ترغب بنشر مسار تعليمي؟ اضغط هنا

Lepton flavor violation from SUSY with non-universal scalars

86   0   0.0 ( 0 )
 نشر من قبل Hasan Serce
 تاريخ النشر 2019
  مجال البحث
والبحث باللغة English




اسأل ChatGPT حول البحث

Right-handed neutrinos in supersymmetric models can act as the source of lepton flavor violation (LFV). We present experimental implications of lepton flavor-violating processes within a supersymmetric type-I seesaw framework in the three-extra-parameter non-universal Higgs model (NUHM3) for large (PMNS-like) and small (CKM-like) Yukawa mixing scenarios. We highlight LFV predictions for the natural (low $Delta_{rm EW}$) portion of parameter space. Our numerical analysis includes full 2-loop renormalization group running effects for the three neutrino masses and mass matrices. We show the projected discovery reach of various LFV experiments ($textit{i.e.}$ Mu2e, Mu3e, MEG-II, Belle-II), and specify regions that have already been excluded by the LHC searches. Our results depend strongly on whether one has a normal sneutrino hierarchy (NSH) or an inverted sneutrino hierarchy (ISH). Natural SUSY with a NSH is already excluded by MEG-2013 results while large portions of ISH have been or will soon be tested. However, LFV processes from natural SUSY with small Yukawa mixing and an ISH seem below any projected sensitivities. A substantial amount of the remaining parameter space of models with large PMNS-like sneutrino mixing will be probed by Mu2e and MEG-II experiments whereas small, CKM-like Yukawa mixing predicts LFV decays which can hide from LFV experiments.


قيم البحث

اقرأ أيضاً

We analyze the phenomenological consequences of embedding a flavor symmetry based on the groups $A_5$ and CP in a supersymmetric framework. We concentrate on the leptonic sector, where two different residual symmetries are assumed to be conserved at LO for charged and neutral leptons. All possible realizations to generate neutrino masses at tree level are investigated. Sizable flavor violating effects in the charged lepton sector are unavoidable due to the non-universality of soft-breaking terms determined by the symmetry. We derive testable predictions for the neutrino spectrum, lepton mixing and flavor changing processes with non-trivial relations among observables.
We show that new physics models without new flavor violating interactions can explain the recent anomalies in the $bto sell^+ell^-$ transitions. The $bto sell^+ell^-$ arises from a $Z$ penguin which automatically predicts the $V-A$ structure for the quark currents in the effective operators. This framework can be realized either in a renormalizable $U(1)$ setup or be due to new strongly interacting dynamics. The di-muon resonance searches at the LHC are becoming sensitive to this scenario since the $Z$ is relatively light, and could well be discovered in future searches by ATLAS and CMS.
Flavor symmetric model is one of the attractive Beyond Standard Models (BSMs) to reveal the flavor structure of the Standard Model (SM). A lot of efforts have been put into the model building and we find many kinds of flavor symmetries and setups are able to explain the observed fermion mass matrices. In this paper, we look for common predictions of physical observables among the ones in flavor symmetric models, and try to understand how to test flavor symmetry in experiments. Especially, we focus on the BSMs for leptons with extra Higgs $SU(2)_L$ doublets charged under flavor symmetry. In many flavor models for leptons, remnant symmetry is partially respected after the flavor symmetry breaking, and it controls well the Flavor Changing Neutral Currents (FCNCs) and suggests some crucial predictions against the flavor changing process, although the remnant symmetry is not respected in the full lagrangian. In fact, we see that $tau^- to e^+ mu^- mu^-$ $( mu^+ e^- e^-)$ and $e^+ e^- to tau^+tau^-$ $(mu^-mu^+)$ processes are the most important in the flavor models that the extra Higgs doublets belong to triplet representation of flavor symmetry. For instance, the stringent constraint from the $mu to e gamma$ process could be evaded according to the partial remnant symmetry. We also investigate the breaking effect of the remnant symmetry mediated by the Higgs scalars, and investigate the constraints from the flavor physics: the flavor violating $tau$ and $mu$ decays, the electric dipole moments, and the muon anomalous magnetic moment. We also discuss the correlation between FCNCs and nonzero $theta_{13}$, and point out the physical observables in the charged lepton sector to test the BSMs for the neutrino mixing.
Till today lepton flavor violation has not been observed in processes involving charged leptons. Hence, a search for it is under hot pursuit both in theories and experiments. In our current work, we investigate the rates of rare decay processes such as $tau rightarrow mu gamma$ in SU(5) SUSY GUT and found that it satisfies the current bound and is one order below the projected sensitivity. This gives a corroborative argument for the influence of the large top-Yukawa coupling at the GUT scale ($lambda_{tG}$) on flavor violating decay rates of leptons which are investigable at low energy electroweak scale $M_Z$. Secondly, we discuss the decay rates of $mu rightarrow e gamma$ & $tau rightarrow mu gamma$ in MSSM with added right handed neutrino superfields. From this, we set bounds on $tan beta$ and further, we investigate the mass of $tilde{chi}^0 _1$, the LSP, using the rates of LFV decays. In the calculations, the latest updated data from LHC, neutrino oscillation experiments and constraints on branching ratios from the MEG experiment have been used.
168 - E. Arganda , M.J. Herrero 2007
Here we update the predictions for lepton flavour violating tau and muon decays, $l_j to l_i gamma$, $l_j to 3 l_i$, and $mu-e$ conversion in nuclei. We work within a SUSY-seesaw context where the particle content of the Minimal Supersymmetric Standa rd Model is extended by three right handed neutrinos plus their corresponding SUSY partners, and where a seesaw mechanism for neutrino mass generation is implemented. Two different scenarios with either universal or non-universal soft supersymmetry breaking Higgs masses at the gauge coupling unification scale are considered. After comparing the predictions with present experimental bounds and future sensitivities, the most promising processes are particularly emphasised.
التعليقات
جاري جلب التعليقات جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
mircosoft-partner

هل ترغب بارسال اشعارات عن اخر التحديثات في شمرا-اكاديميا