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LUO Min-Jie LIU Qiu-Yu 《理论物理通讯》2008,50(8):451-458
We consider that the Higgs triplet Yukawa coupling takes the Friedberg-Lee texture, and the Higgs doublet Yukawa coupling simply identifies with the diagonal Yutawa coupling of charged lepton in the context of left-right symmetric model. In this scenario, the phenomenology, including effective neutrino masses, mixings, and thermal flavor-dependent leptogenesis and lepton flavor violation decays are studied. We investigate the combined constrain of the parameters in this scenario and test its consistency with present data. 相似文献
3.
In this paper, we introduce leptogenesis via a varying Weinberg operator from a semi-classical perspective.This mechanism is motivated by the breaking of an underlying symmetry which triggers a phase transition that causes the coupling of the Weinberg operator to become dynamical. Consequently, a lepton anti-lepton asymmetry arises from the interference of the Weinberg operator at two different spacetime points. Using the semi-classical approach,we treat the Higgs as a background field and show that a reflection asymmetry between leptons and anti-leptons is generated in the vicinity of the bubble wall. We solve the equations of motion of the lepton and anti-lepton quasiparticles to obtain the final lepton asymmetry. 相似文献
4.
Werner Rodejohann 《Pramana》2009,72(1):217-227
The see-saw mechanism to generate small neutrino masses is reviewed. After summarizing our current knowledge about the low
energy neutrino mass matrix, we consider reconstructing the see-saw mechanism. Indirect tests of see-saw are leptogenesis
and lepton flavour violation in supersymmetric scenarios, which together with neutrino mass and mixing define the framework
of see-saw phenomenology. Several examples are given, both phenomenological and GUT-related.
相似文献
5.
Krzysztof Turzynski 《Czechoslovak Journal of Physics》2005,55(10):1193-1204
We analyze the predictions of the most general version of the supersymmetric minimal seesaw model with only two right-chiral
neutrinos, which are degenerate in masses at the scale of Grand Unification. We apply the renormalization group technique
to the running of the masses of the right-chiral neutrinos and the neutrino Yukawa couplings and find that thermal leptogenesis
can account for the observed baryon asymmetry of the Universe even with a low reheating temperature, allowing to overcome
the gravitino problem.
Presented at the XVI Indian Summer School “Understanding Neutrinos”, Prague, Czech Republic, September 8–13, 2004. 相似文献
6.
Sandhya Choubey D. Indumathi S. Agarwalla A. Bandyopadhyay G. Bhattacharyya E. J. Chun B. Dasgupta A. Dighe P. Ghoshal A. K. Giri S. Goswami M. Hirsch T. Kajita M. Kaplinghat H. S. Mani R. Mohanta M. V. N. Murthy S. Pakvasa M. K. Parida G. Rajasekaran S. Ray W. Rodejohann P. Roy S. Uma Sankar T. Schwetz N. Sinha 《Pramana》2009,72(1):269-275
This is the report of the neutrino physics working group at WHEPP-X. We summarize the problems selected and discussed at the
workshop and the papers which have resulted subsequently.
相似文献
7.
Silvia Pascoli 《Pramana》2006,67(4):665-680
Establishing CP-violation in the lepton sector is one of the most challenging future tasks in neutrino physics. The lepton
mixing matrix contains one Dirac phase and, if neutrinos are Majorana particles, two additional CP-violating phases. I will
review the main theoretical aspects of CP-violation in the lepton sector. Then, I will present the strategies for determining
the Dirac and the Majorana CP-violating phases in long-baseline and neutrinoless double beta decay experiments, respectively.
Leptonic CP-violation has received recently a lot of attention as it might be at the origin of the baryon asymmetry of the
Universe. Within the context of the see-saw mechanism, I will discuss the possible connection between the CP-violating phases
measurable at low energy with the ones entering in leptogenesis. 相似文献
8.
In this paper, proceeding from the relation between the Cardassian model and the accelerated expansion of the universe, adopting a parametric method which does not depend on a precise mechanism for gravitational baryo/leptogenesis and using the model parameter of CPT-violating interaction, we study the role of the modified Friedmann equation which plays a role in the matter asymmetry of the early epoch and the accelerated expansion of the present universe. Thus the appropriate Cardassian component in the radiation-dominated era or in the matter-dominated universe can be obtained. The results indicate that early CPT-violation is included in the Cardassian term. In the same way, the present Cardassian term that belongs to a quintessence-like model can drive the universe towards a flat, matter-dominated and accelerating expansion. 相似文献
9.
Jogesh C. Pati 《Pramana》2004,62(2):513-522
Evidence in favor of supersymmetric grand unification including that based on the observed family multiplet-structure, gauge
coupling unification, neutrino oscillations, baryogenesis, and certain intriguing features of quark-lepton masses and mixings
is noted. It is argued that attempts to understand (a) the tiny neutrino masses (especially Δm
2(v
2 – v3)), (b) the baryon asymmetry of the Universe (which seems to need leptogenesis), and (c) the observed features of fermion
masses such as the ratiom
b/mτ, the smallness ofV
cb and the maximality of
seem to select out the route to higher unification based on an effective string-unifiedG(224) =SU(2)L ×SU(2)R ×SU(2)c orSO(10)-symmetry that should be operative in 4D, as opposed to other alternatives. A predictiveSO(10)/G(224)-framework possessing supersymmetry is presented that successfully describes the masses and mixings of all fermions including
neutrinos. It also accounts for the observed baryon asymmetry of the Universe by utilizing the process of leptogenesis, which
is natural to this framework. It is argued that a conservative upper limit on the proton lifetime within thisSO(10)/G(224)-framework, which is so far most successful, is given by
x 1034 years. This in turn strongly suggests that an improvement in the current sensitivity by a factor of five to ten (compared
to SuperK) ought to reveal proton decay. Implications of this prediction for the next-generation nucleon decay and neutrino-detector
are noted. 相似文献
10.
In this study, we investigate the possibilities of generating baryon number asymmetry under thermal equilibrium within the frameworks of teleparallel and symmetric teleparallel gravities. Through the derivative couplings of the torsion scalar and the non-metricity scalar to baryons, baryon number asymmetry is produced in the radiation dominated epoch. For gravitational baryogenesis mechanisms in these two frameworks, the produced baryon-to-entropy ratio is too small to be consistent with observations. However, the gravitational leptogenesis models within both frameworks have the potential to explain the observed baryon-antibaryon asymmetry. 相似文献