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Related papers: Instanton Distribution in Quenched and Full QCD

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We explain how nonperturbative effects can be systematically included when constructing an effective field theory. We concentrate in particular on the matching calculation, by which a low energy theory without a heavy particle degree of…

High Energy Physics - Phenomenology · Physics 2009-09-11 Howard Georgi , Samuel T. Osofsky

We suggest a constrained instanton (CI) solution in the physical QCD vacuum which is described by large-scale vacuum field fluctuations. This solution decays exponentially at large distances. It is stable only if the interaction of the…

High Energy Physics - Phenomenology · Physics 2011-09-13 A. E. Dorokhov , S. V. Esaibegyan , A. E. Maximov , S. V. Mikhailov

We describe quenched spectroscopy in SU(2) gauge theory using smoothed gauge field configurations. We investigate the properties of quarks moving in instanton background field configurations, where the sizes and locations of the instantons…

High Energy Physics - Lattice · Physics 2009-10-30 Thomas DeGrand , Anna Hasenfratz , Tamas G. Kovacs

Instanton effects can give large contribution to strong interacting processes, especially at the energy scale where perturbative QCD is no longer valid. However instanton contribution to the gluon contribution in constituent quark and…

High Energy Physics - Phenomenology · Physics 2018-08-01 Baiyang Zhang , Nikolai Kochelev , Hee-Jung Lee , Pengming Zhang

We pursue the intriguing possibility that larger-size instantons build up diffractive scattering, with the marked instanton-size scale $<\rho> \approx 0.5$ fm being reflected in the conspicuous ``geometrization'' of soft QCD. As an explicit…

High Energy Physics - Phenomenology · Physics 2007-05-23 F. Schrempp , A. Utermann

Three-dimensional lattice QCD is studied by Monte Carlo simulations within the quenched approximation. At zero temperature a quark-antiquark condensate is observed in the limit of vanishing quark masses. The condensate vanishes continuously…

High Energy Physics - Lattice · Physics 2009-10-31 P. H. Damgaard , U. M. Heller , A. Krasnitz , T. Madsen

An up-to-date global QCD analysis of high energy lepton-hadron and hadron-hadron interactions is performed to better determine the gluon and quark parton distributions in the nucleon. Improved experimental data on inclusive jet production,…

High Energy Physics - Phenomenology · Physics 2008-11-26 H. L. Lai , J. Huston , S. Kuhlmann , J. Morfin , F. Olness , J. F. Owens , J. Pumplin , W. K. Tung

Nucleon-nucleon scattering is studied to next-to-leading order in a partially-quenched extension of an effective field theory used to describe multi-nucleon systems in QCD. The partially-quenched nucleon-nucleon amplitudes will play an…

High Energy Physics - Lattice · Physics 2009-11-07 Silas R. Beane , Martin J. Savage

The cooling effects of a quantum LC circuit coupled inductively with an ensemble of artificial qubits are investigated. The particles may decay independently or collectively through their interaction with the environmental vacuum…

Quantum Physics · Physics 2015-05-18 Mihai A. Macovei

The contribution of instanton-induced effective inter-quark interactions to the baryon mass splittings was considered in the bag model. It is found that results are different from those obtained in the constituent quark model where the…

High Energy Physics - Phenomenology · Physics 2009-10-22 D. Klabučar

Canonical instanton theory is a widespread approach to describe the dynamics of chemical reactions in low temperature environments when tunneling effects become dominant. It is a semiclassical theory which requires locating classical…

Chemical Physics · Physics 2020-09-15 Andreas Löhle , Johannes Kästner

An instanton method is proposed to investigate the quantum tunneling between two weakly-linked Bose-Einstein condensates confined in double-well potential traps. We point out some intrinsic pathologies in the earlier treatments of other…

Mesoscale and Nanoscale Physics · Physics 2016-08-31 Yunbo Zhang , H. J. W. Müller-Kirsten

We are considering the modifications of gluon properties in Instanton Liquid Model (ILM) for the QCD vacuum. Re-scattering of a gluons on an instantons leads to the dynamical momentum-dependent gluon mass $M_g(q).$ First, we considered…

High Energy Physics - Phenomenology · Physics 2018-02-07 M. Musakhanov , O. Egamberdiev

The quantum behavior of a precooled cantilever can be probed highly efficiently by coupling to a trapped ultracold ion, in which a fast cooling of the cantilever down to the ground vibrational state is possible. We solve the dynamics of the…

Quantum Physics · Physics 2007-05-23 T. Liu , M. Feng , K. L. Wang

The instanton--antiinstanton pair induced asymptotics of perturbation theory expansion for QCD correlators is considered. It is argued that though the true asymptotics is dominated by renormalon, the instanton-induced contribution may…

High Energy Physics - Phenomenology · Physics 2009-10-28 P. G. Silvestrov

We consider the instanton contributions for the production of a gluon jet with large transverse momentum in QCD. We find that Mueller's corrections corresponding to the rescattering of hard quanta are likely to remove contributions of large…

High Energy Physics - Phenomenology · Physics 2009-10-28 I. I. Balitsky , V. M. Braun

Quenching and annealing are extreme opposites in the time evolution of a quantum system: Annealing explores equilibrium phases of a Hamiltonian with slowly changing parameters and can be exploited as a tool for solving complex optimization…

Quantum Physics · Physics 2022-01-19 Bernhard Irsigler , Tobias Grass

We study instantons in QCD with many colors. We first discuss a number of qualitative arguments concerning the large N_c scaling behavior of a random instanton ensemble. We show that most hadronic observables are compatible with standard…

High Energy Physics - Phenomenology · Physics 2009-11-07 Thomas Schaefer

We study isospin breaking instanton corrections to the operator product expansion of the nucleon correlation functions. After a comparison with quark model calculations based on the 't Hooft interaction, we examine the role of instantons in…

High Energy Physics - Phenomenology · Physics 2014-11-17 Hilmar Forkel , Marina Nielsen

We investigate the topological properties of $N_f = 2+1$ QCD with physical quark masses, both at zero and finite temperature. We adopt stout improved staggered fermions and explore a range of lattice spacings $a \sim 0.05 - 0.12$ fm. At…