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Related papers: Pionic Matrix Elements in Neutrinoless Double-Beta…

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We extend the Zee model by introducing a vector-like lepton doublet and a flavor dependent global $U(1)$ symmetry. Flavor changing neutral currents in the quark sector can be naturally forbidden at tree level due to the $U(1)$ symmetry,…

High Energy Physics - Phenomenology · Physics 2021-09-15 Toshinori Matsui , Takaaki Nomura , Kei Yagyu

It is shown that the K -> pi pi matrix elements of the four-quark operator Q_7, generated by the electroweak penguin-like diagrams of the Standard Model, can be calculated to first non-trivial order in the chiral expansion and in the 1/Nc…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Knecht , S. Peris , E. de Rafael

Within the collective coordinate approach to chiral soliton models we suggest that breaking of SU(3) flavor symmetry mainly resides in the baryon wave-functions while the charge operators have no (or only small) symmetry breaking…

High Energy Physics - Phenomenology · Physics 2007-05-23 H. Weigel

We compute the leading-logarithmic correction to the neutrino mass matrix in the Standard Model effective field theory (SMEFT) to dimension seven. In the limit of negligible lepton and down-type quark Yukawa couplings, it receives…

High Energy Physics - Phenomenology · Physics 2021-08-06 Mikael Chala , Arsenii Titov

Models involving large extra spatial dimension(s) have interesting predictions on lepton flavor violating processes. We consider some 5D models which are related to neutrino mass generation or address the fermion masses hierarchy problem.…

High Energy Physics - Phenomenology · Physics 2011-07-19 We-Fu Chang , John N. Ng

We study charged lepton flavour violation in a scenario in which light neutrino masses are generated via the inverse seesaw mechanism with 3+3 gauge singlet fermions, Ni and Sj, i,j=1,2,3. Lepton mixing is predicted with the help of the…

High Energy Physics - Phenomenology · Physics 2025-07-18 F. P. Di Meglio , C. Hagedorn

We derive predictions for the Dirac phase $\delta$ present in the $3\times 3$ unitary neutrino mixing matrix $U = U_e^{\dagger} \, U_{\nu}$, where $U_e$ and $U_{\nu}$ are $3\times 3$ unitary matrices which arise from the diagonalisation,…

High Energy Physics - Phenomenology · Physics 2015-11-10 I. Girardi , S. T. Petcov , A. V. Titov

Dark particles with lepton-flavor-violating couplings to the tau lepton can induce rare neutrinoless $\tau$ decays with large final state multiplicities. We study models where transitions of the type $\tau^\pm\to \ell^\pm\,\phi$, with…

High Energy Physics - Phenomenology · Physics 2026-04-03 Yohei Ema , Patrick J. Fox , Matheus Hostert , Tony Menzo , Maxim Pospelov , Anupam Ray , Jure Zupan

In this paper, we investigate three symmetry breaking effects in strong and radiative decays of strange heavy mesons. We study 1/m_Q corrections within the heavy quark effect theory, as well as SU(3) and SU(2) symmetry breakings induced by…

High Energy Physics - Phenomenology · Physics 2016-02-17 Chi-Yee Cheung , Chien-Wen Hwang

Fermion masses and mixing angles including that of neutrinos are studied in a model with symmetry group SUSY $SO(10)\times \Delta (48) \times U(1)$. Universality of Yukawa coupling of superfields is assumed. The resulting texture of mass…

High Energy Physics - Phenomenology · Physics 2007-05-23 K. C. Chou , Y. L. Wu

We investigate two-neutrino double beta decay ($2\nu\beta\beta$) in chiral effective field theory. We find contributions from weak magnetism and double-weak pion-exchange at next-to-leading-order in the chiral power counting. We discuss the…

High Energy Physics - Phenomenology · Physics 2024-12-19 Saad el Morabit , Ryan Bouabid , Vincenzo Cirigliano , Jordy de Vries , Lukáš Gráf , Emanuele Mereghetti

We present a novel mode of neutrinoless double beta decay with emission of a light Majoron-like scalar particle phi. We assume it couples via an effective seven-dimensional operator with a (V+A) lepton current and (V+-A) quark currents…

High Energy Physics - Phenomenology · Physics 2019-05-16 Ricardo Cepedello , Frank F. Deppisch , Lorena González , Chandan Hati , Martin Hirsch

We study supersymmetric extra U(1) model with $S_4$ flavor symmetry. The flavor symmetry not only stabilizes proton but also suppresses the flavor changing processes without raising the supersymmetry breaking scale. After the flavor…

High Energy Physics - Phenomenology · Physics 2020-12-01 Yasuhiro Daikoku , Hiroshi Okada

We discuss lepton number violating processes in the context of long-baseline neutrino oscillations. We summarise and compare neutrino flavour oscillations in quantum mechanics and quantum field theory, both for standard oscillations and for…

High Energy Physics - Phenomenology · Physics 2019-06-19 Patrick D. Bolton , Frank F. Deppisch

We consider an $SU(3)_L\otimes U(1)_N$ model for the electroweak interactions which includes extra charged leptons which do not mix with the known leptons. These new leptons couple to $Z^0$ only through vector currents. We consider…

High Energy Physics - Phenomenology · Physics 2009-10-22 V. Pleitez , M. D. Tonasse

$K \to \pi$ and $K \to 0$ weak matrix elements of $\Delta S = 1$ operators have been measured in 2+1 flavor domain wall fermion (DWF) QCD on (3 fm)$^3$ lattices with $a^{-1} = 1.73(3)$ GeV. As is well known, using these matrix elements and…

High Energy Physics - Lattice · Physics 2009-04-14 Shu Li , Robert D. Mawhinney for RBC , UKQCD Collaborations

We study the lepton flavor violation in the supersymmetric seesaw model taking into account recent experimental improvements, especially for the Higgs boson mass measurement, direct searches of superpartners and the rare decay of B_s -> mu+…

High Energy Physics - Phenomenology · Physics 2015-03-05 Toru Goto , Yasuhiro Okada , Tetsuo Shindou , Minoru Tanaka , Ryoutaro Watanabe

While the detection of $W_R$-boson at the Large Hadron Collider is likely to resolve the mystery of parity violation in weak interaction, observation of neutrinoless double beta decay ($0\nu\beta\beta$) is expected to determine whether…

High Energy Physics - Phenomenology · Physics 2013-09-03 Ram Lal Awasthi , M. K. Parida , Sudhanwa Patra

We propose a model based on the gauge group $SU(3)_{C}\otimes SU(3)_{L}\otimes U(1)_{X}$ with an extra $S_{3}$ flavor symmetry, which accounts for the lepton masses and mixing. The small active neutrino masses are generated via a double…

High Energy Physics - Phenomenology · Physics 2014-10-15 A. E. Cárcamo Hernández , E. Cataño Mur , R. Martinez

Present precision measurements of the neutron life time lead to a CKM matrix element $|V_{ud}|$ which is three standard deviations off the value inferred from heavy quark decays etc. We investigate the possibility whether isospin-breaking…

Nuclear Theory · Physics 2009-11-07 N. Kaiser