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چکیده
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Recent measurements of top quark pair production cross-section, which is performed at the LHC and the Tevatron collider, are studied using Hessian profiling technique to obtain their impact on the parton distribution functions (PDFs). The top quark production data covers different center-of-mass energies s = 1.96, 5.02, 7, 8 and 13 TeV in either pp or pp̄ collisions. It is explained how the Hessian profiling method may be used to assess the impact of these new data on PDFs and consequently on their predictions. In this research, the impact of recent measurements of top quark pair cross-sections on different CT14, MMHT2014 and NNPDF3.0 PDF sets is investigated. The analysis results show that the recent top quark production at the LHC and Tevatron data provide significant constraints in particular on the central value, relative uncertainties or both for the s-quark distribution and the gluon PDFs in both CT14 and MMHT2014 PDF sets and are insensitive to valence-quark PDFs. A small constraint on the ū-sea quark distribution for CT14 PDF is also observed. There is no impact on the NNPDF3.0 PDF set in presence of these data.
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