) 374 [hep-ph/0604261] [INSPIRE].ADSCrossRefGoogle Scholar
  8. [8]
    M.J. Strassler, Possible effects of a hidden valley on supersymmetric phenomenology, hep-ph/0607160 [INSPIRE].
  9. [9]
    T. Han, Z. Si, K.M. Zurek and M.J. Strassler, Phenomenology of hidden valleys at hadron colliders, JHEP 07 (2008) 008 [arXiv:0712.2041] [INSPIRE].ADSCrossRefGoogle Scholar
  10. [10]
    J. Fan, M. Reece and J.T. Ruderman, Stealth Supersymmetry, JHEP 11 (2011) 012 [arXiv:1105.5135] [INSPIRE].ADSCrossRefGoogle Scholar
  11. [11]
    J. Fan, M. Reece and J.T. Ruderman, A Stealth Supersymmetry Sampler, JHEP 07 (2012) 196 [arXiv:1201.4875] [INSPIRE].ADSCrossRefGoogle Scholar
  12. [12]
    T.J. LeCompte and S.P. Martin, Large Hadron Collider reach for supersymmetric models with compressed mass spectra, Phys. Rev. D 84 (2011) 015004 [arXiv:1105.4304] [INSPIRE].ADSGoogle Scholar
  13. [13]
    T.J. LeCompte and S.P. Martin, Compressed supersymmetry after 1/fb at the Large Hadron Collider, Phys. Rev. D 85 (2012) 035023 [arXiv:1111.6897] [INSPIRE].ADSGoogle Scholar
  14. [14]
    P.W. Graham, D.E. Kaplan, S. Rajendran and P. Saraswat, Displaced Supersymmetry, JHEP 07 (2012) 149 [arXiv:1204.6038] [INSPIRE].ADSCrossRefGoogle Scholar
  15. [15]
    P.W. Graham, S. Rajendran and P. Saraswat, Supersymmetric crevices: Missing signatures of R -parity violation at the LHC, Phys. Rev. D 90 (2014) 075005 [arXiv:1403.7197] [INSPIRE].ADSGoogle Scholar
  16. [16]
    D.S.M. Alves, J. Liu and N. Weiner, Hiding Missing Energy in Missing Energy, JHEP 04 (2015) 088 [arXiv:1312.4965] [INSPIRE].ADSCrossRefGoogle Scholar
  17. [17]
    A. Katz, M. Reece and A. Sajjad, Naturalness, bsγ and SUSY heavy Higgses, JHEP 10 (2014) 102 [arXiv:1406.1172] [INSPIRE].ADSCrossRefGoogle Scholar
  18. [18]
    U. Baur and M. Demarteau, Precision electroweak physics at future collider experiments, eConf C 960625 (1996) LTH085 [hep-ph/9611334] [INSPIRE].
  19. [19]
    J.F. Gunion, L. Poggioli, R.J. Van Kooten, C. Kao and P. Rowson, Higgs boson discovery and properties, eConf C 960625 (1996) LTH092 [hep-ph/9703330] [INSPIRE].
  20. [20]
    S. Heinemeyer, T. Mannel and G. Weiglein, Implications of results from Z threshold running and W W threshold running, hep-ph/9909538 [INSPIRE].
  21. [21]
    R. Hawkings and K. Monig, Electroweak and CP-violation physics at a linear collider Z factory, Eur. Phys. J. direct C 1 (1999) 8 [hep-ex/9910022] [INSPIRE].Google Scholar
  22. [22]
    J. Erler, S. Heinemeyer, W. Hollik, G. Weiglein and P.M. Zerwas, Physics impact of GigaZ, Phys. Lett. B 486 (2000) 125 [hep-ph/0005024] [INSPIRE].ADSCrossRefGoogle Scholar
  23. [23]
    H. Baer et al., The International Linear Collider Technical Design Report. Volume 2: Physics, arXiv:1306.6352 [INSPIRE].
  24. [24]
    TLEP Design Study Working Group collaboration, M. Bicer et al., First Look at the Physics Case of TLEP, JHEP 01 (2014) 164 [arXiv:1308.6176] [INSPIRE].
