Naturalness in D-brane inspired models

  • Ron De Benedetti
  • Tianjun Li
  • James A. MaxinEmail author
  • Dimitri V. Nanopoulos
Open Access
Regular Article - Theoretical Physics


We examine the naturalness of the D-brane inspired model constructed in flipped SU(5) supplemented with vector-like particles at the TeV scale, dubbed flippons. We find the model can produce a mainly Higgsino-like lightest supersymmetric particle (LSP) and small light stops, as favored by naturalness. In fact, a large trilinear scalar At term at the electroweak (EW) scale creates a large mass splitting between the top squarks, driving the light stop to near degeneracy with an LSP that is almost all Higgsino, with \( \Delta M\left({\tilde{t}}_1,{\tilde{\chi}}_1^0\right) \)< 5GeV, evading the LHC constraint on \( {\tilde{t}}_1\to c{\tilde{\chi}}_1^0 \) thus far. Given the smallness of the light stop, generating a 125 GeV light Higgs boson mass is aided by one-loop contributions from the Yukawa couplings between the flippons and Higgs fields. The resulting parameter space satisfying naturalness is rather constrained, thus we assess its viability by means of comparison to the LHC constraint on soft charm jets and direction detection limits on spin-independent cross-sections. Finally, we compute the level of electroweak fine-tuning and uncover a region with ΔEW< 30, i.e., fine-tuning better than 3%, regarded as low electroweak fine-tuning. Given the small light stop, the electroweak fine-tuning from only the top squarks is of \( \mathcal{O} \)(1), indicating no fine-tuning from neither the light stop \( {\tilde{t}}_1 \) nor the heavy stop \( {\tilde{t}}_2 \).


