Matter parity violating dark matter decay in minimal SO(10), unification, vacuum stability and verifiable proton decay

Abstract

In direct breaking of non-supersymmetric SO(10) to the standard model, we investigate the possibility that dark matter (DM) decaying through its mixing with right-handed neutrino (RHν) produces high energy IceCube neutrinos having type-I seesaw masses. Instead of one universal mixing and one common heavy RHν mass proposed in a recent standard model extension, we find that underlying quark-lepton symmetry resulting in naturally hierarchical RHν masses predict a separate mixing with each of them. We determine these mixings from the seesaw prediction of the DM decay rates into the light neutrino flavors. We further show that these mixings originate from Planck-scale assisted spontaneously broken matter parity needed to resolve the associated cosmological domain wall problem. This leads to the prediction of a new LHC accessible matter-parity odd Higgs scalar which also completes vacuum stability in the Higgs potential for its mass M χ S 177 GeV. We have also discussed realization of relic density of decaying dark matter in relation to flux of IceCube neutrinos. Two separate minimal SO(10) models are further noted to predict such dark matter dynamics where a single scalar submultiplet from 126 † H or 210 H of intermediate mass achieves precision gauge coupling unification. Despite the presence of two large Higgs representations and the fermionic dark matter host, 45 F , experimentally accessible proton lifetimes are also predicted with reduced uncertainties. †

A minimal non-supersymmetric SO(10) model with Peccei–Quinn symmetry

“…The proton lifetime τ p is directly related to the GUT scale, M GUT . The most constraining decay channel is via the dimension-six operator for p → e + π 0 and an approximate relation for τ p is given by [31,32]…”

High Scale Type-II Seesaw, Dominant Double Beta Decay within Cosmological Bound and LFV Decays in SU(‎5)

“…There is a possibility that such TeV scale QD masses while maintaining observable predictions on LFV decays can effectively generate baryon asymetry of the universe via resonant leptogenesis [128]. A scalar singlet DM can be easily accommodated as discussed in [129,168,169] while resolving the issue of vacuum stability. Irrespective of scalar DM, the model can also accommodate a Majorana fermion singlet dark matter [170] which can emerge from the additional fermionic representation 24 F ⊂ SU (5) .…”

Triplet leptogenesis, type-II seesaw dominance, intrinsic dark matter, vacuum stability and proton decay in minimal SO(10) breakings

“…However, in the absence of any experimental evidence of SUSY, very recently non-SUSY SO (10) has been in the spot light because of its inherent and intrinsic capability to predict DM candidates and their stability. In particular, an intrinsic gauged discrete symmetry [85], surviving as matter parity in SO (10) breakings [86][87][88][89][90][91][92][93][94][95][96][97][98][99][100][101][102][103]…”

“…has been found to stabilise the non-standard scalars and fermions which are also predicted to originate intrinsically from this non-SUSY GUT representations as possible DM candidates leading to a number of attractive predictions [86][87][88][89][90][91][92][93][94][95][96][97][98][99][100][101][102][103]. It is quite interesting to note that the matter parity conservation down to low energies naturally emerges whenever the popular Higgs representation 126 H is used to break the underlying U(1) B−L gauge symmetry and 10 H is used to break the electroweak symmetry materialising in type-I⊕type-II seesaw JCAP01(2020)049…”

“…• Precision coupling unification ensured by the presence of a single nonstandard scalar/ fermionic multiplet of intermediate mass ∼ 10 9.2 − 10 10. 4 GeV [88,103] and type-II dominance ensured by higher scale insertion of a complete 15 H ⊂ SU(5) at M ∆ with much larger SO (10) unification scale, M SO (10) M SU(5) > M ∆ .…”