  25. [25]
    D. Asner et al., ILC Higgs White Paper, arXiv:1310.0763 [INSPIRE].
  26. [26]
    S. Dawson et al., Higgs Working Group Report of the Snowmass 2013 Community Planning Study, arXiv:1310.8361 [INSPIRE].
  27. [27]
    M. Baak et al., Study of Electroweak Interactions at the Energy Frontier, arXiv:1310.6708 [INSPIRE].
  28. [28]
    G. Burdman, Z. Chacko, H.-S. Goh and R. Harnik, Folded supersymmetry and the LEP paradox, JHEP 02 (2007) 009 [hep-ph/0609152] [INSPIRE].ADSCrossRefGoogle Scholar
  29. [29]
    J. Fan, M. Reece and L.-T. Wang, Possible Futures of Electroweak Precision: ILC, FCC-ee and CEPC, arXiv:1411.1054 [INSPIRE].
  30. [30]
    R. Barbieri and G.F. Giudice, Upper Bounds on Supersymmetric Particle Masses, Nucl. Phys. B 306 (1988) 63 [INSPIRE].ADSCrossRefGoogle Scholar
  31. [31]
    A. Pomarol and D. Tommasini, Horizontal symmetries for the supersymmetric flavor problem, Nucl. Phys. B 466 (1996) 3 [hep-ph/9507462] [INSPIRE].ADSCrossRefGoogle Scholar
  32. [32]
    J. Fan and M. Reece, A New Look at Higgs Constraints on Stops, JHEP 06 (2014) 031 [arXiv:1401.7671] [INSPIRE].ADSCrossRefGoogle Scholar
  33. [33]
    M.E. Peskin and T. Takeuchi, Estimation of oblique electroweak corrections, Phys. Rev. D 46 (1992) 381 [INSPIRE].ADSGoogle Scholar
  34. [34]
    M.E. Peskin and T. Takeuchi, A New constraint on a strongly interacting Higgs sector, Phys. Rev. Lett. 65 (1990) 964 [INSPIRE].ADSCrossRefGoogle Scholar
  35. [35]
    D.C. Kennedy and B.W. Lynn, Electroweak Radiative Corrections with an Effective Lagrangian: Four Fermion Processes, Nucl. Phys. B 322 (1989) 1 [INSPIRE].ADSCrossRefGoogle Scholar
  36. [36]
    B. Holdom and J. Terning, Large corrections to electroweak parameters in technicolor theories, Phys. Lett. B 247 (1990) 88 [INSPIRE].ADSCrossRefGoogle Scholar
  37. [37]
    M. Golden and L. Randall, Radiative Corrections to Electroweak Parameters in Technicolor Theories, Nucl. Phys. B 361 (1991) 3 [INSPIRE].ADSCrossRefGoogle Scholar
  38. [38]
    Z. Han and W. Skiba, Effective theory analysis of precision electroweak data, Phys. Rev. D 71 (2005) 075009 [hep-ph/0412166] [INSPIRE].ADSGoogle Scholar
  39. [39]
    Z. Han, Effective Theories and Electroweak Precision Constraints, Int. J. Mod. Phys. A 23 (2008) 2653 [arXiv:0807.0490] [INSPIRE].ADSCrossRefzbMATHGoogle Scholar
  40. [40]
    B. Grzadkowski, M. Iskrzynski, M. Misiak and J. Rosiek, Dimension-Six Terms in the Standard Model Lagrangian, JHEP 10 (2010) 085 [arXiv:1008.4884] [INSPIRE].ADSCrossRefzbMATHGoogle Scholar
  41. [41]
    M. Drees, K. Hagiwara and A. Yamada, Process independent radiative corrections in the minimal supersymmetric standard model, Phys. Rev. D 45 (1992) 1725 [INSPIRE].ADSGoogle Scholar
  42. [42]
    H.E. Haber and R. Hempfling, Can the mass of the lightest Higgs boson of the minimal supersymmetric model be larger than m(Z)?, Phys. Rev. Lett. 66 (1991) 1815 [INSPIRE].ADSCrossRefGoogle Scholar
  43. [43]
    R. Barbieri, M. Frigeni and F. Caravaglios, The Supersymmetric Higgs for heavy superpartners, Phys. Lett. B 258 (1991) 167 [INSPIRE].ADSCrossRefGoogle Scholar
  44. [44]
    J.A. Casas, J.R. Espinosa, M. Quirós and A. Riotto, The Lightest Higgs boson mass in the minimal supersymmetric standard model, Nucl. Phys. B 436 (1995) 3 [Erratum ibid. B 439 (1995) 466] [hep-ph/9407389] [INSPIRE].
