This study investigates the form factors and impact parameter space parton distribution functions of the rho meson derived from the generalized partondistributions within the Nambu-Jona-Lasinio model framework, emplo...
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This study investigates the form factors and impact parameter space parton distribution functions of the rho meson derived from the generalized partondistributions within the Nambu-Jona-Lasinio model framework, employing a proper time regularization scheme. We compare the charge , magnetic , and quadrupole form factors with lattice data. The dressed form factors, and , exhibit good agreement with lattice results;however, is found to be harder than what is observed in lattice calculations. The Rosenbluth cross section for elastic electron scattering on a spin-one particle can be expressed through the structure functions and . Additionally, the tensor polarization can also be formulated in terms of these form factors. We analyze the structure functions , and tensor polarization function;our findings quantitatively align with predicted values across various limits. In impact parameter space, we examine parton distribution functions along with their dependence on longitudinal momentum fraction x and impact parameter . The width distributions in impact parameter space reveal that the range of the charge distribution is the most extensive. In contrast, the transverse magnetic radius falls within a moderate range, while the quadrupole distribution demonstrates the narrowest extent.
parton distribution functions (PDFs) are important quantities in describing nucleon structures. They are universal and process-independent. As a matter of fact, nucleon PDFs are inevitably affected by nuclear matter d...
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parton distribution functions (PDFs) are important quantities in describing nucleon structures. They are universal and process-independent. As a matter of fact, nucleon PDFs are inevitably affected by nuclear matter during nuclear scattering process. In order to study the nuclear PDFs (nPDFs), in this paper, we introduce the nucleon pair PDFs (dPDFs) to describe partondistributions in the nucleon pair which is confined to a nucleus. We first of all construct the nuclear state in terms of the nucleonic states and calculate the operator definition of nPDFs. Neglecting the higher order corrections or multi-nucleon correlations, we find that nPDFs can be written as a sum of two terms which respectively correspond to PDFs and dPDFs. Nucleon pair PDFs which stem from nucleon-nucleon correlation are proportional to common nucleon PDFs but suppressed by a factor. Compared with the experimental data, we find that dPDFs can explain the behaviour of the EMC effect. We further calculate the Paschos-Wolfenstein ratio to study the nuclear matter effect on the extraction of weak mixing angle or sin2 theta W by using dPDFs.
PDFs of D-ee and D-e gamma types used for calculation of radiative corrections to electron energy spectrum in muon decay up to the order O(alpha L-3(2)) are presented. PDF approach is used to calculate radiative corre...
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PDFs of D-ee and D-e gamma types used for calculation of radiative corrections to electron energy spectrum in muon decay up to the order O(alpha L-3(2)) are presented. PDF approach is used to calculate radiative corrections.
The forward-backward asymmetry of the Drell-Yan process in dilepton decays at high invariant masses can be used to probe the parton distribution functions at large x. The behavior of three modern partondistribution f...
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The forward-backward asymmetry of the Drell-Yan process in dilepton decays at high invariant masses can be used to probe the parton distribution functions at large x. The behavior of three modern partondistribution function sets (CT18NNLO, MSHT20, and NNPDF4.0) are compared, and updated under various scenarios via epump using proton-proton collision pseudodata generated at s=13 TeV with 3000 fb−1 of integrated luminosity.
Perturbative solutions for unpolarized QED partondistribution and fragmentation functions are presented explicitly in the next-to-leading logarithmic approximation. The scheme of iterative solution of QED evolution e...
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Perturbative solutions for unpolarized QED partondistribution and fragmentation functions are presented explicitly in the next-to-leading logarithmic approximation. The scheme of iterative solution of QED evolution equations is described in detail. Terms up to (alpha 3L2) are calculated analytically, where L=ln(mu F2/me2) is the large logarithm which depends on the factorization energy scale mu F >> m e . The results are process independent and relevant for future high-precision experiments.
This study investigates the form factors and impact parameter space parton distribution functions of the p meson derived from the generalized partondistributions within the Nambu-Jona-Lasinio model framework,employin...
