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

200 papers

We present a search strategy for both Dirac and Majorana sterile neutrinos from the purely leptonic decays of $W^\pm \to e^\pm e^\pm \mu^\mp \nu$ and $\mu^\pm \mu^\pm e^\mp \nu$ at the 14 TeV LHC. The discovery and exclusion limits for…

High Energy Physics - Phenomenology · Physics 2017-11-06 Claudio O. Dib , C. S. Kim , Kechen Wang

There exists a generic minimal tree-level diagram, with two external scalars and a heavy intermediate fermion, that can generate naturally small neutrino masses via a seesaw. This diagram has a mass insertion on the internal fermion line,…

High Energy Physics - Phenomenology · Physics 2013-07-30 Kristian L. McDonald

Lepton flavor violating decays $\ell_{\alpha} \to \ell_{\beta} \gamma$, being forbidden in the Standard Model framework, provide a sensitive probe for new physics. We study these processes in a seesaw variant in which small neutrino masses…

High Energy Physics - Phenomenology · Physics 2025-10-29 Enrique Ramírez , Héctor Novales-Sánchez , Humberto Vázquez-Castro , Mónica Salinas

We present a new parametrization of the minimal seesaw model, expressing the heavy-singlet neutrino Dirac Yukawa couplings $(Y_\nu)_{ij}$ and Majorana masses $M_{N_i}$ in terms of effective light-neutrino observables and an auxiliary…

High Energy Physics - Phenomenology · Physics 2009-09-11 John Ellis , Junji Hisano , Martti Raidal , Yasuhiro Shimizu

A natural extension of the standard $SU(2)_{\rm L} \times U(1)_{\rm Y}$ gauge model to accommodate massive neutrinos is to introduce one Higgs triplet and three right-handed Majorana neutrinos, leading to a $6\times 6$ neutrino mass matrix…

High Energy Physics - Phenomenology · Physics 2008-11-26 Wei Chao , Shu Luo , Zhi-zhong Xing , Shun Zhou

If neutrino masses are realized through the see-saw mechanism, can the right-handed neutrinos be produced and detected at present and future colliders? The answer is negative in the most popular see-saw scenarios for the simple reason that…

High Energy Physics - Phenomenology · Physics 2008-11-26 P. Q. Hung

Many extensions of the Standard Model of particle physics contain new electrically-neutral fermions. Should one of these particles be discovered, questions will naturally arise regarding its nature. For instance: is it a self-conjugate…

High Energy Physics - Phenomenology · Physics 2022-02-02 André de Gouvêa , Patrick J. Fox , Boris J. Kayser , Kevin J. Kelly

A search for heavy Majorana neutrinos in events containing a pair of high-$p_{\mathrm{T}}$ leptons of the same charge and high-$p_{\mathrm{T}}$ jets is presented. The search uses $20.3 \mathrm{fb}^{-1}$ of $pp$ collision data collected with…

High Energy Physics - Experiment · Physics 2015-08-14 ATLAS Collaboration

We propose a new model where the Dirac mass term for neutrinos, the Majorana mass term for right-handed neutrinos, and the other new fermion masses arise via the spontaneous breakdown of the $U(1)_{B-L}$ gauge symmetry. The anomaly-free…

High Energy Physics - Phenomenology · Physics 2014-07-10 Shinya Kanemura , Toshinori Matsui , Hiroaki Sugiyama

On fitting the type II seesaw mechanism into the type I seesaw mechanism, we obtain a formula to the neutrino masses which get suppressed by high-scale $M^3$ in its denominator. As a result, light neutrinos are naturally obtained with new…

High Energy Physics - Phenomenology · Physics 2010-04-30 D. Cogollo , H. Diniz , C. A. de S. Pires

We study a multi-localization model for charged leptons and neutrinos, including the possibility of a see-saw mechanism. This framework offers the opportunity to allow for realistic solutions in a consistent model without fine-tuning of…

High Energy Physics - Phenomenology · Physics 2009-11-10 J. -M. Frere , G. Moreau , E. Nezri

We consider the TeV scale left-right symmetric theory which can accommodate low scale seesaw mechanisms consistent with neutrino oscillation data and find new physics contributions to neutrinoless double beta decay. The model facilitates…

High Energy Physics - Phenomenology · Physics 2016-12-26 Prativa Pritimita , Nitali Dash , Sudhanwa Patra

We propose an extension of the standard model with a B-L global symmetry that is broken softly at the TeV scale. The neutrinos acquire masses through a type-II seesaw while the lepton (L) asymmetry arises in the {\it singlet sector} but…

High Energy Physics - Phenomenology · Physics 2010-05-27 John McDonald , Narendra Sahu , Utpal Sarkar

Within the framework of a Beyond Standard Model (BSM) with a local $SU(3)$ family symmetry, we report an updated fit of parameters which account for the known spectrum of quarks and charged lepton masses and the quark mixing in a $4\times…

High Energy Physics - Phenomenology · Physics 2016-02-29 Albino Hernandez-Galeana

The Majorana nature of neutrinos may only be experimentally verified via lepton-number violating processes involving charged leptons. We explore the $\Delta L=2$ like-sign dilepton production at hadron colliders to search for signals of…

High Energy Physics - Phenomenology · Physics 2008-11-26 Tao Han , Bin Zhang

An extension of the Standard Model (SM) is studied in which two right-handed (RH) neutrinos per generation are incorporated, but considering the hypothesis of the symmetry of lepton and quark contents in order to deprive the number of RH…

High Energy Physics - Phenomenology · Physics 2015-01-13 Ernesto A. Matute

We explore the connection between low-scale CP-violating Dirac phase~$(\delta)$ and high-scale leptogenesis in a Left-Right Symmetric Model (LRSM) with scalar bidoublet and doublets. The fermion sector of the model is extended with one…

High Energy Physics - Phenomenology · Physics 2024-03-11 Utkarsh Patel , Pratik Adarsh , Sudhanwa Patra , Purushottam Sahu

We study the possibility to test the Type I seesaw mechanism for neutrino masses at the CERN Large Hadron Collider. The inclusion of three generations of right-handed neutrinos (N_i) provides an attractive option of gauging the B-L…

High Energy Physics - Phenomenology · Physics 2009-10-29 Pavel Fileviez Perez , Tao Han , Tong Li

Assuming the seesaw mechanism for hierarchical neutrino masses, we calculate the heavy neutrino masses under the hypotheses that the mixing in the Dirac leptonic sector is similar to the quark mixing ($V_D \sim V_{CKM}$) and that $M_{\nu}…

High Energy Physics - Phenomenology · Physics 2009-10-31 D. Falcone

We construct a model realizing the inverse seesaw mechanism. The model has two types of gauge singlet fermions in addition to right-handed neutrinos. A required Majorana mass scale (keV scale) for generating the light active neutrino mass…

High Energy Physics - Phenomenology · Physics 2015-11-30 Mayumi Aoki , Naoyuki Haba , Ryo Takahashi