Consistency Check of Charged Hadron Multiplicities and Fragmentation Functions in SIDIS

Abstract

We derived the conditions on certain combinations of integrals of the fragmentation functions of pion using HERMES data for the sum of the charged pion multiplicities from semi-inclusive deepinelastic scattering (SIDIS) off the deuteron target. We have chosen several FFs to study the ratios of the strange PDFs S (x) and the nonstrange PDFs Q(x, Q 2 ) extracted from the charged pion and kaon multiplicities. We conclude that, in the LO QCD analysis and with the D π,K Q,S (Q 2 ) of the FFs chosen in our study, there is inconsistency between S (x, Q 2 )/Q(x, Q 2 ) derived from the pion and kaon multiplicity data.Finally, we demonstrate that the HERMES pion multiplicity data are unlikely to be compatible with two widely-used PDFs, namely CTEQ6L and leading order NNPDF3.0.