A Flavour-Symmetric Perspective on Neutrino Mixing
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Building the Full Pontecorvo-Maki-Nakagawa-Sakata Matrix from Six Independent Majorana-Type Phases
PHYSICAL REVIEW D 79, 013001 (2009) Building the full Pontecorvo-Maki-Nakagawa-Sakata matrix from six independent Majorana-type phases Gustavo C. Branco1,2,* and M. N. Rebelo1,3,4,† 1Departamento de Fı´sica and Centro de Fı´sica Teo´rica de Partı´culas (CFTP), Instituto Superior Te´cnico (IST), Av. Rovisco Pais, 1049-001 Lisboa, Portugal 2Departament de Fı´sica Teo`rica and IFIC, Universitat de Vale`ncia-CSIC, E-46100, Burjassot, Spain 3CERN, Department of Physics, Theory Unit, CH-1211, Geneva 23, Switzerland 4NORDITA, Roslagstullsbacken 23, SE-10691, Stockholm, Sweden (Received 6 October 2008; published 7 January 2009) In the framework of three light Majorana neutrinos, we show how to reconstruct, through the use of 3 Â 3 unitarity, the full PMNS matrix from six independent Majorana-type phases. In particular, we express the strength of Dirac-type CP violation in terms of these Majorana-type phases by writing the area of the unitarity triangles in terms of these phases. We also study how these six Majorana phases appear in CP-odd weak-basis invariants as well as in leptonic asymmetries relevant for flavored leptogenesis. DOI: 10.1103/PhysRevD.79.013001 PACS numbers: 14.60.Pq, 11.30.Er independent parameters. It should be emphasized that I. INTRODUCTION these Majorana phases are related to but do not coincide The discovery of neutrino oscillations [1] providing with the above defined Majorana-type phases. The crucial evidence for nonvanishing neutrino masses and leptonic point is that Majorana-type phases are rephasing invariants mixing, is one of the most exciting recent developments in which are measurable quantities and do not depend on any particle physics. -
Neutrino Masses and Oscillations in Theories Beyond the Standard Model
HELSINKI INSTITUTE OF PHYSICS INTERNAL REPORT SERIES HIP-2018-02 Neutrino masses and oscillations in theories beyond the Standard Model By TIMO J. KÄRKKÄINEN Helsinki Institute of Physics and Department of Physics Faculty of Science UNIVERSITY OF HELSINKI FINLAND An academic dissertation for the the degree of DOCTOR OF PHILOSOPHY to be presented with the permission of the Fac- ulty of Science of University of Helsinki, for public criticism in the lecture hall E204 of Physicum (Gustaf Hällströmin katu 2, Helsinki) on Friday, 19th of October, 2018 at 12 o’clock. HELSINKI 2018 This thesis is typeset in LATEX, using memoir class. HIP internal report series HIP-2018-02 ISBN (paper) 978-951-51-1275-0 ISBN (pdf) 978-951-51-1276-7 ISSN 1455-0563 © Timo Kärkkäinen, 2018 Printed in Finland by Unigrafia. TABLE OF CONTENTS Page 1 Introduction 1 1.1 History ................................... 1 1.1.1 History of non-oscillation neutrino physics . ...... 1 1.1.2 History of neutrino oscillations ................ 3 1.1.3 History of speculative neutrino physics ........... 5 1.2 Standard Model . ........................... 6 1.2.1 Gauge sector . .......................... 8 1.2.2 Kinetic sector . .......................... 9 1.2.3 Brout-Englert-Higgs mechanism ............... 10 1.2.4 Yukawa sector . .......................... 12 1.3 Some problems in the Standard Model ................ 13 1.3.1 Flavour problem ......................... 13 1.3.2 Neutrino masses ......................... 13 1.3.3 Hierarchy problem ........................ 14 1.3.4 Cosmological issues ....................... 14 1.3.5 Strong CP problem ........................ 15 2 Phenomenology of massive light neutrinos 16 2.1 Dirac mass term . ........................... 17 2.2 Weak lepton current .......................... -
JHEP02(2019)129 Ν M Springer October 29, 2018 February 5, 2019 January 29, 2019 February 20, 2019 : : : : 2 Group in LRSM
