{"title":"Interplay of type-I and type-II seesaw in neutrinoless double beta decay in left-right symmetric model","authors":"","doi":"10.1016/j.nuclphysb.2024.116623","DOIUrl":null,"url":null,"abstract":"<div><p>The left-right symmetric models (LRSM) generally include type-I and type-II induced seesaw masses as a hybrid mass for the light-active neutrinos. Assuming a particular form of Dirac-type coupling, the Majorana-type coupling present in the seesaw mass formula can be expressed in terms of low-energy neutrino oscillation observables and vacuum expectation values (vevs) of the scalar fields present in the model. The Majorana-type coupling thus admits eight different solutions by considering whether the type-I and type-II terms dominate the light neutrino mass. We study the role of all eight solutions in the lepton number violating neutrinoless double beta decay (<span><math><mn>0</mn><mi>ν</mi><mi>β</mi><mi>β</mi></math></span>) process. In LRSM, the right-handed neutrinos, triplet scalars, and gauge bosons of the left and right sectors act as mediators of new contributions to the <span><math><mn>0</mn><mi>ν</mi><mi>β</mi><mi>β</mi></math></span> process. As a result, the effective mass of electron neutrino appearing in the decay width would be a function of <span><math><msub><mrow><mi>v</mi></mrow><mrow><mi>R</mi></mrow></msub></math></span> (vev of the Higgs triplet of the right sector) along with other parameters of the model, through the masses of the new contributions. The energy scale, <span><math><msub><mrow><mi>v</mi></mrow><mrow><mi>R</mi></mrow></msub></math></span> can be considered as the new physics scale which allows exploring physics beyond the Standard Model. Considering the present and future sensitivity of searches of <span><math><mn>0</mn><mi>ν</mi><mi>β</mi><mi>β</mi></math></span>, we study the role of eight different solutions of the Majorana coupling matrix. In our study, the inverted hierarchy of light neutrino masses is disfavored for all solutions keeping future sensitivity of effective mass in the picture, if the lightest mass of active neutrinos is below 0.001 eV. Also, our study shows a possibility of new physics contributions saturating the experimental bound on effective mass for <span><math><msub><mrow><mi>v</mi></mrow><mrow><mi>R</mi></mrow></msub></math></span> in the range of 10 TeV for two particular solutions of the Majorana coupling matrix and simultaneously provides the insights about parity breaking scale.</p></div>","PeriodicalId":54712,"journal":{"name":"Nuclear Physics B","volume":null,"pages":null},"PeriodicalIF":2.5000,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0550321324001895/pdfft?md5=fa628352c9f31036801eeaf1d1b6dd5c&pid=1-s2.0-S0550321324001895-main.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Nuclear Physics B","FirstCategoryId":"101","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0550321324001895","RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"PHYSICS, PARTICLES & FIELDS","Score":null,"Total":0}
引用次数: 0
Abstract
The left-right symmetric models (LRSM) generally include type-I and type-II induced seesaw masses as a hybrid mass for the light-active neutrinos. Assuming a particular form of Dirac-type coupling, the Majorana-type coupling present in the seesaw mass formula can be expressed in terms of low-energy neutrino oscillation observables and vacuum expectation values (vevs) of the scalar fields present in the model. The Majorana-type coupling thus admits eight different solutions by considering whether the type-I and type-II terms dominate the light neutrino mass. We study the role of all eight solutions in the lepton number violating neutrinoless double beta decay () process. In LRSM, the right-handed neutrinos, triplet scalars, and gauge bosons of the left and right sectors act as mediators of new contributions to the process. As a result, the effective mass of electron neutrino appearing in the decay width would be a function of (vev of the Higgs triplet of the right sector) along with other parameters of the model, through the masses of the new contributions. The energy scale, can be considered as the new physics scale which allows exploring physics beyond the Standard Model. Considering the present and future sensitivity of searches of , we study the role of eight different solutions of the Majorana coupling matrix. In our study, the inverted hierarchy of light neutrino masses is disfavored for all solutions keeping future sensitivity of effective mass in the picture, if the lightest mass of active neutrinos is below 0.001 eV. Also, our study shows a possibility of new physics contributions saturating the experimental bound on effective mass for in the range of 10 TeV for two particular solutions of the Majorana coupling matrix and simultaneously provides the insights about parity breaking scale.
期刊介绍:
Nuclear Physics B focuses on the domain of high energy physics, quantum field theory, statistical systems, and mathematical physics, and includes four main sections: high energy physics - phenomenology, high energy physics - theory, high energy physics - experiment, and quantum field theory, statistical systems, and mathematical physics. The emphasis is on original research papers (Frontiers Articles or Full Length Articles), but Review Articles are also welcome.