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This study investigates the form factors and impact parameter space parton distribution functions of the p meson derived from the generalized partondistributions within the Nambu-Jona-Lasinio model framework,employing a proper time regularization *** compare the charge G_(C),magnetic G_(M),and quadrupole G_(Q) form factors with latice *** dressed form factors,G_(C)^(D) and G_(M)^(D),exhibit good agreement with latice results;however,G_(Q)^(D) is found to be harder than what is observed in latice *** Rosenbluth cross section for elastic electron scattering on a spin-one particle can be expressed through the structure functions A(Q^(2))and B(Q^(2)).Additionally,the tensor polarization T_(20)(Q^(2),θ)can also be formulated in terms of these form *** analyze the structure functions A(Q2),B(Q2)and tensor polarization function T2o(Q2,);our findings quantitatively align with predicted values across various *** impact parameter space,we examine parton distribution functions along with their dependence on longitudinal momentum fraction x and impact parameter b+.The width distributions in impact parameter space reveal that the range of the charge distribution q_(C)(x,b_(⊥)^(2))is the most *** contrast,the transverse magnetic radius falls within a moderate range,while the quadrupole distribution q_(Q)(x,b_(⊥)^(2))demonstrates the narrowest extent.
We explore the application of a two-component model of proton structure functions in the analysis of deep-inelastic scattering (DIS) data at low Q(2) and small x. This model incorporates both vector meson dominance an...
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We explore the application of a two-component model of proton structure functions in the analysis of deep-inelastic scattering (DIS) data at low Q(2) and small x. This model incorporates both vector meson dominance and the correct photo-production limit. The CJ15 parameterization is applied to the QCD component, in order to take into account effects of order 1/Q(2) effects, such as target mass corrections and higher twist (HT) contributions. The parameters of the leading twist parton distribution functions (PDFs) and HT coefficient functions are determined by fitting DIS data. The second moments of the PDFs are extracted and compared with other global fits and lattice determinations.
In this work, the impact of recent measurements of heavy-flavour production in pp collisions on parton distribution functions (PDFs) and their uncertainties is studied. In this regard, the absolute and normalised cros...
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In this work, the impact of recent measurements of heavy-flavour production in pp collisions on parton distribution functions (PDFs) and their uncertainties is studied. In this regard, the absolute and normalised cross sections of beauty hadron production measured by LHCb at center-of-mass energy of 7 TeV and 13 TeV are separately included in the next-to-leading order (NLO) global QCD analysis together with the measurements of the inclusive and heavy-flavour production cross sections at HERA. It is illustrated that the heavy-flavour data of the LHCb experiment impose additional constraints on the PDFs, especially on the gluon distribution at low partonic fractions x of the proton momentum. One of the most important results of the present analysis is the significant reduction of the gluon uncertainties in the region less than x = 10(-4) that can play a crucial rule in many areas of high energy physics investigations. (C) 2018 Elsevier B.V. All rights reserved.
An important limitation in current fits of parton distribution functions (PDFs) is that PDF uncertainties do not include any source of theoretical uncertainty. Here we present a general method for incorporating theore...
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The recent measurement of the differential γ ＋ c-jet cross section, performed at the Tevatron collider in Run II by the D0 collaboration, is studied in a next-to-leading order（NLO） global QCD analysis to assess it...
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The recent measurement of the differential γ ＋ c-jet cross section, performed at the Tevatron collider in Run II by the D0 collaboration, is studied in a next-to-leading order（NLO） global QCD analysis to assess its impact on the proton parton distribution functions（PDFs）. We show that these data lead to a significant change in the gluon and charm quark distributions. We demonstrate also that there is an inconsistency between the new high precision HERA I＋II combined data and Tevatron measurement. Moreover, in this study we investigate the impact of older EMC measurements of charm structure function F_c^2 on the PDFs and compare the results with those from the analysis of Tevatron data. We show that both of them have the same impact on the PDFs, and thus can be recognized as the same evidence for the inefficiency of perturbative QCD in dealing with charm production in some kinematic regions.
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