Following the recent T2K indication of a sizeable reactor angle, we present class models which fix θ13 while preserving trimaximal solar mixing. The are based on new type constrained sequential dominance involving vacuum alignments, along (1,2,0)T or (1,0,2)T directions in flavour space. We show that such alignments easily achieved using orthogonality, and may replace role subdominant flavon alignment (1,1,1)T dominance. In models, with normal hierarchical spectrum, angle is related to ratio...

Group theoretical factors from grand unified theory (GUT) symmetry breaking can lead to predictions for the ratios of quark and lepton masses (or Yukawa couplings) at unification scale. Because supersymmetric (SUSY) threshold corrections viability such depend strongly on SUSY parameters. For three common minimal scenarios with anomaly, gauge, gravity mediation we investigate which GUT scale ${m}_{e}/{m}_{d}$, ${m}_{\ensuremath{\mu}}/{m}_{s}$, ${y}_{\ensuremath{\tau}}/{y}_{b}$,...

We investigate the effect of supersymmetric (SUSY) threshold corrections on values running quark and charged lepton masses at grand unified theory (GUT) scale within large $\mathrm{tan}\ensuremath{\beta}$ regime minimal standard model. In addition to typically dominant SUSY QCD contributions for quarks, we also include electroweak quarks leptons show that they can have significant effects. provide GUT ranges Yukawa couplings as well ratios ${m}_{\ensuremath{\mu}}/{m}_{s}$, ${m}_{e}/{m}_{d}$,...

We present a SUSY $SU(5)\ifmmode\times\else\texttimes\fi{}{T}^{\ensuremath{'}}$ unified flavor model with type I seesaw mechanism of neutrino mass generation, which predicts the reactor angle to be ${\ensuremath{\theta}}_{13}\ensuremath{\approx}0.14$ close recent results from Daya Bay and RENO experiments. The also values solar atmospheric mixing angles, are compatible existing data. ${T}^{\ensuremath{'}}$ breaking leads tribimaximal in sector, is perturbed by sizeable corrections charged...

We analyse the interplay of generalised CP transformations and non-Abelian discrete group T ′ use semi-direct product G f = ⋊H CP, as family symmetry acting in lepton sector. The is shown to be spontaneously broken a geometrical manner. In resulting flavour model, naturally small Majorana neutrino masses for light active neutrinos are obtained through type I see-saw mechanism. known charged leptons, mixing angles two mass squared differences reproduced by model with good accuracy. allows...

We revisit a two right-handed neutrino model with texture zeros, namely an indirect based on ${A}_{4}$ the recently proposed new type of constrained sequential dominance (CSD2), involving vacuum alignments along $(0,1,\ensuremath{-}1{)}^{T}$ and $(1,0,2{)}^{T}$ directions in flavor space, which are proportional to Dirac mass matrix columns. In this paper we construct renormalizable unified ${A}_{4}\ifmmode\times\else\texttimes\fi{}SU(5)$ these lines show that, spontaneous $CP$ violation...

In this paper we study an SU(5) x A5 flavour model which exhibits a neutrino mass sum rule and golden ratio mixing in the sector is corrected from charged lepton Yukawa couplings. We give full renormalizable superpotential for breaks after integrating out heavy messenger fields minimising scalar potential. The allows both orderings but will show that inverted ordering not valid setup. For normal find lightest to have of about 10-50 meV, all leptonic angles agreement with experiment.

We propose a flavored $U(1)_{e\mu}$ neutrino mass and dark matter~(DM) model to explain the recent DArk Matter Particle Explorer (DAMPE) data, which feature an excess on cosmic ray electron plus positron flux around 1.4 TeV. Only first two lepton generations of Standard Model are charged under new gauge symmetry. A vector-like fermion $\psi$, is our DM candidate, annihilates into $e^{\pm}$ $\mu^{\pm}$ via boson $Z'$ exchange accounts for DAMPE excess. have found that data favors $\psi$...

We propose new predictions from grand unified theories (GUTs) [applicable to both supersymmetric (SUSY) and non-SUSY models] for the ratios of quark lepton Yukawa couplings. These arise splitting masses messenger fields GUT-scale operators by Clebsch-Gordan factors GUT symmetry breaking. This has effect that these enter inversely in predicted quark-lepton coupling ratios, leading possible predictions. systematically construct can be realized this way SU(5) GUTs Pati-Salam discuss model...

