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Related papers: Decoupling in QED and QCD

200 papers

The top flavour-changing neutral couplings can be large in extended models with vector-like quarks. In the next decade(s) the CERN Large Hadron Collider will allow to measure (bound) them with a precision of few per cent.

High Energy Physics - Phenomenology · Physics 2011-03-02 F. del Aguila

Contents: 1. The Thermodynamics of Quarks and Gluons 2. Hard Probes: Colour Deconfinement 3. Electromagnetic Probes: Chiral Symmetry Restoration 4. Soft Probes: Equilibration and Expansion 5. Conclusions

High Energy Physics - Phenomenology · Physics 2007-05-23 Helmut Satz

We report our progress in combining a two-level sampling algorithm with distillation techniques for calculations of disconnected diagrams in quenched QCD. The simulations are performed on a single ensemble at $\beta=6.0$ and volume…

High Energy Physics - Lattice · Physics 2025-01-31 Lorenzo Barca , Jacob Finkenrath , Francesco Knechtli , Michael Peardon , Stefan Schaefer , Juan Andrés Urrea-Niño

We consider a two-photon quantum model of radiation-matter interaction between a single two-level atom and a degenerate bimodal high-Q cavity field. Within this tripartite system the explicit construction of two collective radiation modes,…

Quantum Physics · Physics 2015-06-12 M. Guccione , M. A. Jivulescu , A. Messina

We present results of a simulation of 2 flavour QCD on a $16^3\times4$ lattice using p4-improved staggered fermions with bare quark mass $m/T=0.4$. Derivatives of the thermodynamic grand canonical partition function $Z(V,T,\mu_u,\mu_d)$…

High Energy Physics - Phenomenology · Physics 2016-08-16 S. Ejiri , C. R. Allton , M. Döring , S. J. Hands , O. Kaczmarek , F. Karsch , E. Laermann , K. Redlich

One-loop QED corrections to the differential width of radiative muon decay are considered. Results can be used to analyze high statistics data of modern and future experiments.

High Energy Physics - Phenomenology · Physics 2009-11-10 A. B. Arbuzov , E. S. Scherbakova

We present our progress report on 1+1+1 flavor QCD+QED simulation at the physical point. Calculations are carried out with 2+1 flavor QCD gauge configurations generated by the PACS-CS Collaboration. The dynamical QED effect and the up-down…

High Energy Physics - Lattice · Physics 2019-08-14 N. Ukita

We discuss the phase structure and fluctuations of conserved charges in two flavor QCD. The importance of the density fluctuations to probe the existence of the critical end point is summarized. The role of these fluctuations to identify…

High Energy Physics - Phenomenology · Physics 2008-11-26 K. Redlich , B. Friman , C. Sasaki

Method of calculating hadron multi-point functions and disconnected quark loop contributions which are not readily accessible through conventional techniques is proposed. Results are reported for pion-pion, pion-nucleon and nucleon-nucleon…

High Energy Physics - Lattice · Physics 2009-10-22 Y. Kuramashi , M. Fukugita , H. Mino , M. Okawa , A. Ukawa

Massive two-flavor QED_2 is known to have many similarities to the two-flavor QCD_4. Here we compare the \pi-\pi scattering amplitudes (actually an analog process in QED_2) of the two theories. The QED_2 amplitude is computed from the…

High Energy Physics - Phenomenology · Physics 2009-10-31 D. Delphenich , J. Schechter , S. Vaidya

The analytical result for the six-photon helicity amplitudes in scalar QED is presented. To compute the loop, a recently developed method based on multiple cuts is used. The amplitudes for QED and $QED^{\caln=1}$ are also derived using the…

High Energy Physics - Phenomenology · Physics 2009-11-18 C. Bernicot , J. -Ph. Guillet

We introduce a new color decomposition for multi-parton amplitudes in QCD, free of fundamental-representation matrices and structure constants. This decomposition has a physical interpretation in terms of the flow of color, which makes it…

High Energy Physics - Phenomenology · Physics 2009-11-07 F. Maltoni , K. Paul , T. Stelzer , S. Willenbrock

We describe how the general mechanism of partial deconfinement applies to large-$N$ QCD and the partially-deconfined phase inevitably appears between completely-confined and completely-deconfined phases. Furthermore, we propose how the…

High Energy Physics - Lattice · Physics 2023-12-29 Masanori Hanada , Hiroki Ohata , Hidehiko Shimada , Hiromasa Watanabe

We report a new analysis of the isospin splittings within the decuplet baryon spectrum. Our numerical results are based upon five ensembles of dynamical QCD+QED lattices. The analysis is carried out within a flavour-breaking expansion which…

High Energy Physics - Lattice · Physics 2019-09-05 R. Horsley , Z. Koumi , Y. Nakamura , H. Perlt , D. Pleiter , P. E. L. Rakow , G. Schierholz , A. Schiller , H. Stüben , R. D. Young , J. M. Zanotti

We present the decomposition of QCD partial amplitudes into primitive amplitudes at one-loop level and tree level for arbitrary numbers of quarks and gluons. Our method is based on shuffle relations. This method is purely combinatorial and…

High Energy Physics - Phenomenology · Physics 2014-07-09 Christian Reuschle , Stefan Weinzierl

A dipole picture of high energy scattering is developed in the 2+1 dimensional QCD, following Mueller. A generalized integral equation for the dipole density with a given separation and center of mass position is derived, and meson-meson…

High Energy Physics - Phenomenology · Physics 2016-08-24 Miao Li , Chung-I Tan

We present the two-loop virtual QCD corrections to the production of heavy quarks in gluon fusion. The results are exact in the limit when all kinematical invariants are large compared to the mass of the heavy quark up to terms suppressed…

High Energy Physics - Phenomenology · Physics 2010-04-05 M. Czakon , A. Mitov , S. Moch

We present a ``toy'' model for breaking supersymmetric gauge theories at the effective Lagrangian level. We show that it is possible to achieve the decoupling of gluinos and squarks, below a given supersymmetry breaking scale m, in the…

High Energy Physics - Theory · Physics 2009-10-31 Francesco Sannino

In this lecture, after recalling the basic definitions and facts about the running coupling in QCD, I present a critical discussion of the methods for measuring $\alpha_s$ and select those that appear to me as the most reliably precise

High Energy Physics - Phenomenology · Physics 2013-03-26 Guido Altarelli

Light-cone QCD sum rules are employed to compute the strong coupling constants: g_{B^* B^* pi}, g_{B_1 B_0 pi} and g_{B_1 B^* pi}, where (B,B^*) and (B_0,B_1) are negative and positive parity (0^-,1^-) and (0^+,1^+) \bar qQ doublets. The…

High Energy Physics - Phenomenology · Physics 2008-11-26 P. Colangelo , F. De Fazio