Nonsinglet polarized nucleon structure function in infrared-safe QCD

Ghasemzadeh, Leila; Mirjalili, A.; Tehrani, S. Atashbar

doi:10.1103/physrevd.100.114017

Cited by 8 publications

(3 citation statements)

References 88 publications

(170 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…approach can be considered at infrared fixed point where QCD β-function is considered to be zero [38][39][40]. This subject is also interesting to be investigated from the other literature points of view like the infrared safe mode of QCD [41] or the Ads/CFT [42] and would be valuable to follow it as our further research activity.…”

mentioning

confidence: 99%

Comparing optimized renormalization schemes for QCD observables

Akrami

Mirjalili

2020

Phys. Rev. D

Self Cite

View full text Add to dashboard Cite

In this article based on the McKeon et al . approach, it can be shown that the renormalization group equation while it is related to the radiatively mass scale µ, operates to do a summation over QCD perturbative terms. Employing the full QCD β-function within this summation, all logarithmic corrections can be presented as the log-independent contributions. In another step of this approach , the renormalization scheme dependence for QCD observable which is characterised by Stevenson, can be examined by specifying the renormalization scheme in which the β-function beyond two-loop orders is utilized. In this regard two choices of renormalization schemes would be exposed. In one of them the QCD observable is expressed while involves two powers of running coupling constant such that the perturbative series contains just two terms. In another choice the perturbative series expansion is written as an infinite series in terms of two-loop running coupling which can be presented by Lambert W -function. In both cases the QCD observable involves parameters which are renormalization scheme invariant and the coupling constant which is independent of renormalization scale. We then consider the other approach which is called the complete renormalization group improvement (CORGI). In this approach, using the self consistency principle it is possible to reconstruct the conventional perturbative series in terms of scheme invariant quantities and the coupling constant as a function of Lambert-W function. It should be noted while in the renormalization group summation method of McKeon et al ., scheme dependence of observables is investigated separately from their scale dependence, in CORGI approach, through the principle of self consistency, both scale and scheme parameters are utilized together. In continuation we examine numerically these two approaches, considering two QCD observable. The first one is R e + e − ratio, investigated at three different colliding energies and the second observable is Higgs decay width to gluon-gluon. Comparison for R e + e − with the available experimental is done. The results based on the McKeon et al . approach are in better agreement with the experimental data.

show abstract

mentioning

confidence: 99%

Comparing optimized renormalization schemes for QCD observables

Akrami

Mirjalili

2020

Phys. Rev. D

Self Cite

View full text Add to dashboard Cite

show abstract

“…This coupling defines a version of (A)QCD which has several attractive features: 1) exp . Other holomorphic couplings have been introduced and applied in QCD phenomenology by various authors, among them [23][24][25][26][27][28][29][30][31][32][33][34][35][36]. Further, spacelike QCD observables can be evaluated also by applying dispersive methods directly to them [37][38][39][40][41][42][43][44].…”

Section: Discussionmentioning

confidence: 99%

Infrared-suppressed QCD coupling and the hadronic contribution to muon g-2

Cvetič¹,

Kögerler²

2020

J. Phys. G: Nucl. Part. Phys.

View full text Add to dashboard Cite

A variant of QCD with the coupling suppressed in the infrared (IR) regime, as suggested by large-volume lattice calculations of the Landau-gauge gluon and ghost dressing functions, is considered. The coupling is further restricted by the condition of approximate coincidence with perturbative QCD in the high momentum regime, and by the τ-lepton semihadronic decay rate in the intermediate momentum regime, the rate which is evaluated by a renormalon-motivated resummation method. The obtained coupling turns out to be free of Landau singularities. The D = 4, 6 condensate values of the Adler function are then extracted by application of the Borel sum rules to the OPAL and ALEPH (V+A)-channel data of τ-decay, and the corresponding V-channel condensate values are deduced as well. We then show that the correct value of the hadronic vacuum polarization contribution to the muon anomalous magnetic moment, a had(1) µ , is reproduced by regularizing the D = 4, 6 OPE terms in the V-channel Adler function with IR-regularization masses M D/2 1 GeV, suggesting the internal consistency of the presented QCD framework.

show abstract

“…We use the last one to shift and even eliminates the mentioned singularities in calculations of physical quantities such as unpolarized nucleon structure function (NSF) and also the Gottfried sum rule, and thus modify their theoretical predictions. We refer to [10] for recent related work. In this approach, the running QCD coupling constant (a(Q 2 ) = αs(Q 2 ) π ) is transformed in an analytic function of Q 2 (analytic for Q 2 < 0) which is called analytic QCD coupling constant [A 1 (Q 2 )] that does not have any Landau singularities and we are able to calculate the results for the quantities without any such singularities at the low energies, using the analytic coupling constant.…”

Section: Introductionmentioning

confidence: 99%

Analytical perturbation theory and Nucleon structure function in infrared region

Ghasemzadeh,

Mirjalili,

Tehrani

2021

Preprint

Self Cite

View full text Add to dashboard Cite

We employ analytic QCD (anQCD) approach to analyze the unpolarized nucleon structure function (NSF) in deep inelastic scattering ( DIS ) processes at the next-to-leading order (NLO) accuracy. Considering the unreliable results of underlying perturbative QCD (pQCD) at energy scale Q 2 ∼ Λ 2 and even less we modify the calculations at these scales using anQCD approach and compare them with results from underlying pQCD and also with the available experimental data. In these progresses the massive perturbation theory (MPT) model is also used where an effective mass is attributed to gluons. We finally use the Jacobi polynomials formalism to transfer the calculations from Mellin moment space to Bjorken-x space. To confirm the validity of anQCD approach the Gottfired sum rule is also investigated. The achieved numerical results at low energy scales are compatible with what is expected and corresponding to an admissible behaviour of parton densities.

show abstract

Nonsinglet polarized nucleon structure function in infrared-safe QCD

Cited by 8 publications

References 88 publications

Comparing optimized renormalization schemes for QCD observables

Comparing optimized renormalization schemes for QCD observables

Infrared-suppressed QCD coupling and the hadronic contribution to muon g-2

Analytical perturbation theory and Nucleon structure function in infrared region

Contact Info

Product

Resources

About