A detailed study of charm content of a proton in the frameworks of the Kimber-Martin-Ryskin and Martin-Ryskin-Watt approaches

TL;DR

This paper calculates the charm structure function of the proton using $k_t$-factorization with UPDFs from KMR and MRW methods, comparing results with experimental data and other models to validate the approaches.

Contribution

It introduces a detailed calculation of $F_2^{c\overline{c}}(x, Q^2)$ using KMR and MRW UPDFs within the $k_t$-factorization framework, showing consistency with data and other theories.

Findings

Calculated charm structure functions agree with experimental data.

KMR and MRW UPDF schemes produce consistent results.

The approach aligns with other theoretical models.

Abstract

The charm structure function, ($F_2^{c\overline{c}}(x, Q^2)$), is calculated in the framework of the $k_t$-factorization formalism by using the unintegrated parton distribution functions (UPDF), which are generated through the Kimber et al. (KMR) and Martin et al. (MRW) procedures. The Martin group (MMHT2014) parton distribution functions (PDF) is used as the input PDF for the corresponding UPDF. The resulted $F_2^{c\overline{c}}(x, Q^2)$ is compared with the predicted data and the calculations given by the ZEUS and H1 collaborations, the parton pQCD theory, i.e. the general-mass variable-flavour-number scheme (GMVFNS), the LO collinear procedure and the saturation model introduced by Golec-Biernat and W\"usthoff (GBW), respectively. In general, it is shown that the calculated charm structure functions based on the stated above two UPDF schemes are consistent with the experimental data and other theoretical predictions. Also, a short discussion is presented regarding the KMR and MRW UPDF behaviors.