Supersymmetry Phenomenology Strings and branes 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]
    ATLAS and CMS collaborations, Strong SUSY results in ATLAS and CMS @ LHC run II, presented at conference Moriond EW 2019, La Thuile, Italy 16–23 March 2019.Google Scholar
  2. [2]
    ATLAS collaboration, 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 (2012) 1 [arXiv:1207.7214] [INSPIRE].
  3. [3]
    CMS collaboration, Observation of a new boson at a mass of 125 GeV with the CMS experiment at the LHC, Phys. Lett. B 716 (2012) 30 [arXiv:1207.7235] [INSPIRE].
  4. [4]
    S.M. Barr, A new symmetry breaking pattern for SO(10) and proton decay, Phys. Lett. B 112 (1982) 219 [INSPIRE].ADSMathSciNetCrossRefGoogle Scholar
  5. [5]
    J.P. Derendinger, J.E. Kim and D.V. Nanopoulos, Anti-SU(5), Phys. Lett. B 139 (1984) 170 [INSPIRE].ADSCrossRefGoogle Scholar
  6. [6]
    I. Antoniadis, J.R. Ellis, J.S. Hagelin and D.V. Nanopoulos, Supersymmetric flipped SU(5) revitalized, Phys. Lett. B 194 (1987) 231 [INSPIRE].ADSCrossRefGoogle Scholar
  7. [7]
    I. Antoniadis, J.R. Ellis, J.S. Hagelin and D.V. Nanopoulos, An improved SU(5) × U(1) model from four-dimensional string, Phys. Lett. B 208 (1988) 209 [Addendum ibid. B 213 (1988) 562] [INSPIRE].
  8. [8]
    I. Antoniadis, J.R. Ellis, J.S. Hagelin and D.V. Nanopoulos, The flipped SU(5) × U(1) string model revamped, Phys. Lett. B 231 (1989) 65 [INSPIRE].ADSMathSciNetCrossRefGoogle Scholar
  9. [9]
    J.L. Lopez, D.V. Nanopoulos and K.-J. Yuan, The search for a realistic flipped SU(5) string model, Nucl. Phys. B 399 (1993) 654 [hep-th/9203025] [INSPIRE].ADSCrossRefGoogle Scholar
  10. [10]
    J.E. Kim and B. Kyae, Flipped SU(5) from Z 12 − I orbifold with Wilson line, Nucl. Phys. B 770 (2007) 47 [hep-th/0608086] [INSPIRE].ADSCrossRefzbMATHGoogle Scholar
  11. [11]
    J.-H. Huh, J.E. Kim and B. Kyae, SU(5)flip × SU(5)′ from Z 12 − I, Phys. Rev. D 80 (2009) 115012 [arXiv:0904.1108] [INSPIRE].ADSGoogle Scholar
  12. [12]
    R. Blumenhagen, S. Moster and T. Weigand, Heterotic GUT and Standard Model vacua from simply connected Calabi-Yau manifolds, Nucl. Phys. B 751 (2006) 186 [hep-th/0603015] [INSPIRE].ADSMathSciNetCrossRefzbMATHGoogle Scholar
  13. [13]
    C.M. Chen, G.V. Kraniotis, V.E. Mayes, D.V. Nanopoulos and J.W. Walker, A supersymmetric flipped SU(5) intersecting brane world, Phys. Lett. B 611 (2005) 156 [hep-th/0501182] [INSPIRE].ADSMathSciNetCrossRefzbMATHGoogle Scholar
  14. [14]
    C.-M. Chen, V.E. Mayes and D.V. Nanopoulos, Flipped SU(5) from D-branes with type IIB fluxes, Phys. Lett. B 633 (2006) 618 [hep-th/0511135] [INSPIRE].ADSMathSciNetCrossRefzbMATHGoogle Scholar
  15. [15]
    C.-M. Chen, T. Li and D.V. Nanopoulos, Flipped and unflipped SU(5) as type IIA flux vacua, Nucl. Phys. B 751 (2006) 260 [hep-th/0604107] [INSPIRE].ADSMathSciNetCrossRefzbMATHGoogle Scholar
  16. [16]
    J. Jiang, T. Li, D.V. Nanopoulos and D. Xie, F-SU(5), Phys. Lett. B 677 (2009) 322 [arXiv:0811.2807] [INSPIRE].ADSCrossRefGoogle Scholar
  17. [17]
    J. Jiang, T. Li, D.V. Nanopoulos and D. Xie, Flipped SU(5) × U(1)X models from F-theory, Nucl. Phys. B 830 (2010) 195 [arXiv:0905.3394] [INSPIRE].ADSMathSciNetCrossRefGoogle Scholar
  18. [18]
    J. Jiang, T. Li and D.V. Nanopoulos, Testable flipped SU(5) × U(1)X models, Nucl. Phys. B 772 (2007) 49 [hep-ph/0610054] [INSPIRE].
  19. [19]
    T. Li, J.A. Maxin, D.V. Nanopoulos and J.W. Walker, The golden point of no-scale and no-parameter F-SU(5), Phys. Rev. D 83 (2011) 056015 [arXiv:1007.5100] [INSPIRE].ADSGoogle Scholar
  20. [20]
    T. Li, J.A. Maxin, D.V. Nanopoulos and J.W. Walker, The ultra-high jet multiplicity signal of stringy no-scale F-SU(5) at the \( \sqrt{s} \) = 7 TeV LHC, Phys. Rev. D 84 (2011) 076003 [arXiv:1103.4160] [INSPIRE].ADSGoogle Scholar
  21. [21]
