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Related papers: $b\to s \gamma$ in Littlest Higgs Model

200 papers

Rare $b$ decay processes are analyzed in the multi-Higgs doublet model. Taking account of the constraint from the $b\to s \gamma$ process, the branching ratio and the forward-backward asymmetry of the final leptons for the $b\to s \ell^+…

High Energy Physics - Phenomenology · Physics 2009-10-30 Yasuhiro Okada , Yasuhiro Shimizu , Minoru Tanaka

We consider the radiative decay b \to s \gamma in a supersymmetric extension of the standard model of particle interactions, where the $b$-quark mass is entirely radiative in origin. This is accomplished by the presence of nonholomorphic…

High Energy Physics - Phenomenology · Physics 2009-10-31 Ernest Ma , Martti Raidal

We study models that interpolate between an elementary and a composite Higgs boson. Such models, arising in theories with new vector-like fermions with electro-weak quantum numbers and charged under a confining gauge interaction, are…

High Energy Physics - Phenomenology · Physics 2018-08-29 Daniele Barducci , Stefania De Curtis , Michele Redi , Andrea Tesi

Using the Higgs boson mass $m_h=125$ GeV, the radiative Higgs decays $h\rightarrow\gamma \nu_l\bar\nu_l$ with $\nu_l = \nu_e,\,\nu_\mu$ and $\nu_\tau$ are analyzed in the standard model. Our calculation shows that the inclusive width of…

High Energy Physics - Phenomenology · Physics 2014-02-05 Yi Sun , Dao-Neng Gao

We analyze the loop induced decays of the Higgs boson into pairs of gluons and photons in the Littlest Higgs model. We find that the deviation of the partial widths for these decays relative to their Standard Model values scales with 1/f^2,…

High Energy Physics - Phenomenology · Physics 2010-04-05 Tao Han , Heather E. Logan , Bob McElrath , Lian-Tao Wang

The variety of ideas put forward in the context of a "composite" picture for the Higgs boson calls for a simple and effective description of the related phenomenology. Such a description is given here by means of a "minimal" model and is…

High Energy Physics - Phenomenology · Physics 2008-11-26 Riccardo Barbieri , Brando Bellazzini , Vyacheslav S. Rychkov , Alvise Varagnolo

In the framework of the littlest Higgs model with T-parity (LHT), we study the contributions of the T-even and T-odd particles to the branching ratio R_b. We find that the precision data of R_b can give strong constraints on the masses of…

High Energy Physics - Phenomenology · Physics 2009-11-06 Xiao-Fang Han

QCD corrections to $b \to s \gamma$ decay in the two Higgs doublet model are calculated from the energy scale of top quark to that of bottom. The constraints on the two Higgs doublet model from the new experimental bounds of $b\to s\gamma$…

High Energy Physics - Phenomenology · Physics 2007-05-23 Cai-Dian Lu

Most of the analysis of composite Higgs have focussed on the Minimal Composite Higgs Model, based on the coset SO(5)$\times$U(1)$_X$/SO(4)$\times$U(1)$_X$. We consider a model based on the coset of simple groups SO(7)/SO(6), with…

High Energy Physics - Phenomenology · Physics 2020-01-29 Leandro Da Rold , Alejo N. Rossia

We study the penguin induced transition $b\to s\ \gamma$ in the minimal N=1 supersymmetric extension of the Standard Model with radiative breaking of the electroweak group. We include the effects of one-loop corrections to the Higgs…

High Energy Physics - Phenomenology · Physics 2009-10-28 Stefano Bertolini , Francesco Vissani

We analyse the constraints on dimension-six Delta F=1 effective operators in models respecting the MFV hypothesis, both in the one-Higgs doublet case and in the two-Higgs doublet scenario with large tan beta. The constraints are derived…

High Energy Physics - Phenomenology · Physics 2008-12-18 Tobias Hurth , Gino Isidori , Jernej F. Kamenik , Federico Mescia

Little Higgs Models are promising constructs to solve the hierarchy problem affecting the Higgs boson mass for generic new physics. However, their preservation of lepton universality forbids them to account for the $H\to\tau\mu$ CMS hint…

High Energy Physics - Phenomenology · Physics 2016-09-08 Andrea Lami , Pablo Roig

With the Higgs search program already quite mature, there is the exciting possibility of discovering a new particle with rates near that of the SM Higgs. We consider models with a signal in $\gamma \gamma$ below the SM Higgs mass, taking…

High Energy Physics - Phenomenology · Physics 2018-08-29 Patrick J. Fox , Neal Weiner

We show that the present limit on the inclusive decay $b\rightarrow s\gamma$ provides strong constraints on Technicolor models. In particular, small values of $F_\pi$ and the mass of charged octet and singlet technipions are excluded,…

High Energy Physics - Phenomenology · Physics 2009-10-28 Bhashyam Balaji

We discuss the connections between the recently observed Higgs-like particle and rare B decays in the context of two Higgs doublet models (2HDMs). The measured decays of the Higgs boson to fermions and gauge bosons, along with the…

High Energy Physics - Phenomenology · Physics 2013-03-27 Chien-Yi Chen , S. Dawson

Recent re-evaluations of the Standard Model (SM) contribution to ${\mathcal Br(b\to s\gamma)$ hint at a positive correction from new physics. Since a charged Higgs boson exchange always gives a positive contribution to this branching ratio,…

High Energy Physics - Phenomenology · Physics 2010-04-14 Ning Chen , Daniel Feldman , Zuowei Liu , Pran Nath

New limits on the Higgs mass from LEP and new calculations on the radiative (penguin) decay of the b->s gamma branching ratio restrict the parameter space of the Constrained Minimal Supersymmetric Standard Model (CMSSM). We find that for…

High Energy Physics - Phenomenology · Physics 2009-10-31 W. de Boer , H. J. Grimm , A. V. Gladyshev , D. I. Kazakov

At $\sqrt{s} = 7$ TeV, the standard model needs at least $10\, (fb)^{-1}$ integrated luminosity at LHC to make a definitive discovery of the Higgs boson. Using binary tetrahedral ($T^{'}$) discrete flavor symmetry, we discuss how the decay…

High Energy Physics - Phenomenology · Physics 2010-12-24 Paul H. Frampton , Chiu Man Ho , Thomas W. Kephart , Shinya Matsuzaki

The observation that the $b \rightarrow s\gamma $ decay rate is close to the Standard Model value implies a large mass for the charged-Higgs boson in the Minimum Supersymmetric Standard Model, that nearly closes the $t \rightarrow b H^+$…

High Energy Physics - Phenomenology · Physics 2009-09-15 V. Barger , M. S. Berger , R. J. N. Phillips

The helicity amplitudes for the process $\gamma \gamma \to A^0 A^0$ are studied to 1-loop order in the minimal SUSY (MSSM) model, where $A^0$ is the CP-odd Higgs particle. Simple exact analytic formulae are obtained, in terms of the $C_0$…

High Energy Physics - Phenomenology · Physics 2008-11-26 G. J. Gounaris , P. I. Porfyriadis