2024/05/14 by Constantia Alexandrou, Simone Bacchio, Alexandrou, Constantia +21 · 4 citations
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Lattice (hep-lat) #High Energy Physics - Phenomenology (hep-ph) #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions
paper · pdf · doi:10.48550/arxiv.2405.08529
openalex publication_date 2024/05/14 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
We present results on the momentum fraction carried by quarks and gluons in the pion and the kaon. We employ three gauge ensembles generated with 𝑁𝑓 = 2 + 1 + 1 Wilson twisted-mass clover-improved fermions with physical quark masses. We perform, for the first time, a continuum extrapolation directly at the physical pion. We find that the total momentum fraction carried by quarks is ⟨𝑥⟩𝜋 𝑞,𝑅 = 0.575(79) and ⟨𝑥⟩𝐾 𝑞,𝑅 = 0.683(50) and by gluons ⟨𝑥⟩𝜋 𝑔,𝑅 = 0.402(53) and ⟨𝑥⟩𝐾 𝑔,𝑅 = 0.422(67) in the pion and in the kaon, respectively, in the MS scheme and at the renormalization scale of 2 GeV. Having computed both the quark and gluon contributions in the continuum limit, we verify the momentum sum, finding 0.984(89) for the pion and 1.13(11) for the kaon.