SUSY meets her twin

Abstract

We investigate the general structure of mirror symmetry breaking in the Twin Higgs scenario. We show, using the IR effective theory, that a significant gain in fine tuning can be achieved if the symmetry is broken hardly. We emphasize that weakly coupled UV completions can naturally accommodate this scenario. We analyze SUSY UV completions and present a simple Twin SUSY model with a tuning of around 10% and colored superpartners as heavy as 2 TeV. The collider signatures of general Twin SUSY models are discussed with a focus on the extended Higgs sectors.

Supersymmetric D-term Twin Higgs

“…This result for fine-tuning in the F -term Twin Higgs model was obtained for µ = 500 GeV, m S = 1 TeV and m stop = 2 TeV and was confirmed recently in ref. [8]. However, we find that the fine-tuning in the F -term Twin Higgs model is even more severe due to the Higgs mixing with the singlet which gives a negative contribution to the Higgs mass.…”

“…Therefore, these models require some UV completions. Twin Higgs models have been embedded in supersymmetric (SUSY) [4,5,7,8] and composite Higgs [6,[9][10][11][12][13][14][15] models. In the present work we focus on SUSY UV completions.…”

“…On the other hand, the SU (4) breaking quartic coupling from the EW D-term, which contributes to the Higgs mass, is an increasing function of tan β, and hence a smaller tan β requires a larger stop mass. 3 As a result the 125 GeV Higgs mass is incompatible with a large SU(4) invariant quartic term 1 This irreducible tuning may be evaded by introducing hard Z2 breaking but explicit models of this type require total tuning of O(10) % anyway [8]. 2 Cosmological constraints on Twin Higgs models generically require non-negligible Higgs decays to mirror fermions [16].…”

“…One could also consider a hard Z 2 breaking quartic term which in our setup is subdominant, see ref. [8] for discussion of effects of hard Z 2 breaking. The vevs of the Higgs fields and the masses of them are given by…”

Minimal non-abelian supersymmetric Twin Higgs

“…Early realisations of SUSY UV completion of Twin Higgs scenario [14,15], which generate an SU(4) invariant quartic term with an F -term potential of a heavy singlet superfield, are not able to significantly reduce fine-tuning as compared to non-Twin SUSY models [35][36][37]. It was only very recently that SUSY Twin Higgs models were proposed in which tuning at the level of 10% is possible by introducing either hard Z 2 symmetry breaking in the F -term model [36] or a new U(1) X gauge symmetry whose D-term potential…”