Published for SISSA by Springer Received: October 29, 2018 Revised: January 29, 2019 Accepted: February 5, 2019 Published: February 20, 2019 Phenomenology of two texture zero neutrino mass in JHEP02(2019)129 left-right symmetric model with Z8 × Z2 Happy Borgohain and Mrinal Kumar Das Department of Physics, Tezpur University, Napaam, Tezpur, Assam-784028, India E-mail: [email protected], [email protected] Abstract: We have done a phenomenological study on the neutrino mass matrix Mν favoring two zero texture in the framework of left-right symmetric model (LRSM) where type I and type II seesaw naturally occurs. The type I SS mass term is considered to be following a trimaximal mixing (TM) pattern. The symmetry realizations of these texture zero structures has been realized using the discrete cyclic abelian Z8 × Z2 group in LRSM. We have studied six of the popular texture zero classes named as A1, A2, B1, B2, B3 and B4 favoured by neutrino oscillation data in our analysis. We basically focused on the implications of these texture zero mass matrices in low energy phenomenon like neutrinoless double beta decay (NDBD) and lepton flavour violation (LFV) in LRSM scenario. For NDBD, we have considered only the dominant new physics contribution coming from the diagrams containing purely RH current and another from the charged Higgs scalar while ignoring the contributions coming from the left-right gauge boson mixing and heavy light neutrino mixing. The mass of the extra gauge bosons and scalars has been considered to be of the order of TeV scale which is accessible at the colliders. -
Foraging Behaviour of the Particle Phenomenologist
Foraging Behaviour of the Particle Phenomenologist A Broad Exploration of Physics Beyond the Standard Model A Dissertation Presented to the Faculty of the Graduate School of Cornell University in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy by Wee Hao Ng December 2018 c 2018 Wee Hao Ng ALL RIGHTS RESERVED Foraging Behaviour of the Particle Phenomenologist A Broad Exploration of Physics Beyond the Standard Model Wee Hao Ng, Ph.D. Cornell University 2018 Despite its numerous successes, the Standard Model (SM) of particle physics is known to be incomplete. In this thesis, we explore a variety of topics regarding physics beyond the SM (BSM). In the minimal supersymmetric Standard Model (MSSM), the leptons and Higgs have separate superpartners; however, it is possible to construct a model where the Higgs is the superpartner of one generation of left-handed leptons. In Chapter 2, we explore various implications of this Higgs-as-slepton model, in par- ticular on electroweak precision and neutrino experiments. In Chapter 3, we use the model to explain various excesses reported in leptoquark and W 0 searches by the CMS experiment in 2014. These excesses were observed in electron but not muon channels, hence suggesting the violation of lepton universality, a hallmark of the model. In Chapter 4, we propose a supersymmetric left-right symmetric (SUSY LRS) model that can explain various excesses reported in W 0 searches by the CMS and ATLAS experiments around 2014–2015, but at the same time generate a large tree-level Higgs mass, hence resolving the usual issue of the Higgs mass being too small in the MSSM. -
Jhep08(2010)115
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Springer - Publisher Connector Published for SISSA by Springer Received: April 27, 2010 Revised: July 22, 2010 Accepted: August 10, 2010 Published: August 25, 2010 An A4 flavor model for quarks and leptons in warped geometry JHEP08(2010)115 Avihay Kadosh and Elisabetta Pallante Centre for Theoretical Physics, University of Groningen, 9747 AG, Netherlands E-mail: [email protected], [email protected] Abstract: We propose a spontaneous A4 flavor symmetry breaking scheme implemented in a warped extra dimensional setup to explain the observed pattern of quark and lepton masses and mixings. The main advantages of this choice are the explanation of fermion mass hierarchies by wave function overlaps, the emergence of tribimaximal neutrino mixing and zero quark mixing at the leading order and the absence of tree-level gauge mediated flavor violations. Quark mixing is induced by the presence of bulk flavons, which allow for \cross-brane" interactions and a \cross-talk" between the quark and neutrino sectors, realizing the spontaneous symmetry breaking pattern A4 ! nothing first proposed in [X.G. He, Y.Y. Keum and R.R. Volkas, JHEP 04 (2006) 039]. We show that the observed quark mixing pattern can be explained in a rather economical way, including the CP violating phase, with leading order cross-interactions, while the observed difference between the smallest CKM entries Vub and Vtd must arise from higher order corrections. Without implementing PLR (or other versions of) custodial symmetry, the bulk mass parameter of the left-handed quarks in this model is constrained by the Zb¯b best fits, still allowing for a Kaluza-Klein scale below 2 TeV. -
