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Related papers: Parity Doubling and the S Parameter Below the Conf…

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We study the SU(2) gauge theory on the lattice with different numbers of fermions in the fundamental representation of the gauge group to explore the gauge theory phase diagram. We find evidence for an infrared fixed point for ten flavors.…

High Energy Physics - Lattice · Physics 2012-01-11 Tuomas Karavirta , Jarno Rantaharju , Kari Rummukainen , Kimmo Tuominen

We present new results for the SU(3) "sextet model" with two flavors transforming according to the two-index symmetric representation of the gauge group. The simulations are performed using unimproved Wilson fermions. We measure the meson…

High Energy Physics - Lattice · Physics 2016-07-26 Vincent Drach , Martin Hansen , Ari Hietanen , Claudio Pica , Francesco Sannino

We stress the importance of the circa 20 parameters in the Standard Model, which are not fixed by the model but only determined experimentally, as a window to the physics beyond the Standard Model. However, it is a tiny window in as far as…

High Energy Physics - Phenomenology · Physics 2015-06-25 C. D. Froggatt , H. B. Nielsen

We study the dynamics of SU(2) gauge theory with NF=6 Dirac fermions by means of lattice simulation to investigate if they are appropriate to realization of electroweak symmetry breaking. The discrete analogue of beta function for the…

High Energy Physics - Lattice · Physics 2012-10-19 M. Hayakawa , K. -I. Ishikawa , Y. Osaki , S. Takeda , N. Yamada

We study the chiral condensate $<\bar{\psi} \psi>$ for an SU(3) gauge theory with $N_f$ massless Dirac fermions in the fundamental representation when $N_f$ is increased from 2 to 6. For $N_f=2$, our lattice simulations of $<\bar{\psi} \psi…

We study the evolution of the coupling in SU(2) gauge field theory with $N_f=4$, 6 and 10 fundamental fermion flavours on the lattice. These values are chosen close to the expected edges of the conformal window, where the theory possesses…

High Energy Physics - Lattice · Physics 2015-03-19 Tuomas Karavirta , Jarno Rantaharju , Kari Rummukainen , Kimmo Tuominen

We compute the electroweak S and T parameters induced by SU(2)_L triplet scalars up to one-loop order. We consider the most general renormalizable potential for a triplet and the Standard Model Higgs doublet. Our calculation is performed by…

High Energy Physics - Phenomenology · Physics 2013-05-30 Zuhair U. Khandker , Daliang Li , Witold Skiba

We discuss a mechanism which can reduce the S and T parameters in dynamical electroweak symmetry breaking scenario. It is interesting that not only T but also S parameters can be made small even if large isospin violation exists, which can…

High Energy Physics - Phenomenology · Physics 2011-04-15 Nobuhiro Maekawa

Two particular ratios related to mesons are proposed for the study of the conformal window in $SU(3)$ gauge theory and fundamental fermions. Lattice and other studies indicate that the lower end, $N_f^*$, is at around 7 - 13 flavors which…

High Energy Physics - Lattice · Physics 2023-11-16 Hee Sok Chung , Daniel Nogradi

A novel strong interaction beyond the standard model could provide a dynamical explanation of electroweak symmetry breaking. Experimental results strongly constrain properties of models that realise this mechanism. Whether these constraints…

High Energy Physics - Lattice · Physics 2015-09-02 Biagio Lucini

We summarize basic features associated to dynamical breaking of the electroweak symmetry. The knowledge of the phase diagram of strongly coupled theories as function of the number of colors, flavors and matter representation plays a…

High Energy Physics - Phenomenology · Physics 2012-11-27 Francesco Sannino

Dilaton effective field theory (dEFT) can be employed to analyze lattice data in gauge theories that lie in close proximity of the lower edge of the conformal window. Under special conditions, we show that it can be used as a diagnostic…

High Energy Physics - Lattice · Physics 2026-02-09 Thomas Appelquist , James Ingoldby , Maurizio Piai

The knowledge of the phase diagram of strongly coupled theories as function of the number of colors, flavors and matter representation plays a fundamental role when constructing viable extensions of the standard model (SM) featuring…

High Energy Physics - Phenomenology · Physics 2008-06-25 Francesco Sannino

We study the SU(3) gauge theory with twelve flavours of fermions in the fundamental representation as a prototype of non-Abelian gauge theories inside the conformal window. Guided by the pattern of underlying symmetries, chiral and…

High Energy Physics - Lattice · Physics 2015-06-23 M. P. Lombardo , K. Miura , T. J. Nunes da Silva , E. Pallante

We discuss the existence of a conformal phase in SU(N) gauge theories in four dimensions. In this lattice study we explore the model in the bare parameter space, varying the lattice coupling and bare mass. Simulations are carried out with…

High Energy Physics - Phenomenology · Physics 2010-10-26 A. Deuzeman , M. P. Lombardo , E. Pallante

We explore aspects of the phase structure of SU(2) and SU(3) lattice gauge theories at strong coupling with many flavours $N_f$ of Wilson fermions in the fundamental representation. The pseudoscalar meson mass as a function of hopping…

High Energy Physics - Lattice · Physics 2010-04-30 Kei-ichi Nagai , Georgina Carrillo-Ruiz , Gergana Koleva , Randy Lewis

In this work, we study a scotogenic extension of the Standard Model featuring two inert scalar doublets and three singlet Majorana fermions, where neutrino masses are generated radiatively at one loop. The lightest among the Majorana…

High Energy Physics - Phenomenology · Physics 2026-03-31 Abdelrahman AbuSiam , Amine Ahriche

We have performed an overall fit to the electroweak data with the generation blind $U(1)$ extension of the Standard Model. As input data for fitting we have included the asymmetry parameters, the particle decay widths of $Z$, neutrino…

High Energy Physics - Phenomenology · Physics 2011-01-25 K. Agashe , M. Graesser , Ian Hinchliffe , M. Suzuki

In the exploration of viable models of dynamical electroweak symmetry breaking, it is essential to locate the lower end of the conformal window and know the mass anomalous dimensions there for a variety of gauge theories. We calculate, with…

High Energy Physics - Lattice · Physics 2013-11-27 M. Hayakawa , K. -I. Ishikawa , S. Takeda , N. Yamada

From the global chiral SU(2)*U(1) that appears in the electroweak Left-Right Model in the fundamental representation, a continuous transition to the representation of the minimal Standard Model is considered in the Cartan subalgebra of the…

High Energy Physics - Theory · Physics 2007-05-23 R. Bonisch