Coupling Supersymmetric Nonlinear Sigma Models to Supergravity

We study the phenomenological consequences of the supersymmetric (SUSY) E 7 /SU (5)× U (1) 3 non-linear sigma model coupled to supergravity, where the three generations of quark and lepton chiral multiplets appear as (pseudo) Nambu Goldstone (NG) multiplets, that is, the origin of the three families is explained. To break SUSY, we introduce a SUSY breaking field charged under some symmetry avoiding the Polonyi problem. The gaugino mass spectrum is almost uniquely determined when one requires the electroweak vacuum to be (meta)stable: it would be a miracle that the mass difference between the bino and wino turns out to be within O(1)% at the low energy. Thus, a bino-wino coannihilation is naturally predicted, which can explain the correct relic abundance of dark matter. Moreover, we find that the bottom-tau Yukawa couplings and the gauge couplings are unified up to O(1)% in most of the viable region. This scenario can be fully tested at the LHC and future collider experiments since the gauginos and some of the pseudo-NG bosons are light. An axion-like multiplet, which can be identified with the QCD axion, is also predicted.

Section: Review On Nls Modelmentioning

confidence: 99%

Bino-wino coannihilation as a prediction in the E7 unification of families

Yanagida

Yin

Yokozaki

2019

“…The 3 ) model has been investigated by many authors from various points of view [88][89][90][91][92][93][94][95][96][97][98][99]. 5 3 F-theory/heterotic duality, string junctions and the correspondence to homogeneous Kähler manifolds…”

Section: Jhep07(2014)018mentioning

confidence: 99%

F-theory family unification

Mizoguchi

2014

We propose a new geometric mechanism for naturally realizing unparallel three families of flavors in string theory, using the framework of F-theory. We consider a set of coalesced local 7-branes of a particular Kodaira singularity type and allow some of the branes to bend and separate from the rest, so that they meet only at an intersection point. Such a local configuration can preserve supersymmetry. Its matter spectrum is investigated by studying string junctions near the intersection, and shown to coincide, after an orbifold projection, with that of a supersymmetric coset sigma model whose target space is a homogeneous Kähler manifold associated with a corresponding painted Dynkin diagram. In particular, if one starts from the E 7 singularity, one obtains the E 7 /(SU(5) × U(1) 3 ) model yielding precisely three generations with an unparallel family structure. Possible applications to string phenomenology are also discussed.

“…It has been shown that if one eliminates the U(1) 2 in the unbroken subgroup one can couple the non-linear sigma model to supergravity without any explicit breaking of the E7 [7]. We will discuss the E7 model in a separate paper.…”

Section: An Example Of a Non-compact Manifold For The First And Seconmentioning

confidence: 99%

“…Unfortunately, it became known that the pure realization cannot be coupled to supergravity [4]. However, it has been recently pointed out that a hybrid realization with some doubled and some non-doubled NG multiplets does not suffer from this inconsistency [7]. We will therefore search for a hybrid non-linear sigma model that contains two generations of quarks and leptons as NG chiral multiplets.…”

Section: Jhep01(2011)131mentioning

confidence: 99%

Testing the Nambu-Goldstone hypothesis for quarks and leptons at the LHC

Mandal

Nojiri

Sudano

et al. 2011

The hierarchy of the Yukawa couplings is an outstanding problem of the standard model. We present a class of models in which the first and second generation fermions are SUSY partners of pseudo-Nambu-Goldstone bosons that parameterize a non-compact Kähler manifold, explaining the small values of these fermion masses relative to those of the third generation. We also provide an example of such a model. We find that various regions of the parameter space in this scenario can give the correct dark matter abundance, and that nearly all of these regions evade other phenomenological constraints. We show that for mg ∼ 700 GeV, model points from these regions can be easily distinguished from other mSUGRA points at the LHC with only 7 fb −1 of integrated luminosity at 14 TeV. The most striking signatures are a dearth of b-and τ -jets, a great number of multi-lepton events, and either an "inverted" slepton mass hierarchy, narrowed slepton mass hierarchy, or characteristic small-µ spectrum.