    T. Li, J.A. Maxin, D.V. Nanopoulos and J.W. Walker, A Higgs mass shift to 125 GeV and a multi-jet supersymmetry signal: miracle of the flippons at the \( \sqrt{s} \) = 7 TeV LHC, Phys. Lett. B 710 (2012) 207 [arXiv:1112.3024] [INSPIRE].ADSCrossRefGoogle Scholar
  22. [22]
    T. Li, J.A. Maxin and D.V. Nanopoulos, The return of the king: no-scale F-SU(5), Phys. Lett. B 764 (2017) 167 [arXiv:1609.06294] [INSPIRE].ADSCrossRefGoogle Scholar
  23. [23]
    R. De Benedetti, C. Li, T. Li, A. Lux, J.A. Maxin and D.V. Nanopoulos, Inspiration from intersecting D-branes: general supersymmetry breaking soft terms in no-scale F-SU(5), Eur. Phys. J. C 78 (2018) 958 [arXiv:1809.09695] [INSPIRE].ADSCrossRefGoogle Scholar
  24. [24]
    W. Ahmed, L. Calibbi, T. Li, S. Raza, J.-S. Niu and X.-C. Wang, Naturalness and dark matter in a realistic intersecting D6-brane model, JHEP 06 (2018) 126 [arXiv:1711.10225] [INSPIRE].ADSCrossRefGoogle Scholar
  25. [25]
    T. Leggett, T. Li, J.A. Maxin, D.V. Nanopoulos and J.W. Walker, Confronting electroweak fine-tuning with no-scale supergravity, Phys. Lett. B 740 (2015) 66 [arXiv:1408.4459] [INSPIRE].ADSMathSciNetCrossRefGoogle Scholar
  26. [26]
    J.R. Ellis, K. Enqvist, D.V. Nanopoulos and F. Zwirner, Observables in low-energy superstring models, Mod. Phys. Lett. A 1 (1986) 57 [INSPIRE].ADSCrossRefGoogle Scholar
  27. [27]
    R. Barbieri and G.F. Giudice, Upper bounds on supersymmetric particle masses, Nucl. Phys. B 306 (1988) 63 [INSPIRE].ADSCrossRefGoogle Scholar
  28. [28]
    T. Li, J.A. Maxin and D.V. Nanopoulos, Probing the no-scale F-SU(5) one-parameter model via gluino searches at the LHC2, Phys. Lett. B 773 (2017) 54 [arXiv:1705.07973] [INSPIRE].ADSCrossRefGoogle Scholar
  29. [29]
    T. Li, J.A. Maxin, D.V. Nanopoulos and J.W. Walker, No-scale F-SU(5) in the light of LHC, Planck and XENON, J. Phys. G 40 (2013) 115002 [arXiv:1305.1846] [INSPIRE].ADSCrossRefGoogle Scholar
  30. [30]
    ATLAS collaboration, Exotics combined summary plots webpage,, (2016).
  31. [31]
    R. Harnik, D.T. Larson, H. Murayama and M. Thormeier, Probing the Planck scale with proton decay, Nucl. Phys. B 706 (2005) 372 [hep-ph/0404260] [INSPIRE].
  32. [32]
    J.R. Ellis, D.V. Nanopoulos and K.A. Olive, Flipped heavy neutrinos: from the solar neutrino problem to baryogenesis, Phys. Lett. B 300 (1993) 121 [hep-ph/9211325] [INSPIRE].
  33. [33]
    J.R. Ellis, J.L. Lopez, D.V. Nanopoulos and K.A. Olive, Flipped angles and phases: a systematic study, Phys. Lett. B 308 (1993) 70 [hep-ph/9303307] [INSPIRE].
  34. [34]
    T. Li, J.A. Maxin, D.V. Nanopoulos and J.W. Walker, Dark matter, proton decay and other phenomenological constraints in F-SU(5), Nucl. Phys. B 848 (2011) 314 [arXiv:1003.4186] [INSPIRE].ADSCrossRefzbMATHGoogle Scholar
  35. [35]
    Tevatron Electroweak Working Group, CDF and D0 collaborations, Combination of CDF and DO results on the mass of the top quark using up to 8.7 fb −1 at the Tevatron, arXiv:1305.3929 [INSPIRE].
  36. [36]
    WMAP collaboration, Nine-year Wilkinson Microwave Anisotropy Probe (WMAP) observations: cosmological parameter results, Astrophys. J. Suppl. 208 (2013) 19 [arXiv:1212.5226] [INSPIRE].
  37. [37]
    Planck collaboration, Planck 2018 results. VI. Cosmological parameters, arXiv:1807.06209 [INSPIRE].
  38. [38]
    Y. Huo, T. Li, D.V. Nanopoulos and C. Tong, The lightest CP-even Higgs boson mass in the testable flipped SU(5) × U(1)X models from F-theory, Phys. Rev. D 85 (2012) 116002 [arXiv:1109.2329] [INSPIRE].ADSGoogle Scholar
  39. [39]
    ATLAS collaboration, Search for dark matter and other new phenomena in events with an energetic jet and large missing transverse momentum using the ATLAS detector, JHEP 01 (2018) 126 [arXiv:1711.03301] [INSPIRE].
  40. [40]
    ATLAS collaboration, Search for supersymmetry in final states with charm jets and missing transverse momentum in 13 TeV pp collisions with the ATLAS detector, JHEP 09 (2018) 050 [arXiv:1805.01649] [INSPIRE].
  41. [41]
