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Related papers: Testing New TeV-scale Seesaw Mediators at the LHC

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In the type-II seesaw mechanism, the neutrino mass generation could be tested experimentally if the Higgs triplet is at the TeV scale and has a small cubic coupling to the standard model Higgs doublet. We show such small triplet-doublet…

High Energy Physics - Phenomenology · Physics 2020-01-15 Pei-Hong Gu

We study fermion masses and mixing angles, including the generation of a seesaw mechanism for the neutrinos, in extended technicolor (ETC) theories. We formulate an approach to these problems that relies on assigning right-handed $Q=-1/3$…

High Energy Physics - Phenomenology · Physics 2009-11-10 Thomas Appelquist , Maurizio Piai , Robert Shrock

Majorana neutrinos in the seesaw model can have sizable mixings through which they can be produced at the Large Hadron Collider (LHC) and show a remarkable Lepton Number Violating (LNV) signature. In this article we study the LNV decay of…

High Energy Physics - Phenomenology · Physics 2019-11-20 Gorazd Cvetic , Arindam Das , Sebastian Tapia , Jilberto Zamora-Saa

We systematically analyze the Dirac and the Majorana mass matrices in seesaw models with two heavy right-handed neutrinos. We perform thorough classification of the vanishing matrix elements which are compatible with the results from the…

High Energy Physics - Phenomenology · Physics 2009-02-20 Srubabati Goswami , Atsushi Watanabe

Existence of color sextet diquark Higgs fields with TeV masses will indicate a fundamentally different direction for unification than conventional grand unified theories. There is a class of partial unification models based on the gauge…

High Energy Physics - Phenomenology · Physics 2008-11-26 R. N. Mohapatra , Nobuchika Okada , Hai-Bo Yu

A search is performed for a heavy Majorana neutrino (N), produced by leptonic decay of a W boson propagator and decaying into a W boson and a lepton, with the CMS detector at the LHC. The signature used in this search consists of two…

High Energy Physics - Experiment · Physics 2019-01-25 CMS Collaboration

In this review, the seesaw mechanism for generating the mass of active light neutrinos (both Majorana and Dirac) is considered on the basis of effective field theory. In particular, we review certain models that extend the Standard Model by…

High Energy Physics - Phenomenology · Physics 2024-01-11 A. V. Borisov , A. P. Isaev

We propose a strategy for distinguishing the Dirac / Majorana character of heavy neutrinos with masses below the $W$ boson mass, using purely leptonic decays at the LHC. The strategy makes use of a forward-backward asymmetry of the opposite…

High Energy Physics - Phenomenology · Physics 2018-03-14 Carolina Arbelaéz , Claudio Dib , Iván Schmidt , Juan Carlos Vasquez

We consider the see-saw mechanism for hierarchical Dirac and Majorana neutrino mass matrices m_D and M_R, including the CP violating phases. Simple arguments about the structure of the neutrino mass matrix and the requirement of successful…

High Energy Physics - Phenomenology · Physics 2011-07-19 Werner Rodejohann

We analyse the effects of Dirac and Majorana neutrinos on leptonic decays of muon and tau leptons using the most general four-lepton effective interaction Hamiltonian of dimension six. We calculate the specific energy and angular…

High Energy Physics - Phenomenology · Physics 2023-01-20 Juan Manuel Márquez , Gabriel López Castro , Pablo Roig

The naturalness of electroweak scale in the models of type-I seesaw mechanism with ${\cal O}(1)$ Yukawa couplings requires TeV scale masses for the fermion singlets. In this case, the tiny neutrino masses have to arise from the…

High Energy Physics - Phenomenology · Physics 2017-06-27 Pratik Chattopadhyay , Ketan M. Patel

A new mechanism for generating neutrino masses without a high-energy mass scale is proposed. The mechanism needs a fundamental mass scale M in the 100-1000 TeV region and a minimal field content beyond the Standard Model one containing a…

High Energy Physics - Phenomenology · Physics 2007-05-23 Emilian Dudas , Carlos A. Savoy

We consider a scenario of Low Scale Seesaw where the masses of its heavy Majorana neutrinos are arranged in a pattern of three pairs of quasi degenerate ones, in the range of O(1-6 GeV). Since they can violate lepton number by two units,…

High Energy Physics - Phenomenology · Physics 2016-12-01 Gaston Moreno , Jilberto Zamora-Saa

We have recently proposed a simple SU(5) theory with an adjoint fermionic multiplet on top of the usual minimal spectrum. This leads to the hybrid scenario of both type I and type III seesaw and it predicts the existence of the fermionic…

High Energy Physics - Phenomenology · Physics 2008-11-26 Borut Bajc , Miha Nemevsek , Goran Senjanovic

We propose a viable theory based on the $SU(3)_C\times SU(3)_L\times U(1)_X$ gauge group supplemented by the $S_4$ discrete group together with other various symmetries, whose spontaneous breaking gives rise to the current SM fermion mass…

High Energy Physics - Phenomenology · Physics 2020-03-02 A. E. Cárcamo Hernández , Nicolás A. Pérez-Julve , Yocelyne Hidalgo Velásquez

We study the potential of testing the seesaw type I and III models at the LHeC, an e-p collision mode at the CERN collider. The e-p collision mode provides an excellent place to study lepton number violating process e^- p \to N j + X \to…

High Energy Physics - Phenomenology · Physics 2011-03-28 Liang Han , Xiao-Gang He , Ma Wen-Gan , Wang Shao-Ming , Zhang Ren-You

We establish a hybrid seesaw mechanism to explain small neutrino masses and predict cold dark matter candidate in the context of the B-L gauge symmetry extension of the Standard Model. In this model a new scalar doublet and two new fermion…

High Energy Physics - Phenomenology · Physics 2015-03-13 Tong Li , Wei Chao

In the simple model of neutrino texture presented in this paper, the Majorana left-handed mass matrix is zero, the Majorana righthanded mass matrix - diagonal and degenerate, and the Dirac mass matrix has a hierarchical structure, deformed…

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

We propose an extended 2HDM with $Q_6\times Z_4\times Z_2$ symmetry that can successfully accommodate the SM fermion mass and mixing hierarchy. The tiny masses of the active neutrinos are generated from a type-I seesaw mechanism mediated by…

High Energy Physics - Phenomenology · Physics 2024-10-30 V. V. Vien , H. N. Long , A. E. Cárcamo Hernández , Juan Marchant González

We explore an intriguing possibility to test the type-II seesaw mechanism of neutrino mass generation at the Large Hadron Collider (LHC). We show that the lepton-number-violating signatures of heavy Majorana neutrinos N_i (for i=1, 2, 3)…

High Energy Physics - Phenomenology · Physics 2008-11-26 Wei Chao , Zong-Guo Si , Zhi-zhong Xing , Shun Zhou