English
Related papers

Related papers: The QCD analysis of xF_3 structure function based …

200 papers

In this paper we show that, as in the spacelike case, the inverse logarithmic expansion is applicable for all values of the argument of the analytic coupling constant. We present two different approaches, one of which is based primarily on…

High Energy Physics - Phenomenology · Physics 2023-06-07 A. V. Kotikov , I. A. Zemlyakov

Analytic versions of QCD are those whose coupling alpha_s(Q^2) does not have the unphysical Landau singularities on the space-like axis (-q^2=Q^2 > 0). The coupling is analytic in the entire complex plane except the time-like axis (Q^2 <…

High Energy Physics - Phenomenology · Physics 2008-12-18 Gorazd Cvetic , Cristian Valenzuela

We summarize recent results on the evolution of unpolarized parton densities and deep-inelastic structure functions in massless perturbative QCD. Due to last year's extension of the integer-moment calculations of the three-loop splitting…

High Energy Physics - Phenomenology · Physics 2008-11-26 W. L. van Neerven , A. Vogt

We present a first QCD analysis of next-to-next-leading-order (NNLO) contributions of the spin-dependent parton distribution functions (PPDFs) in the nucleon and their uncertainties using the Jacobi polynomial approach. Having the NNLO…

High Energy Physics - Phenomenology · Physics 2016-06-24 F. Taghavi Shahri , Hamzeh Khanpour , S. Atashbar Tehrani , Z. Alizadeh Yazdi

The removal of unphysical singularities in the perturbatively calculable part of the pion form factor--a classic example of a three-point function in QCD--is discussed. Different ``analytization'' procedures in the sense of Shirkov and…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. P. Bakulev , A. I. Karanikas , N. G. Stefanis

A detailed next-to-next-to-leading order (NNLO) QCD analysis is performed for the experimental data of the CCFR collaboration for the $xF_3$ structure function. Theoretical ambiguities of the results of our NNLO fits are estimated by…

High Energy Physics - Phenomenology · Physics 2009-10-31 A. L. Kataev , G. Parente , A. V. Sidorov

By working in QED, we obtain the electron, positron, and photon Parton Distribution Functions (PDFs) of the unpolarised electron at the next-to-leading logarithmic accuracy. The PDFs account for all of the universal effects of initial-state…

High Energy Physics - Phenomenology · Physics 2022-07-26 V. Bertone , M. Cacciari , S. Frixione , G. Stagnitto

The two-loop invariant (running) coupling of QCD is written in terms of the Lambert W function. The analyticity structure of the coupling in the complex Q^2-plane is established. The corresponding analytic coupling is reconstructed via a…

High Energy Physics - Phenomenology · Physics 2016-12-28 B. Magradze

The structure of the QFT expansion is studied in the framework of a new "Invariant analytic" version of the perturbative QCD. Here, an invariant (running) coupling $a(Q^2/\Lambda^2)=\beta_1\alpha_s(Q^2)/4\pi$ is transformed into a…

High Energy Physics - Theory · Physics 2014-11-18 D. V. Shirkov

We compute the coefficient function for the charge-averaged W^(+/-)-exchange structure function F_3 in deep-inelastic scattering (DIS) to the third order in massless perturbative QCD. Our new three-loop contribution to this quantity forms,…

High Energy Physics - Phenomenology · Physics 2010-04-05 S. Moch , J. Vermaseren , A. Vogt

A non-singlet QCD analysis of the structure function $xF_3$ up to NNLO is performed based on the Bernstein polynomials approach. We use recently calculated NNLO anomalous dimension coefficients for the moments of the $xF_3$ structure…

High Energy Physics - Phenomenology · Physics 2010-10-27 Ali N. Khorramian , S. Atashbar Tehrani

Quark-hadron duality is studied in a systematic way for both the unpolarized and polarized structure functions, by taking into account all the available data in the resonance region.In both cases, a detailed perturbative QCD based analysis…

High Energy Physics - Phenomenology · Physics 2009-11-11 A. Fantoni , N. Bianchi , S. Liuti

We have computed the complete next-to-next-to-leading order (NNLO) contributions to the splitting functions governing the evolution of unpolarized parton densities in perturbative QCD. Our results agree with all partial results available in…

High Energy Physics - Phenomenology · Physics 2009-11-10 S. Moch , J. A. M. Vermaseren , A. Vogt

Using recent and updated world data on polarized structure functions $g_1$ and $g_2$ we perform QCD analysis at the next-next-to-leading-order (NNLO) accuracy. We include also target mass correction and higher twist effect to get more…

High Energy Physics - Phenomenology · Physics 2022-04-26 Abolfazl Mirjalili , Shahin Atashbar Tehrani

We briefly summarize the outcomes of our recent improved fits to the experimental data of CCFR collaboration for $xF_3$ structure function of $\nu N$ deep-inelastic scattering at the next-to-next-to-leading order. Special attention is paid…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. L. Kataev , G. Parente , A. V. Sidorov

As a first step towards the complete calculation of deep-inelastic scattering at third order of massless perturbative QCD, we have computed the fermionic (nf) contributions to the flavour non-singlet structure functions in unpolarized…

High Energy Physics - Phenomenology · Physics 2009-11-07 J. A. M. Vermaseren , S. Moch , A. Vogt

The polarized nucleon structure function in the nonsinglet case is investigated here by a new insight rather than conventional perturbative QCD (pQCD). For this purpose we note that the solution of the evolution equations in moment space…

High Energy Physics - Phenomenology · Physics 2019-12-12 Leila Ghasemzadeh , Abolfazl Mirjalili , S. Atashbar Tehrani

We analyze experimental data for the production of Lambda baryons in e^+e^- annihilation in terms of scale dependent, QCD evolved, Lambda fragmentation functions. Apart from the vast majority of the data for which the polarization of an…

High Energy Physics - Phenomenology · Physics 2009-10-30 D. de Florian , M. Stratmann , W. Vogelsang

In this work, using the Laplace transformation technique we present our results for non-singlet quark distributions as well as nucleon structure function $F_2(x,Q^2)$ in unpolarized case at next-to-next-to-leading order (NNLO) QCD accuracy.…

High Energy Physics - Phenomenology · Physics 2020-06-09 Maral Salajegheh , S. Mohammad Moosavi Nejad , Abolfazl Mirjalili , S. Atashbar Tehrani

We present an overview of fractional analytic QCD beyond leading order, following the results recently obtained in Ref. [1]. We demonstrate four different representations, the details of their derivation, and show the applicability of…

High Energy Physics - Phenomenology · Physics 2022-07-05 A. V. Kotikov , I. A. Zemlyakov