Fermionic UV completions of composite Higgs models

Abstract

Abstract:We classify the four-dimensional purely fermionic gauge theories that give a UV completion of composite Higgs models. Our analysis is at the group theoretical level, addressing the necessary (but not sufficient) conditions for the viability of these models, such as the existence of top partners and custodial symmetry. The minimal cosets arising are those of type SU(5)/SO(5) and SU(4)/Sp(4). We list all the possible "hyper-color" groups allowed and point out the simplest and most promising ones.

Gauge theories of partial compositeness: scenarios for Run-II of the LHC

“…The recent model building activities try to combine the two. Few explicit proposals have been made so far: [11,12] and [13] and a partial classification of the available options was made in [14]. (For earlier attempts using supersymmetry, see [15,16].…”

“…These are listed in appendix A for completeness. More details can be found in [14]. Table 1 also shows a "ubiquitous" non-anomalous U(1) u factor arsing from the spontaneous breaking of the G HC -anomaly-free abelian chiral symmetry.…”

“…Comparing with [14] we have removed a few models that do not seem promising. Some are based on spinorial irreps of the orthogonal group for which, as discussed in [14], the MAC hypothesis leads to the wrong symmetry breaking pattern.…”

“…Some are based on spinorial irreps of the orthogonal group for which, as discussed in [14], the MAC hypothesis leads to the wrong symmetry breaking pattern. Others are those having baryons of type χψχ with ψ in a complex irrep.…”

Fundamental partial compositeness

“…In fact, by construction the new composite techni-baryons have mass dimensions close to the minimum required of 5/2. Because any purely fermionic extension [27][28][29][30] is required to have composite baryons with dimensions close to 5/2, these baryons would presumably behave as if they were made by a fermion and a composite scalar similar to ours (see also [31] for a supersymmetric realization). The technicolor group is indicated by G TC , which can be either SU(N ), SO(N ) or Sp(N ) with vectorial techni-fermions and techni-scalars.…”