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

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In order to explain the fermion masses and mixings naturally, we introduce a specific flavor symmetry and mass suppression pattern that constrain the flavor structure of the fermion Yukawa couplings. Our model describes why the hierarchy of…

High Energy Physics - Phenomenology · Physics 2015-06-18 Y. H. Ahn , Paolo Gondolo

This paper present a systematic study of hyperon non-leptonic two-body decays induced by light quark transitions, particularly the $s \rightarrow u\bar{u}d$ process, within the framework of SU(3) flavor symmetry. The effective weak…

High Energy Physics - Phenomenology · Physics 2025-05-27 Xin Wu , Qi Chen , Ye Xing , Zhi-Peng Xing , Ruilin Zhu

We consider the effect of Planck scale operators on neutrino mixing. We assume that GUT scale operators give rise to degenerate neutrino masses with bimaximal mixing. Quantum gravity (Planck scale) effects lead to an effective SU(2)L*U(1)…

High Energy Physics - Phenomenology · Physics 2008-11-26 Bipin Singh Koranga , Mohan Narayan , S. Uma Sankar

The observed pattern of neutrino mixing may be the result of a 2-3($ \mu- \tau$) symmetry in the leptonic sector. We consider a two Higgs doublet model with a 2-3 symmetry in the down type quark and the charged lepton sector. The breaking…

High Energy Physics - Phenomenology · Physics 2009-11-11 Alakabha Datta , Patrick J. O'Donnell

We propose a new model with the Majorana neutrino masses generated at two-loop level, in which the lepton number violation (LNV) processes, such as neutrinoless double beta decays, are mainly induced by the dimension-7 LNV effective…

High Energy Physics - Phenomenology · Physics 2015-07-14 Chao-Qiang Geng , Da Huang , Lu-Hsing Tsai , Qing Wang

We propose a scheme, based on \Delta(27) flavor symmetry and supplemented by other discrete symmetries and inverse seesaw mechanism, where both the light neutrino masses and the deviation from tri-bimaximal mixing matrix can be linked to…

High Energy Physics - Phenomenology · Physics 2016-01-27 M. Abbas , S. Khalil , A. Rashed , A. Sil

In this work we introduce CPT-odd non-minimal Lorentz-symmetry violating couplings to the electroweak sector modifying the interaction between leptons and gauge bosons. The vertex rules allow us to calculate tree-level processes modified by…

High Energy Physics - Phenomenology · Physics 2020-04-08 Y. M. P. Gomes , P. C. Malta , M. J. Neves

We propose a new model for describing baryon semi-leptonic decays for estimating $F$ and $D$ values with explicit breaking effects of both SU(3) and SU(2) flavor symmetry, where all possible SU(3) and SU(2) breaking effects are induced from…

High Energy Physics - Phenomenology · Physics 2008-11-26 T. Yamanishi

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 maintain a symmetric structure. Sizable symmetry…

High Energy Physics - Phenomenology · Physics 2009-10-31 H. Weigel

We phenomenologically build a neutrino mass matrix obeying $\mu-\tau$ symmetry with only two parameters, Cabibbo angle $(\lambda)$ and a flavour twister parameter $(\eta)$. For vanishing $\eta$, the model assumes TBM mixing. When…

High Energy Physics - Phenomenology · Physics 2013-04-09 Subhankar Roy , N. Nimai Singh

Global analysis of neutrino oscillation data slightly favors normal mass ordering. In this work, we investigate an extended scalar sector that naturally gives rise to a type I + II seesaw mechanism after spontaneous symmetry breaking and…

High Energy Physics - Phenomenology · Physics 2025-10-22 Maria Aguilar , Juan Carlos Helo , Toshihiko Ota , Farinaldo S. Queiroz , David Suarez , Amanda Rodríguez

We present the first direct evaluation of DI = 3/2 K -> pi pi matrix elements with the aim of determining all the low-energy constants at NLO in the chiral expansion. Our numerical investigation demonstrates that it is indeed possible to…

High Energy Physics - Lattice · Physics 2008-11-26 P. Boucaud , V. Gimenez , C-J. D. Lin , V. Lubicz , G. Martinelli , M. Papinutto , C. T. Sachrajda

The minimal Standard Model exhibits a nontrivial chiral U(2) symmetry if the vev and the hypercharge splitting (Delta) of right-handed leptons (quarks) in a family vanish and Q=T_0 + Y independently in each helicity sector. As a…

High Energy Physics - Theory · Physics 2009-10-28 R. Bonisch

Hadronic tau decay data provides access to the light quark vector (V) and axial vector (A) spectral functions. This makes possible investigations of the dynamics of QCD at intermediate scales and improved determinations of certain…

High Energy Physics - Phenomenology · Physics 2009-11-07 Kim Maltman

Supersymmetric contributions to all leptonic electromagnetic dipole operators have essentially identical diagramatic structure. With approximate slepton universality this allows the muon anomalous magnetic moment to be related to the…

High Energy Physics - Phenomenology · Physics 2009-11-07 Michael Graesser , Scott Thomas

We present results for Delta I=3/2 and Delta S=2 matrix elements relevant for CP violation in K->Pi Pi decays and for the K_S-K_L mass difference in the standard model and beyond. They were obtained with Neuberger fermions on quenched gauge…

We discuss a preliminary study of the impact of duality violations on extractions from tau decay data of the D=6 VEVs which determine chiral limit Standard Model K-->pi pi matrix elements of the electroweak penguin operators.

High Energy Physics - Phenomenology · Physics 2015-05-30 D. Boito , O. Cata , M. Golterman , M. Jamin , K. Maltman , J. Osborne , S. Peris

The possible Majorana nature of neutrinos leads to lepton-number-violating effects such as neutrinoless double beta decay. The standard study of this process involves mass-dependent matrix elements which, although easy to use, might be…

High Energy Physics - Phenomenology · Physics 2025-05-26 Vaisakh Plakkot

The leptonic sector in a recently proposed minimal extension of the standard model, in which the permutation symmetry S_3 is assumed to be an exact flavor symmetry at the weak scale, is revisited. We find that S_3 with an additional Z_{N}…

High Energy Physics - Phenomenology · Physics 2015-06-25 Jisuke Kubo

There is no guarantee that the violation of lepton number, assuming it exists, will primarily manifest itself in neutrinoless double beta decay ($0\nu\beta\beta$). Lepton-number violation and lepton-flavor violation may be related, and…

High Energy Physics - Phenomenology · Physics 2017-06-14 Jeffrey M. Berryman , André de Gouvêa , Kevin J. Kelly , Andrew Kobach