2024/11/15 by E. Ruiz Arriola, Arriola, Enrique Ruiz, Wojciech Broniówski +1 · 1 citation
Physics and Astronomy · #Black Holes and Theoretical Physics #FOS: Physical sciences #High Energy Physics - Lattice (hep-lat) #High Energy Physics - Phenomenology (hep-ph) #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions
paper · pdf · doi:10.48550/arxiv.2411.10354
openalex publication_date 2024/11/15 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
We analyze the recent MIT lattice data for the gravitational form factors (GFFs) of the pion which extend up to Q2= 2~\rm GeV2 for mπ=170~MeV~\citeHackett:2023nkr. We show that simple monopole fits comply with the old idea of meson dominance. We use Chiral Perturbation theory (χPT) to next-to-leading order (NLO) to transform the MIT data to the physical world with mπ=140~MeV and find that the spin-0 GFF is effectively saturated with the f0(600) and the spin-2 with the f2(1270), with monopole masses mσ= 630(60)~MeV and mf2= 1270(40)~MeV. We determine in passing the chiral low energy constants (LECs) from the MIT lattice data alone 103 ⋅ L11 (mρ2)=1.06(15) , 103 ⋅ L12 (mρ2)= -2.2(1) , 103 ⋅ L13 (mρ2) = -0.7(1.1). which agree in sign and order of magnitude % to be compared with the original estimates by Donoghue and Leutwyler. The corresponding D-term (druck) has the value D(0) = -0.95(3) . We also analyze the sum rules based on perturbative QCD (pQCD) that imply that the corresponding spectral functions are not positive definite. We show that these sum rules are strongly violated in a variety of ππ-K K coupled channel Omnès-Muskhelishvili calculations. This is not mended by the inclusion of the pQCD tail, suggesting the need for an extra negative spectral strength. Using a simple model implementing all sum rules, we find the expected onset of pQCD at very high momenta.