    Heavy Flavor Averaging Group collaboration, Compilation of B + semi-leptonic and radiative branching fractions,, (2013).
  42. [42]
    CMS and LHCb collaborations, Observation of the rare B s0μ + μ decay from the combined analysis of CMS and LHCb data, Nature 522 (2015) 68 [arXiv:1411.4413] [INSPIRE].
  43. [43]
    T. Aoyama, M. Hayakawa, T. Kinoshita and M. Nio, Complete tenth-order QED contribution to the muon g − 2, Phys. Rev. Lett. 109 (2012) 111808 [arXiv:1205.5370] [INSPIRE].ADSCrossRefGoogle Scholar
  44. [44]
    LUX collaboration, Results from a search for dark matter in the complete LUX exposure, Phys. Rev. Lett. 118 (2017) 021303 [arXiv:1608.07648] [INSPIRE].
  45. [45]
    PandaX-II collaboration, Dark matter results from first 98.7 days of data from the PandaX-II experiment, Phys. Rev. Lett. 117 (2016) 121303 [arXiv:1607.07400] [INSPIRE].
  46. [46]
    XENON collaboration, Dark matter search results from a one ton-year exposure of XENON1T, Phys. Rev. Lett. 121 (2018) 111302 [arXiv:1805.12562] [INSPIRE].
  47. [47]
    G. Bélanger, F. Boudjema, A. Pukhov and A. Semenov, Dark matter direct detection rate in a generic model with MicrOMEGAs 2.2, Comput. Phys. Commun. 180 (2009) 747 [arXiv:0803.2360] [INSPIRE].
  48. [48]
    A. Djouadi, J.-L. Kneur and G. Moultaka, SuSpect: a fortran code for the supersymmetric and Higgs particle spectrum in the MSSM, Comput. Phys. Commun. 176 (2007) 426 [hep-ph/0211331] [INSPIRE].
  49. [49]
    A. Djouadi, M.M. Muhlleitner and M. Spira, Decays of supersymmetric particles: the program SUSY-HIT (SUspect-SdecaY-HDECAY-InTerface), Acta Phys. Polon. B 38 (2007) 635 [hep-ph/0609292] [INSPIRE].
  50. [50]
    Particle Data Group collaboration, Review of particle physics, Phys. Rev. D 98 (2018) 030001 [INSPIRE].
  51. [51]
    CMS collaboration, Search for new phenomena with the M T2 variable in the all-hadronic final state produced in proton-proton collisions at \( \sqrt{s} \) = 13 TeV, Eur. Phys. J. C 77 (2017) 710 [arXiv:1705.04650] [INSPIRE].
  52. [52]
    CMS collaboration, Search for direct production of supersymmetric partners of the top quark in the all-jets final state in proton-proton collisions at \( \sqrt{s} \) = 13 TeV, JHEP 10 (2017) 005 [arXiv:1707.03316] [INSPIRE].
  53. [53]
    CMS collaboration, Search for natural and split supersymmetry in proton-proton collisions at \( \sqrt{s} \) = 13 TeV in final states with jets and missing transverse momentum, JHEP 05 (2018) 025 [arXiv:1802.02110] [INSPIRE].
  54. [54]
    CMS collaboration, Search for the pair production of third-generation squarks with two-body decays to a bottom or charm quark and a neutralino in proton-proton collisions at \( \sqrt{s} \) = 13 TeV, Phys. Lett. B 778 (2018) 263 [arXiv:1707.07274] [INSPIRE].
  55. [55]
    H. Baer, V. Barger, P. Huang, A. Mustafayev and X. Tata, Radiative natural SUSY with a 125GeV Higgs boson, Phys. Rev. Lett. 109 (2012) 161802 [arXiv:1207.3343] [INSPIRE].ADSCrossRefGoogle Scholar
  56. [56]
    H. Baer, V. Barger, P. Huang, D. Mickelson, A. Mustafayev and X. Tata, Post-LHC7 fine-tuning in the minimal supergravity/CMSSM model with a 125 GeV Higgs boson, Phys. Rev. D 87 (2013) 035017 [arXiv:1210.3019] [INSPIRE].ADSGoogle Scholar

Copyright information

© The Author(s) 2019

Authors and Affiliations

  1. 1.Department of Chemistry and PhysicsLouisiana State UniversityShreveportU.S.A.
  2. 2.CAS Key Laboratory of Theoretical Physics, Institute of Theoretical PhysicsChinese Academy of SciencesBeijingP.R. China
  3. 3.School of Physical SciencesUniversity of Chinese Academy of SciencesBeijingP.R. China
  4. 4.George P. and Cynthia W. Mitchell Institute for Fundamental Physics and AstronomyTexas A&M UniversityCollege StationU.S.A.
  5. 5.Astroparticle Physics GroupHouston Advanced Research Center (HARC)WoodlandsU.S.A.
  6. 6.Academy of Athens, Division of Natural SciencesAthensGreece

Personalised recommendations