JAM global QCD analysis of pion and kaon PDFs

5 May 2026, 15:10
20m
Sala IMPERIALE A, First Floor (Hotel Carlton)

Sala IMPERIALE A, First Floor

Hotel Carlton

Talk WG1 Structure Functions and Parton Densities WG1 Structure functions and parton densities

Speaker

Dr Wally Melnitchouk (Jefferson Lab)

Description

We review recent results from the JAM Collaboration on pion and kaon PDFs obtained from global QCD analysis of experimental Drell-Yan and leading neutron electroproduction data, together with lattice QCD calculations of PDF moments and Ioffe time distributions. The analysis indicates a softer valence up-quark distribution in the $K^+$ compared with the $\pi^+$, and provides the first empirical evidence for significantly different valence up and anti-strange densities in the kaon. Inclusion of recent lattice calculations of gluonic pseudo Ioffe-time distributions also significantly reduces uncertainties on the gluon PDF, revealing a higher gluon density in the pion at large momentum fractions than in the proton.

Speaker confirmation Yes

Author

Dr Wally Melnitchouk (Jefferson Lab)

Co-authors

Alex NieMiera (Michigan State U.) Chueng Ji (NCSU) Fernanda Steffens (Bonn) Huey-Wen Lin (Michigan State U.) Nobuo Sato (Jefferson Lab) Patrick Barry (ANL) William Good (Michigan State U.)

Presentation materials