# Kaon Multiplicities of Semi-inclusive DIS and the Fragmentation Functions

## TL;DR

This paper investigates the discrepancy in charged kaon multiplicities from HERMES and COMPASS experiments, analyzing fragmentation functions and finding that existing models do not fully explain the differences.

## Contribution

It critically examines the empirical fragmentation functions and highlights limitations in current theoretical estimates regarding kaon multiplicities.

## Key findings

- Discrepancy between HERMES and COMPASS data cannot be attributed to $Q^2$ differences.
- DSS2017 fragmentation functions show less agreement with HERMES data than previously claimed.
- Current models need refinement to accurately describe kaon production in semi-inclusive DIS.

## Abstract

There is an apparent discrepancy between the results of the charged kaon multiplicities off the deuteron target from HERMES and COMPASS experiments. In this article we point out that this discrepancy cannot be explained by different $Q^2$ values. Furthermore we examine the empirical parametrization of the fragmentation functions, DSS2017 carefully and find that the agreement between the theoretical estimate and the HERMES data is less satisfactory as claimed.