Arxiv:Hep-Ph/0601001V4 10 Apr 2006 技文线 中国科技论文在线 Keywords: Symmet the Realising Model Explicit Constructed
中国科技论文在线 http://www.paper.edu.cn Preprint typeset in JHEP style - HYPER VERSION A4 flavour symmetry breaking scheme for understanding quark and neutrino mixing angles Xiao-Gang He NCTS/TPE, Department of Physics, National Taiwan University, Taipei, Taiwan, 10764, Republic of China E-mail: [email protected] Yong-Yeon Keum NCTS/TPE, Department of Physics, National Taiwan University, Taipei, Taiwan, 10764, Republic of China E-mail: [email protected] Raymond R. Volkas School of Physics, Research Centre for High Energy Physics, The University of Melbourne, Victoria 3010, Australia E-mail: [email protected] Abstract: We propose a spontaneous A4 flavour symmetry breaking scheme to under- stand the observed pattern of quark and neutrino mixing. The fermion mass eigenvalues are arbitrary, but the mixing angles are constrained in such a way that the overall pat- terns are explained while also leaving sufficient freedom to fit the detailed features of the observed values, including CP-violating phases. The scheme realises the proposal of Low and Volkas to generate zero quark mixing and tribimaximal neutrino mixing at tree level, arXiv:hep-ph/0601001v4 10 Apr 2006 with deviations from both arising from small corrections after spontaneous A4 breaking. In the neutrino sector, the breaking is A4 Z2, while in the quark and charged-lepton → sectors it is A4 Z3 = C3. The full theory has A4 completely broken, but the two → ∼ different unbroken subgroups in the two sectors force the dominant mixing patterns to be as stated above. Radiative effects within each sector are shown to deviate neutrino mixing from tribimaximal, while maintaining zero quark mixing. -
Trimaximal Neutrino Mixing from Scotogenic $ a 4 $ Family Symmetry
USTC-ICTS/PCFT-20-27 Trimaximal neutrino mixing from scotogenic A4 family symmetry Gui-Jun Ding,1, 2, ∗ Jun-Nan Lu,2, 3, y and Jos´eW. F. Valle3, z 1Peng Huanwu Center for Fundamental Theory, Hefei, Anhui 230026, China 2Interdisciplinary Center for Theoretical Study and Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026, China 3AHEP Group, Institut de F´ısica Corpuscular { C.S.I.C./Universitat de Val`encia,Parc Cient´ıficde Paterna. C/ Catedr´atico Jos´eBeltr´an,2 E-46980 Paterna (Valencia) - SPAIN We propose a flavour theory of leptons implementing an A4 family symmetry. Our scheme provides a simple way to derive trimaximal neutrino mixing from first principles, leading to simple and testable predictions for neutrino mixing and CP violation. Dark matter mediates neutrino mass generation, as in the simplest scotogenic model. I. INTRODUCTION The discovery of neutrino oscillations [1{3] constitutes a milestone in particle physics, yet we are still far from understanding the pattern of lepton mixing parameters. Indeed, the flavor problem of particle physics has, in the lepton sector, its most challenging expression. Likewise, the basic understanding and interpretaion of cosmological dark matter remains a challenge [4]. Many educated guesses have been proposed as to what the pattern of lepton mixing should look like. Such phenomenological patterns of neutrino mixing include, for example, Tri-bimaximal (TBM) [5, 6], Trimaximal (TM1/TM2) [7{9] and bi-large mixing patterns [10{13]. Some of these have been generalized [14], especially after [15, 16] the non-zero value of the mixing angle θ13 was established by reactor experiments Daya Bay [17] and RENO [18].