Meson Structure Functions

Pions and kaons play a vital role in the understanding of hadron structure - the emergence of mass within the strong interaction and the modulating effects of Higgs boson mass generation, both of which are fundamental to understanding the evolution of our Universe. Unique insights can be drawn by focusing on the properties of QCD’s (pseudo-) Nambu-Goldstone modes, i.e. pions and kaons; and diverse phenomenological and theoretical approaches are now being deployed in order to develop a coherent image of these bound states. This demands that tight links be drawn between dynamics in QCD’s gauge sector and pion and kaon light-front wave functions, and from there to observables, such as pion and kaon elastic form factors and distribution amplitudes and functions. Measurements of form factors, distribution amplitudes and functions, spectra, charge radii, etc., are all on the same footing. This Working Group combined in a synergistic effort the subbranches (experiment, phenomenology and theory) of the programme.

Meson SF Group QR

Meetings

Regular Meson SF WG take place on Thursdays at 9:00AM ET

• Next meeting: THURSDAY 26 June 2025 (Updates)
• Next meeting: EICUG Meeting mid-July

EIC Meson SF Meeting Material and Summaries

The teleconferencing service is called "ZoomGov". Please see email notification for zoom link.

Github

Meson structure analysis documentation is available on: Meson Structure Github

Workshops

Pion and Kaon Structure at the EIC

• CFNS Workshop 2024 link
• ECT* Workshop 2021 [link]
• CFNS Workshop 2020 [link]
• PIEIC 2018 [link]
• PIEIC 2017 [link]

EIC Yellow Report Workshops

• 4th Yellow Report Workshop, November 19-21, 2020, UCB – Berkeley, CA [link]
• 3rd Yellow Report Workshop, September 16-18, 2020, CUA, Washington D.C. [link]
• 2nd Yellow Report Workshop, May 20-22, 2020, U. of Pavia, Pavia , Italy [link]
• 1st Yellow Report Workshop, March 19-21, 2020, Temple University, Philadelphia [link]
• MIT Kick-off/planning/organization meeting, December 12-13, 2019 [link]

AMBER Workshops

• PAW2024 link

Conference Presentations

• Presentation at POETIC XI, 24 - 28 February, 2025 at Miami, Florida International University (Link to the slides)
• Presentation at PAW2024 (Physics at AMBER International Workshop), 18 - 20 March, 2024 at Château de Bossey, (Link to the slides)
• Presentation at JLUO 2024 at Jefferson Lab, June 2024 (Link to the slides)
• Presentation on "Pion and Kaon Structure at the EIC" at the EHM Workshop IV Perceiving the Emergence of Hadron Mass through AMBER@CERN, 30 November 2020
• Presentation on "Pion and Kaon Structure at the EIC - White Paper" at the CFNS Workshop on Pion and Kaon structure functions at EIC, 2-5 June 2020
• Richard Trotta's presentation at the CFNS Workshop on Pion and Kaon structure functions at EIC , 2-5 June 2020 [pdf]

Publications and other documents

• EIC Yellow report ("Science Requirements and Detector Concepts for the Electron-Ion Collider: EIC Yellow Report") on Arxiv (2021) [link]
• "Revealing the structure of light pseudoscalar mesons at the electron–ion collider" review article published in Journal of Physics G: J.Phys.G 48 (2021) 7, 075106 link; (Arxiv version: Link)
• "Insights into the Emergence of Mass from Studies of Pion and Kaon Structure" review article published in Progress in Particle and Nuclear Physics (2021) (Arxiv version: Link)
• "Pion and Kaon Structure at the Electron-Ion Collider" published in European Physics Journal: Eur.Phys.J.A 55 (2019) 10, 190 Link; (Arxiv version: Link)
• Link to Overleaf review document [link]

• Meson SF WG Action Items for 2023 [link]
• Meson SF WG Action Items for 2022 [link]
• Meson SF WG Action Items for 2021 [link]

Discussions

• Validity of Factorization link

Useful references

• EIC White Paper (updated 2014 version), Eur. Phys. J. A52 (2016) no.9, 268, [link]
• Leading neutron production in e+ p collisions at HERA, Nucl.Phys.B 637 (2002) 3-56 [link]
• Pion structure function from leading neutron electroproduction and SU(2) flavor asymmetry [link]
• Phenomenological Implications of the Nucleon’s Meson Cloud [link]