We discuss how the double missing partner mechanism solution to doublet-triplet splitting problem in four-dimensional supersymmetric SU(5) Grand Unified Theories (GUTs) can be combined with predictive models for quark-lepton Yukawa coupling ratios at GUT scale. It is argued that towards this goal a second breaking Higgs field adjoint representation very useful and we all possible renormalizable superpotentials two fields calculate constraints on scale effective triplet mass from two-loop...

The cosmic neutrino background is a key prediction of Big Bang cosmology which has not been observed yet. movement the earth through this bath creates force on pendulum, as if it were exposed to wind. We revise here estimates for resulting pendulum acceleration and compare theoretical sensitivity an experimental setup where position measured using current laser interferometer technology employed in gravitational wave detectors. discuss how significant improvement can be envisaged micro...

We propose a supersymmetric A4 x SU(5) model of quasi-degenerate neutrinos which predicts the effective neutrino mass m_ee relevant for neutrinoless double beta decay to be proportional scale, thereby allowing its determination approximately independently unknown Majorana phases. Such natural quasi-degeneracy is achieved by using (as an example non-Abelian family symmetry with real triplet representations) enforce type II seesaw contribution matrix identity. Tri-bimaximal mixing arises from...

We analyse the fine-tuning in Constrained Minimal Supersymmetric Standard Model (CMSSM) light of present and expected ATLAS CMS SUSY searches. Even with 10/fb data no discovery valid regions might remain less than 20. Moreover we investigate price GUT scale Yukawa coupling relations. Considering a 2$\sigma$ constraint for $(g-2)_\mu$ 30 yields an allowed range $y_\tau/y_b = [1.31,1.70]$, which points towards alternative prediction 3/2$. Relaxing to 5$\sigma$ extends possible region...

In this paper we discuss a minor modification of previous SU(5) x A5 flavour model which exhibits at leading order golden ratio mixing and sum rules for the heavy light neutrino masses. Although could predict all angles well it fails in generating sufficient large baryon asymmetry via leptogenesis mechanism. We repair deficit here, building aspects give analytical estimates generated before perform numerical parameter scan. Our setup has only few parameters lepton sector. This leads to...

Correlations between light neutrino observables are arguably the strongest predictions of lepton avour models based on (discrete) symmetries, except for very few cases which unambiguously predict full set leptonic mixing angles. A subclass these correlations mass sum rules, connect three (complex) eigenvalues among each other. This connection constrains both scale and Majorana phases, so that rules generically lead to a nonzero value lightest distinct e ective probed in neutrinoless double...

In analogy with the recently proposed lepton mixing sum rules, we derive quark rules for case of hierarchical mass matrices 1-3 texture zeros, in which separate up and down type angles are approximately zero, $V_{ub}$ is generated from $V_{cb}$ as a result 1-2 mixing. Using discuss phenomenological viability such textures, including to four show how right-angled unitarity triangle, i.e., $\alpha \approx 90^\circ$, can be accounted by remarkably simple scheme involving real apart single...

Neutrino mass sum rules are an important class of predictions in flavour models relating the Majorana phases to neutrino masses. This leads, for instance, enormous restrictions on effective as probed experiments neutrinoless double beta decay. While up now these have practically all cases been taken hold exactly, we will go here beyond that. After a discussion types corrections that could possibly appear and elucidating theory behind rules, estimate explicitly compute impact radiative...

We derive and discuss the solution of Boltzmann equations for leptogenesis in a phenomenologically viable SU(5)×A5 golden ratio flavour model proposed [1], [2]. The employs, particular, seesaw mechanism neutrino mass generation. find that results on baryon asymmetry Universe, obtained earlier [2] using approximate analytic expressions relevant CP violating efficiency factors, are correct, as was expected, up to 20–30%. phenomenological predictions low energy observables, derived values...

Neutrino mixing sum rules are common to a large class of models based on the (discrete) symmetry approach lepton flavour. In this neutrino matrix U is assumed have an underlying approximate form Ũν, which dictated by, or associated with, employed symmetry. such setup cosine Dirac CP-violating phase δ can be related three angles in terms rule depends Ũν. We consider five extensively discussed possible forms Ũν: i) bimaximal (BM) and ii) tri-bimaximal (TBM) forms, corresponding iii) golden...