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Nonperturbative and higher order perturbative effects in deep inelastic $ u_tau/bar u_tau-$nucleon scattering

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 نشر من قبل Mohammad Athar SAJJAD
 تاريخ النشر 2020
  مجال البحث
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The effect of nonperturbative and higher order perturbative corrections to all the free nucleon structure functions ($F_{iN}(x,Q^2); i=1-5$) in the DIS of $ u_tau/{bar u}_tau$ on nucleon is studied. The target mass correction (TMC) and higher twist (HT) effects are incorporated following the works of Kretzer et al. and Dasgupta et al., respectively. The evaluation of the nucleon structure functions has been performed by using the MMHT 2014 parameterization of the parton distribution functions (PDFs). The calculations have been performed at the next-to-leading(NLO) order. These nucleon structure functions (SF) are used to calculate the DIS cross section by further including the kinematical corrections due to $tau$-lepton mass. Due to the inclusion of lepton mass two additional structure functions $F_{4N}(x,Q^2)$ and $F_{5N}(x,Q^2)$ become non-negligible. The results for the nucleon structure functions, differential and total scattering cross sections are presented. The various effects considered in this work are effective in the different regions of $x$ and $Q^2$, and quite important in the energy region of $E_{ u_tau/{bar u}_tau} < 15$ GeV. A comparative study of our results with the existing results in the literature for the cross sections is made in the energy region of interest for the DUNE, SHiP, DsTau and HyperK experiments proposed to be done in the near future.



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