  45. [45]
    M. Carena, J.R. Espinosa, M. Quirós and C.E.M. Wagner, Analytical expressions for radiatively corrected Higgs masses and couplings in the MSSM, Phys. Lett. B 355 (1995) 209 [hep-ph/9504316] [INSPIRE].ADSCrossRefGoogle Scholar
  46. [46]
    C. Grojean, W. Skiba and J. Terning, Disguising the oblique parameters, Phys. Rev. D 73 (2006) 075008 [hep-ph/0602154] [INSPIRE].ADSGoogle Scholar
  47. [47]
    B. Henning, X. Lu and H. Murayama, What do precision Higgs measurements buy us?, arXiv:1404.1058 [INSPIRE].
  48. [48]
    B. Henning, X. Lu and H. Murayama, How to use the Standard Model effective field theory, arXiv:1412.1837 [INSPIRE].
  49. [49]
    J.R. Espinosa, C. Grojean, V. Sanz and M. Trott, NSUSY fits, JHEP 12 (2012) 077 [arXiv:1207.7355] [INSPIRE].ADSCrossRefGoogle Scholar
  50. [50]
    W. Buchmüller and D. Wyler, Effective Lagrangian Analysis of New Interactions and Flavor Conservation, Nucl. Phys. B 268 (1986) 621 [INSPIRE].ADSCrossRefGoogle Scholar
  51. [51]
    R.J. Oakes, J.M. Yang and B.-L. Young, Implications of LEP/SLD data for new physics in \( Zb\overline{b} \) couplings, Phys. Rev. D 61 (2000) 075007 [hep-ph/9911388] [INSPIRE].ADSGoogle Scholar
  52. [52]
    M. Boulware and D. Finnell, Radiative corrections to BR \( \left(Z\to b\overline{b}\right) \) in the minimal supersymmetric standard model, Phys. Rev. D 44 (1991) 2054 [INSPIRE].ADSGoogle Scholar
  53. [53]
    J.D. Wells, C.F. Kolda and G.L. Kane, Implications of Gamma \( \left(Z\to b\overline{b}\right) \) for supersymmetry searches and model building, Phys. Lett. B 338 (1994) 219 [hep-ph/9408228] [INSPIRE].ADSCrossRefGoogle Scholar
  54. [54]
    M.S. Amjad et al., A precise determination of top quark electro-weak couplings at the ILC operating at \( \sqrt{s}=500 \) GeV, arXiv:1307.8102 [INSPIRE].
  55. [55]
