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Related papers: Neutrino Masses from the Top Down

200 papers

The convex geometric framework of positivity bounds allows us to explore the ultraviolet (UV) states in new physics models from the bottom up. The UV states in three types of seesaw models for tiny Majorana neutrino masses, as irreducible…

High Energy Physics - Phenomenology · Physics 2022-12-26 Xu Li , Shun Zhou

In the last years we have learnt a lot about neutrino masses and mixings. Neutrinos are not all massless but their masses are very small. Probably masses are small because neutrinos are Majorana particles with masses inversely proportional…

High Energy Physics - Phenomenology · Physics 2011-11-29 Guido Altarelli

The unique dimension-$5$ effective operator, $LLHH$, known as the Weinberg operator, generates tiny Majorana masses for neutrinos after electroweak spontaneous symmetry breaking. If there are new scalar multiplets that take vacuum…

High Energy Physics - Phenomenology · Physics 2024-05-09 Alessio Giarnetti , Juan Herrero-Garcia , Simone Marciano , Davide Meloni , Drona Vatsyayan

Neutrino Majorana masses and mixings can be generated from a dimension-5 operator within the standard model particle content. After a review of the mechanism of radiative enhancement of the mixing angle in a two-neutrino case, we consider…

High Energy Physics - Phenomenology · Physics 2009-11-07 Gautam Bhattacharyya , Amitava Raychaudhuri , Arunansu Sil

This is a review article about neutrino mass models, particularly see-saw models involving three active neutrinos which are capable of describing both the atmospheric neutrino oscillation data, and the large mixing angle MSW solar solution,…

High Energy Physics - Phenomenology · Physics 2009-11-10 S. F. King

Neutrinos stand out among elementary particles through their unusually small masses. Various seesaw mechanisms attempt to explain this fact. In this work applying insights from matrix theory we are in a position to treat variants of seesaw…

High Energy Physics - Phenomenology · Physics 2020-09-04 Wojciech Flieger , Janusz Gluza

A new mechanism is proposed for generating neutrino masses radiatively through a non-minimal coupling to gravity of fermionic bilinears involving massive neutral fermions. Such coupling terms can arise in theories where the gravity sector…

High Energy Physics - Phenomenology · Physics 2008-11-26 Abhinav Gupta , Namit Mahajan , Amitabha Mukherjee

I discuss dynamical generation of neutrino masses in unconventional scenarios where the background space-time geometry plays a crucial role. I discuss two types of backgrounds: (i) Lorentz Violating and (ii) Geometries with Torsion. In the…

High Energy Physics - Phenomenology · Physics 2015-06-05 Nick E. Mavromatos

Restrictions on the neutrino masses and lepton mixing are reviewed. Solar, atmospheric and relic neutrinos give the indications of existence of nonzero neutrino masses and mixing. The data pick up two regions of mixing angles which are or…

High Energy Physics - Phenomenology · Physics 2009-09-25 Alexei Yu. Smirnov

A form of mixing matrix for three active and three sterile, conventional Majorana neutrinos is proposed. Its Majorana lefthanded part arises from the popular bimaximal mixing matrix for three active neutrinos that works satisfactorily in…

High Energy Physics - Phenomenology · Physics 2007-05-23 Wojciech Krolikowski

We propose a new mechanism where both Dirac masses for the charged-leptons and Majorana masses for neutrinos are generated via quantum levels. The charged-lepton masses are given by the vacuum expectation values (VEVs) of the Higgs doublet…

High Energy Physics - Phenomenology · Physics 2014-03-26 Hiroshi Okada , Kei Yagyu

It is argued that the quantum gravity attractions dynamically generate tiny degenerate Majorana masses for the neutrinos. The unequal masses of the charged leptons then induce a computable neutrino mass matrix with splittings and mixings…

High Energy Physics - Theory · Physics 2007-10-25 H. S. Sharatchandra

We study models of neutrino masses which naturally give rise to an inverted mass hierarchy and bi-maximal mixing. The models are based on the see-saw mechanism with three right-handed neutrinos, which generates a single mass term of the…

High Energy Physics - Phenomenology · Physics 2009-10-31 S. F. King , N. Nimai Singh

In the framework of the seesaw mechanism, and adopting a typical form for the Dirac neutrino mass matrix, we discuss the impact of minimal forms of the Majorana neutrino mass matrix. These matrices contain four or three texture zeros and…

High Energy Physics - Phenomenology · Physics 2009-11-10 D. Falcone

In this paper, we obtain the light neutrino masses and mixings consistent with the experiments, in the democratic texture approach. The essential ansatz is that $\nu_{Ri}$ are assumed to transform as "right-handed fields" $\bf 2_{R} +…

High Energy Physics - Phenomenology · Physics 2020-05-28 Masaki J. S. Yang

We demonstrate that under the "symmetric zero texture" with minimal Majorana mass matrix, neutrino masses and mixing angles are expressed in terms of up-quark masses, $m_t,m_c,m_u$. This provides interesting relations among neutrino mixing…

High Energy Physics - Phenomenology · Physics 2017-08-23 Masako Bando , Midori Obara

The radiative seesaw mechanism proposed recently is minimally extended to include supersymmetry in a specific model. Relevant related issues such as leptogenesis and dark matter are discussed.

High Energy Physics - Phenomenology · Physics 2008-11-26 Ernest Ma

We study the pseudo-Dirac mixing of left and right-handed neutrinos in the case where the Majorana masses M_L and M_R are small when compared with the Dirac mass, M_D. The light Majorana masses could be generated by a non-renormalizable…

High Energy Physics - Phenomenology · Physics 2011-07-19 K. R. S. Balaji , Anna Kalliomaki , Jukka Maalampi

If neutrino masses are obtained via the canonical seesaw mechanism, based on an underlying 2X2 mass matrix, unitarity violation of the neutrino mixing matrix is unavoidable, but its effect is extremely small. On the other hand, in the…

High Energy Physics - Phenomenology · Physics 2010-11-15 Ernest Ma

In this talk we assume the conventional see-saw mechanism, and contruct a hierarchical pattern of three active neutrinos with bi-maximal mixing. In order to enforce the hierarchy we use the single right handed neutrino dominance mechanism…

High Energy Physics - Phenomenology · Physics 2008-11-26 S. F. King