Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new user$0 ubetabeta$ in left-right theories with Higgs doublets and gauge coupling unification
54
0
0.0
(
0
)
Ask ChatGPT about the research
No Arabic abstract
We consider a version of Left-Right Symmetric Model in which the scalar sector consists of a Higgs bidoublet ($Phi$) with $B-L=0$, Higgs doublets ($H_{L,R}$) with $B-L=1$ and a charged scalar ($delta^+$) with $B-L=2$ leading to radiatively generated Majorana masses for neutrinos and thereby, leads to new physics contributions to neutrinoless double beta decay ($0 u beta beta$). We show that such a novel framework can be embedded in a non-SUSY $SO(10)$ GUT leading to successful gauge coupling unification at around $10^{16}$ GeV with the scale of left-right symmetry breaking around $10^{10}$ GeV. The model can also be extended to have left-right symmetry breaking at TeV scale, enabling detection of $W_R, Z_R$ bosons in LHC and future collider searches. In the context of neutrinoless double beta decay, this model can saturate the present bound from GERDA and KamLAND-Zen experiments. Also, we briefly explain how keV-MeV range RH neutrino arising from our model can saturate various astrophysical and cosmological constraints and can be considered as warm Dark Matter (DM) candidate to address various cosmological issues. We also discuss on left-right theories with Higgs doublets without having scalar bidoublet leading to fermion masses and mixings by inclusion of vector like fermions.
rate research
Read More
We investigate the possibility of neutrinoless double beta decay ($0 ubetabeta$) and leptogenesis within the Alternative Left-Right Model (ALRM). Unlike the usual left-right symmetric model, ALRM features a Majorana right-handed neutrino which does not carry any charge. Further, in this picture the down-type quark and the charged leptons receive mass through the additional left-handed scalar field, rather than the usual doublet. Together, these features conspire to generate significant contributions to the $0 ubetabeta$ through vector-scalar ($WH$) mediation. For moderate masses of the relevant charged Higgs boson ($M_{H_1^pm}sim 200$ GeV), the half-life of $T_{frac{1}{2}}^{WH}$ is $sim 3times 10^{26}~{rm yrs}$ for both the case of $^{76}$Ge and $^{136}$Xe, well within the sensitivity expected by future experiments. Invoking the resonant leptogenesis, CP violation arising from the right-handed neutrino decay could be the required order to generate the correct baryogenesis, $epsilonsim 10^{-6}$, for small Dirac phases and without any fine tuning.
We consider the triple coupling of the Higgs boson in the context of the gauge-Higgs unification scenario. We show that the triple coupling of the Higgs boson in this scenario generically deviates from SM prediction since the Higgs potential in this scenario has a periodicity. We calculate the coupling in the five-dimensional $SU(3)$ x $U(1)_X$ gauge-Higgs unification model and obtain 70% deviation from the SM prediction.
The electroweak phase transition in GUT inspired $SO(5) times U(1) times SU(3)$ gauge-Higgs unification is shown to be of weakly first-order and occurs at $T = T_c^{ rm EW} sim 163 ,$GeV, which is very similar to the behavior in the standard model in perturbation theory. There appears a new phase at higher temperature. $SU(2)_L times U(1)_Y$ ($ theta_H=0$) and $SU(2)_R times U(1)_{Y}$ ($ theta_H= pi$) phases become almost degenerate above $T sim m_{rm KK}$ where $m_{rm KK}$ is the Kaluza-Klein mass scale typically around 13TeV and $theta_H$ is the Aharonov-Bohm phase along the fifth dimension. The two phases become degenerate at $T = T_c^{rm LR} sim m_{rm KK}$. As the temperature drops in the evolution of the early universe the $SU(2)_R times U(1)_{Y}$ phase becomes unstable. The tunneling rate from the $SU(2)_R times U(1)_{Y}$ phase to the $SU(2)_L times U(1)_Y$ phase becomes sizable and a first-order phase transition takes place at $T=2.5 sim 2.6,$TeV. It is shown that the $W$ boson, $Z$ boson and photon, with $theta_H$ varying from 0 to $pi$, are transformed to gauge bosons in the $SU(2)_R times U(1)_{Y}$ phase. Gauge couplings and wave functions of quarks, leptons and dark fermions in the $SU(2)_R times U(1)_{Y}$ phase are determined.
The recent diphoton excess signal at an invariant mass of 750 GeV can be interpreted in the framework of left-right symmetric models with additional scalar singlets and vector-like fermions. We propose a minimal scenario for such a purpose. Extending the LRSM framework to include these new vector-like fermionic fields, on the other hand, results in interesting phenomenological implications for the LRSM fermion masses and mixing. Furthermore, existence of such vector-like fermions can also have interesting implications for baryogenesis and the dark matter sector. The introduction of a real bi-triplet scalar which contains a potential DM candidate will allow the gauge couplings to unify at $approx 10^{17.7}$ GeV.
Given the tremendous phenomenological success of the Standard Model (SM) framework, it becomes increasingly important to understand to what extent its specific structure dynamically emerges from unification principles. In this study, we present a novel supersymmetric (SUSY) Grand Unification model based upon gauge trinification $[mathrm{SU}(3)]^3$ symmetry and a local $mathrm{SU}(2)_{mathrm{F}} times mathrm{U}(1)_{mathrm{F}}$ family symmetry. This framework is inspired by $mathrm{E}_8 to mathrm{E}_6times mathrm{SU}(2)_{mathrm{F}} times mathrm{U}(1)_{mathrm{F}}$ orbifold reduction pattern, with subsequent $mathrm{E}_6to [mathrm{SU}(3)]^3$ symmetry breaking step. In this framework, higher-dimensional operators of $mathrm{E}_6$ induce the threshold corrections in the gauge and Yukawa interactions leading, in particular, to only two distinct Yukawa couplings in the fundamental sector of the resulting $[mathrm{SU}(3)]^3times mathrm{SU}(2)_{mathrm{F}} times mathrm{U}(1)_{mathrm{F}}$ Lagrangian. Among the appealing features emergent in this framework are the Higgs-matter unification and a unique minimal three Higgs doublet scalar sector at the electroweak scale as well as tree-level hierarchies in the light fermion spectra consistent with those observed in nature. In addition, our framework reveals a variety of prospects for New Physics searches at the LHC and future colliders such as vector-like fermions, as well as rich scalar, gauge and neutrino sectors.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