    D. Asner et al., Top quark precision physics at the International Linear Collider, arXiv:1307.8265 [INSPIRE].
  56. [56]
    M. Carena, S. Gori, N.R. Shah and C.E.M. Wagner, A 125 GeV SM-like Higgs in the MSSM and the γγ rate, JHEP 03 (2012) 014 [arXiv:1112.3336] [INSPIRE].ADSCrossRefGoogle Scholar
  57. [57]
    A. Arvanitaki and G. Villadoro, A Non Standard Model Higgs at the LHC as a Sign of Naturalness, JHEP 02 (2012) 144 [arXiv:1112.4835] [INSPIRE].ADSCrossRefGoogle Scholar
  58. [58]
    K. Blum, R.T. D’Agnolo and J. Fan, Natural SUSY Predicts: Higgs Couplings, JHEP 01 (2013) 057 [arXiv:1206.5303] [INSPIRE].ADSCrossRefGoogle Scholar
  59. [59]
    G.D. Kribs, A. Martin and A. Menon, Natural Supersymmetry and Implications for Higgs physics, Phys. Rev. D 88 (2013) 035025 [arXiv:1305.1313] [INSPIRE].ADSGoogle Scholar
  60. [60]
    J.R. Ellis, M.K. Gaillard and D.V. Nanopoulos, A Phenomenological Profile of the Higgs Boson, Nucl. Phys. B 106 (1976) 292 [INSPIRE].ADSCrossRefGoogle Scholar
  61. [61]
    M.A. Shifman, A.I. Vainshtein, M.B. Voloshin and V.I. Zakharov, Low-Energy Theorems for Higgs Boson Couplings to Photons, Sov. J. Nucl. Phys. 30 (1979) 711 [INSPIRE].Google Scholar
  62. [62]
    N. Craig, C. Englert and M. McCullough, New Probe of Naturalness, Phys. Rev. Lett. 111 (2013) 121803 [arXiv:1305.5251] [INSPIRE].ADSCrossRefGoogle Scholar
  63. [63]
    C. Englert and M. McCullough, Modified Higgs Sectors and NLO Associated Production, JHEP 07 (2013) 168 [arXiv:1303.1526] [INSPIRE].ADSCrossRefGoogle Scholar
  64. [64]
    S. Gori and I. Low, Precision Higgs Measurements: Constraints from New Oblique Corrections, JHEP 09 (2013) 151 [arXiv:1307.0496] [INSPIRE].ADSCrossRefGoogle Scholar
  65. [65]
    N. Craig, M. Farina, M. McCullough and M. Perelstein, Precision Higgsstrahlung as a Probe of New Physics, JHEP 03 (2015) 146 [arXiv:1411.0676] [INSPIRE].CrossRefGoogle Scholar
  66. [66]
    R. Barbieri and G.F. Giudice, bsγ decay and supersymmetry, Phys. Lett. B 309 (1993) 86 [hep-ph/9303270] [INSPIRE].ADSCrossRefGoogle Scholar
  67. [67]
    Y. Okada, Light stop and the bsγ process, Phys. Lett. B 315 (1993) 119 [hep-ph/9307249] [INSPIRE].ADSCrossRefGoogle Scholar
  68. [68]
    K. Ishiwata, N. Nagata and N. Yokozaki, Natural Supersymmetry and bsγ constraints, Phys. Lett. B 710 (2012) 145 [arXiv:1112.1944] [INSPIRE].ADSCrossRefGoogle Scholar
  69. [69]
    W. Altmannshofer, M. Carena, N.R. Shah and F. Yu, Indirect Probes of the MSSM after the Higgs Discovery, JHEP 01 (2013) 160 [arXiv:1211.1976] [INSPIRE].ADSCrossRefGoogle Scholar
  70. [70]
    T. Gherghetta, B. von Harling, A.D. Medina and M.A. Schmidt, The price of being SM-like in SUSY, JHEP 04 (2014) 180 [arXiv:1401.8291] [INSPIRE].ADSCrossRefGoogle Scholar
  71. [71]
    R.S. Gupta, M. Montull and F. Riva, SUSY Faces its Higgs Couplings, JHEP 04 (2013) 132 [arXiv:1212.5240] [INSPIRE].ADSMathSciNetCrossRefzbMATHGoogle Scholar
  72. [72]
    P.L. Cho and E.H. Simmons, Searching for G3 in \( t\overline{t} \) production, Phys. Rev. D 51 (1995) 2360 [hep-ph/9408206] [INSPIRE].ADSGoogle Scholar
  73. [73]
    M.T. Grisaru and H.N. Pendleton, Some Properties of Scattering Amplitudes in Supersymmetric Theories, Nucl. Phys. B 124 (1977) 81 [INSPIRE].ADSMathSciNetCrossRefGoogle Scholar
  74. [74]
    ECFA/DESY LC Physics Working Group collaboration, J.A. Aguilar-Saavedra et al., TESLA: The Superconducting electron positron linear collider with an integrated x-ray laser laboratory. Technical design report. Part 3. Physics at an e + e linear collider, hep-ph/0106315 [INSPIRE].
