# The EMC ratios of $^4He$, $^3He$ and $^3H$ nuclei in the $k_t$ factorization framework using the Kimber-Martin-Ryskin unintegrated parton distribution functions

## TL;DR

This study calculates the EMC ratios of helium and tritium nuclei using the $k_t$-factorization framework with Kimber-Martin-Ryskin unintegrated parton distribution functions, showing good agreement with experimental data especially at small $x$ values.

## Contribution

It introduces a method to compute nuclear EMC ratios using $k_t$-factorization and KMR UPDFs derived from constituent quark exchange model PDFs, improving agreement at small $x$.

## Key findings

- Good agreement with experimental EMC ratios.
- Enhanced accuracy at small $x$ compared to previous models.
- The $k_t$ dependence captures shadowing effects.

## Abstract

The unintegrated parton distribution functions (UPDFs) of $^3H$, $^3He$ and $^4He$ nuclei are generated to calculate their structure functions (SFs) in the $k_t$-factorization approach. The Kimber-Martin-Ryskin (KMR) formalisn is applied to evaluate the double-scale UPDFs of these nuclei from their single-scale parton distribution functions (PDFs), which can be obtained from the constituent quark exchange model (CQEM). Afterwards, these SFs are used to calculate the European Muon Collaboration (EMC) ratios of these nuclei. The resulting EMC ratios are then compared with the available experimental data and good agreement with data is achieved. In comparison with our previous EMC ratios, in which the conventional PDFs were used in the calculations, the accord of the present outcomes with experiment at the small $x$ region becomes impressive. Therefore, it can be concluded that the $k_t$ dependence of partons can reproduce the general form of the shadowing effect at the small $x$ values in above nuclei.