{"about":{"site":"https://codewithpapers.app","non_affiliation":"Code with Papers and Syntology are not affiliated with, endorsed by, or sponsored by Papers with Code, Meta, or the pwc-archive mirror.","licence":"CC BY-SA 4.0","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","attribution":"https://codewithpapers.app/attribution","modified":"archive material modified by Syntology; see the attribution page"},"url":"/paper/the-r-resonance-with-physical-pion-mass-from","title":"The $ρ$-resonance with physical pion mass from $N_f=2$ lattice QCD","arxiv_id":"2006.13805","date":"2020-06-24","proceeding":null,"authors":["Matthias Fischer","Bartosz Kostrzewa","Maxim Mai","Marcus Petschlies","Ferenc Pittler","Martin Ueding","Carsten Urbach","Markus Werner"],"abstract":"We present the first-ever lattice computation of pi pi-scattering in the I=1 channel with Nf=2 dynamical quark flavours obtained including an ensemble with physical value of the pion mass. Employing a global fit to data at three values of the pion mass, we determine the universal parameters of the rho-resonance. We carefully investigate systematic uncertainties by determining energy eigenvalues using different methods and by comparing inverse amplitude method and Breit-Wigner type parametrizations. Overall, we find mass 786(20) MeV and width 180(6) MeV, including statistical and systematic uncertainties. In stark disagreement with the previous Nf=2 extrapolations from higher than physical pion mass results, our mass value is in good agreement with experiment, while the width is slightly too high.","url_abs":"https://arxiv.org/abs/2006.13805v1","url_pdf":"https://arxiv.org/pdf/2006.13805v1.pdf","source":{"archive":"pwc-archive (Hugging Face), CC BY-SA 4.0","snapshot":"2025-07-28","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","row_kind":"links_only","authors_date_abstract":"arXiv metadata, CC0 1.0 (https://info.arxiv.org/help/license), from the Kaggle arXiv metadata snapshot of 2026-09-12"},"code_links":[{"paper_slug":"the-r-resonance-with-physical-pion-mass-from","repo_url":"https://github.com/urbach/datarhonf2","is_official":1,"mentioned_in_paper":1,"mentioned_in_github":1,"framework":"none","reach":null},{"paper_slug":"the-r-resonance-with-physical-pion-mass-from","repo_url":"https://github.com/HISKP-LQCD/Nf211-2pi-I1-scattering-data","is_official":0,"mentioned_in_paper":0,"mentioned_in_github":1,"framework":"none","reach":null}],"tasks":[],"methods":[],"datasets_introduced":[],"methods_introduced":[],"results":[],"syntology":{"atlas_url":null,"mcp":null,"developers":"https://syntology.ai/developers"},"arxiv_metadata":null,"syntology_extracted_results":null}