Results 101 to 110 of about 152,251 (236)

THE TRANSITION BETWEEN PERTURBATIVE AND NON-PERTURBATIVE QCD [PDF]

Quark-Hadron Duality and the Transition to PQCD, 2006
We study both polarized and unpolarized proton structure functions in the kinematical region of large Bjorken x and four-momentum transfer of few GeV^2. In this region the phenomenon of parton-hadron duality takes place between the smooth continuation of the deep inelastic scattering curve and the average of the nucleon resonances.
A. Fantoni, Simonetta Liuti
openaire   +4 more sources

Higgs‐induced screening mechanisms in scalar‐tensor theories

Annals of the New York Academy of Sciences, Volume 1531, Issue 1, Page 95-103, January 2024.
Abstract We consider the theory of a light conformally coupled scalar field, that is, one that is coupled directly to the Ricci scalar of the gravitational sector. This theory can be written equivalently as one of a light scalar that is coupled to the Standard Model of particle physics with a particular combination of Higgs‐portal couplings.
Clare Burrage, Peter Millington
wiley   +1 more source

The Infrared Boundary of Perturbative QCD [PDF]

arXiv, 2001
Evidence is reviewed suggesting that QCD remains a perturbative theory with a (relatively) small coupling constant down to a distinct infrared boundary on perturbative physics, a boundary corresponding to the momentum scale associated with a beta-function pole.
arxiv  

Role of Time‐Varying Magnetic Field on QGP Equation of State

Advances in High Energy Physics, Volume 2024, Issue 1, 2024.
The phase diagram of quantum chromodynamics (QCD) and its associated thermodynamic properties of quark‐gluon plasma (QGP) are studied in the presence of time‐dependent magnetic field. The study plays a pivotal role in the field of cosmology, astrophysics, and heavy‐ion collisions. In order to explore the structure of quark‐gluon plasma to deal with the
Yogesh Kumar, Poonam Jain, Pargin Bangotra, Vinod Kumar, D. V. Singh, S. K. Rajouria, Bhartendu K. Singh   +6 more
wiley   +1 more source

Perturbative and non-perturbative QCD

, 2006
In these lectures we give a concise introduction to the ideas of renormalon calculus in QED and QCD. We focus in particular on the example of the Adler D function of vacuum polarization, and on relations between perturbative renormalon ambiguities and corresponding non-perturbative Operator Product Expansion (OPE) ambiguities.
openaire   +2 more sources

Revisiting $$B\rightarrow K^*\pi $$ B → K ∗ π and $$B\rightarrow K\rho $$ B → K ρ decays using the modified perturbative QCD approach

European Physical Journal C: Particles and Fields
We revisit $$B\rightarrow K^*\pi $$ B → K ∗ π and $$B\rightarrow K\rho $$ B → K ρ decay processes using the modified perturbative QCD approach, which is developed based on the perturbative QCD approach with a few improvements.
Ru-Xuan Wang, Mao-Zhi Yang
doaj   +1 more source

Lattice QCD Method To Study Proton Spin Crisis [PDF]

arXiv, 2019
The proton spin crisis remains an unsolved problem in particle physics. The spin and angular momentum of the partons inside the proton are non-perturbative quantities in QCD which cannot be calculated by using the perturbative QCD (pQCD). In this paper we present the lattice QCD formulation to study the proton spin crisis.
arxiv  

Solving Schrödinger Wave Equation for the Charmonium Spectrum Using Artificial Neural Networks

Advances in High Energy Physics, Volume 2024, Issue 1, 2024.
In this study, we solved the Schrödinger wave equation by using effective potential in an artificial neural network (ANN) for the mass spectrum of different charmonium states, including ηc, ψ2, χ2, and χ4. The ANN approach provides an efficient, more general, and continuous solution‐approximating strategy, thus eliminating the possibility of skipping ...
Tariq Mahmood, Jumanah Ahmed Darwish, Talab Hussain, Maqsood Ahmed, Rehan Ahmad Khan Sherwani, John Strologas   +5 more
wiley   +1 more source

Foundations of Perturbative QCD

, 2011
The most non-trivial of the established microscopic theories of physics is QCD: the theory of the strong interaction. A critical link between theory and experiment is provided by the methods of perturbative QCD, notably the well-known factorization theorems.
openaire   +2 more sources

On the description of exotic hadron states within QCD sum rules

EPJ Web of Conferences, 2017
Revisiting the QCD sum-rule description of exotic hadron states, we argue that, in order to arrive at trustable analyses of, for instance, strong decay widths of multiquarks, it is inevitable to adopt the QCD sum-rule approach beyond the leading ...
Lucha Wolfgang, Melikhov Dmitri
doaj   +1 more source