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The anomalous dimension matrix of dimensionally regularized four-quark operators is known to be affected by evanescent operators, which vanish in $D=4$ dimensions. Their definition, however, is not unique, as one can always redefine them by…

High Energy Physics - Phenomenology · Physics 2015-06-25 Stefan Herrlich , Ulrich Nierste

The fermions of the Standard Model are integrated out to obtain the effective Lagrangian in the sector violating P and CP at zero temperature. We confirm that no contributions arise for operators of dimension six or less and show that the…

High Energy Physics - Phenomenology · Physics 2011-06-03 L. L. Salcedo

Four independent dimension-eight operators give rise to anomalous neutral triple gauge boson interactions, one CP-even and three CP-odd. Only the CP-even operator interferes with the Standard Model for the production of a pair of on-shell…

High Energy Physics - Phenomenology · Physics 2016-08-16 Celine Degrande

This article presents a full operator analytical method for studying the quadratic nonlinear interactions in quantum optomechanics. The method is based on the application of higher-order operators, using a six-dimensional basis of second…

Quantum Physics · Physics 2018-11-13 Sina Khorasani

The most general basis of operators parametrizing a low-scale departure from the SM particle content is constructed. The SM gauge invariance is enforced, and operators of lowest dimensions are retained separately for a new light neutral…

High Energy Physics - Phenomenology · Physics 2015-06-03 Jernej F. Kamenik , Christopher Smith

We study diagonal and transition quark dipole operators in a class of extended technicolor (ETC) models, taking account of the multiscale nature of the ETC gauge symmetry breaking and of the mixing among ETC interaction eigenstates. Because…

High Energy Physics - Phenomenology · Physics 2009-11-10 Thomas Appelquist , Maurizio Piai , Robert Shrock

We calculate the two-loop QCD anomalous dimension matrix (ADM) gamma^(1)_NDR in the NDR-MSbar scheme for all the flavour-changing four-quark dimension-six operators that are relevant in both the Standard Model and its extensions. Both…

High Energy Physics - Phenomenology · Physics 2024-02-15 Andrzej J. Buras , Mikolaj Misiak , Joerg Urban

We extend the standard top-quark Yukawa coupling with a dimension-6 operator in order to accommodate a CP violating complex phase with manifest gauge invariance. This leads to a new $ttHH$ contact interaction, along with many Goldstone…

High Energy Physics - Phenomenology · Physics 2024-12-31 Ya-Juan Zheng

New physics interactions can affect the strength and structure of the $tbW$ vertex. We investigate the magnitudes and phases of "anomalous" contributions to this vertex in a two-Higgs doublet and the minimal supersymmetric extension of the…

High Energy Physics - Phenomenology · Physics 2009-03-24 Werner Bernreuther , Patrick Gonzalez , Martin Wiebusch

The origin and the implications of higher dimensional effective operators in 4-dimensional theories are discussed in non-supersymmetric and supersymmetric cases. Particular attention is paid to the role of general, derivative-dependent…

High Energy Physics - Phenomenology · Physics 2010-04-21 I. Antoniadis , E. Dudas , D. M. Ghilencea , P. Tziveloglou

We analyze the impact of QCD corrections on limits derived from neutrinoless double beta decay ($0\nu\beta\beta$). As demonstrated previously, the effect of the color-mismatch arising from loops with gluons linking the quarks from different…

High Energy Physics - Phenomenology · Physics 2017-07-19 Carolina Arbeláez , Marcela González , Sergey Kovalenko , Martin Hirsch

We derive bounds on Higgs and gauge--boson anomalous interactions using the CDF data for the process $p \bar{p} \to \gamma\gamma\gamma + X$. We use a linearly realized $SU_L(2) \times U_Y(1)$ invariant effective Lagrangian to describe the…

High Energy Physics - Phenomenology · Physics 2009-10-31 F. de Campos , M. C. Gonzalez-Garcia , S. M. Lietti , S. F. Novaes , R. Rosenfeld

We calculate expectation values of QCD operators consisting of the products of the four operators of the light quarks corresponding to the scalar, pseudoscalar, vector, pseudovector (axial) and tensor Lorentz structures in the nucleon. All…

High Energy Physics - Phenomenology · Physics 2009-11-10 E. G. Drukarev , M. G. Ryskin , V. A. Sadovnikova , V. E. Lyubovitskij , Th. Gutsche , Amand Faessler

We probe the dimension-six operators contributing to Higgs production in association with a $Z$ boson at the future high-luminosity electron-positron colliders. Potential constraints on dimension-six operators in the Higgs sector are…

High Energy Physics - Phenomenology · Physics 2017-03-29 Hamzeh Khanpour , Mojtaba Mohammadi Najafabadi

We revisit the extraction of the triple electroweak gauge boson couplings from the Large Hadron Collider Run I data on the $W^+W^-$ and $W^\pm Z$ productions when the analysis also contains additional operators that modify the couplings of…

High Energy Physics - Phenomenology · Physics 2018-07-25 Alexandre Alves , N. Rosa-Agostinho , Oscar J. P. Éboli , M. C. Gonzalez--Garcia

Recent LHCb results on the decay $B \to K^\ast \mu^+ \mu^-$ show significant deviations from the SM estimates in some of the angular correlations. In this paper we study the possibility of explaining these deviations using new scalar…

High Energy Physics - Phenomenology · Physics 2014-04-23 Alakabha Datta , Murugeswaran Duraisamy , Diptimoy Ghosh

The anomalous dimensions of trilinear-quark operators are calculated at leading twist $t=3$ by diagonalizing the one-gluon exchange kernel of the renormalization-group type evolution equation for the nucleon distribution amplitude. This is…

High Energy Physics - Phenomenology · Physics 2009-10-31 M. Bergmann , W. Schroers , N. G. Stefanis

A general discussion is presented of the single logarithmic soft factor that appears in two scale QCD observables in processes involving four partons. We treat it as the ``fifth form factor'', accompanying the four collinear singular…

High Energy Physics - Phenomenology · Physics 2009-11-11 Yu. L. Dokshitzer , G. Marchesini

Leptoquarks (LQs) have attracted increasing attention within recent years, mainly since they can explain the flavor anomalies found in $R(D^{(*)})$, $b \rightarrow s \ell^+ \ell^-$ transitions and the anomalous magnetic moment of the muon.…

High Energy Physics - Phenomenology · Physics 2022-06-22 Andreas Crivellin , Luc Schnell

The search for neutrinoless double beta decay of nuclei is believed to be one of the most promising means to search for new physics. Observation of this very rare nuclear process, which violates Lepton Number conservation, would imply the…