  75. [75]
    D.S.M. Alves, J. Galloway, J.T. Ruderman and J.R. Walsh, Running Electroweak Couplings as a Probe of New Physics, JHEP 02 (2015) 007 [arXiv:1410.6810] [INSPIRE].ADSCrossRefGoogle Scholar
  76. [76]
    N. Blinov and D.E. Morrissey, Vacuum Stability and the MSSM Higgs Mass, JHEP 03 (2014) 106 [arXiv:1310.4174] [INSPIRE].ADSCrossRefGoogle Scholar
  77. [77]
    A. Kusenko, P. Langacker and G. Segre, Phase transitions and vacuum tunneling into charge and color breaking minima in the MSSM, Phys. Rev. D 54 (1996) 5824 [hep-ph/9602414] [INSPIRE].ADSGoogle Scholar
  78. [78]
    SLD Electroweak Group, DELPHI, ALEPH, SLD, SLD Heavy Flavour Group, OPAL, LEP Electroweak Working Group and L3 collaborations, S. Schael et al., Precision electroweak measurements on the Z resonance, Phys. Rept. 427 (2006) 257 [hep-ex/0509008] [INSPIRE].
  79. [79]
    G. Alexander et al., TESLA: The superconducting electron positron linear collider with an integrated X-ray laser laboratory. Technical design report. Part 4: A detector for TESLA (2001).Google Scholar
  80. [80]
  81. [81]
    A. Freitas, Higher-order electroweak corrections to the partial widths and branching ratios of the Z boson, JHEP 04 (2014) 070 [arXiv:1401.2447] [INSPIRE].ADSCrossRefGoogle Scholar
  82. [82]
    C. Cheung, L.J. Hall, D. Pinner and J.T. Ruderman, Prospects and Blind Spots for Neutralino Dark Matter, JHEP 05 (2013) 100 [arXiv:1211.4873] [INSPIRE].ADSCrossRefGoogle Scholar
  83. [83]
    J. Guo, Z. Kang, J. Li and T. Li, Implications of Higgs Sterility for the Higgs and Stop Sectors, arXiv:1308.3075 [INSPIRE].
  84. [84]
    R.T. D’Agnolo, E. Kuflik and M. Zanetti, Fitting the Higgs to Natural SUSY, JHEP 03 (2013) 043 [arXiv:1212.1165] [INSPIRE].ADSCrossRefGoogle Scholar
  85. [85]
    G. Burdman, Z. Chacko, H.-S. Goh, R. Harnik and C.A. Krenke, The Quirky Collider Signals of Folded Supersymmetry, Phys. Rev. D 78 (2008) 075028 [arXiv:0805.4667] [INSPIRE].ADSGoogle Scholar
  86. [86]
    G. Burdman, Z. Chacko, R. Harnik, L. de Lima and C.B. Verhaaren, Colorless Top Partners, a 125 GeV Higgs and the Limits on Naturalness, Phys. Rev. D 91 (2015) 055007 [arXiv:1411.3310] [INSPIRE].ADSGoogle Scholar
  87. [87]
    T. Han, Z. Liu and J. Sayre, Potential Precision on Higgs Couplings and Total Width at the ILC, Phys. Rev. D 89 (2014) 113006 [arXiv:1311.7155] [INSPIRE].ADSGoogle Scholar
  88. [88]
    M.E. Peskin, Estimation of LHC and ILC Capabilities for Precision Higgs Boson Coupling Measurements, [arXiv:1312.4974] [INSPIRE].

Copyright information

© The Author(s) 2015

Authors and Affiliations

  1. 1.Department of PhysicsSyracuse UniversitySyracuseUnited States
  2. 2.Department of PhysicsHarvard UniversityCambridgeUnited States
  3. 3.Enrico Fermi Institute and Kavli Institute for Cosmological PhysicsUniversity of ChicagoChicagoUnited States

Personalised recommendations