15th International Workshop on the Physics of Excited Nucleons

Europe/Madrid
Hotel Ribera de Triana - Sevilla Pl. de Chapina, S/N, 41010 Sevilla
Jorge Segovia (U. Pablo de Olavide, Seville), Feliciano De Soto, José Rodríguez-Quintero, Adnan Bashir, Guillermo D. Megías, Juan A. Caballero
Description

NSTAR 2026

The 15th International Workshop on the Physics of Excited Nucleons will take place in Seville from  September 7th to 11th, 2026.

Nucleon excitations are providing a unique opportunity to explore many facets of the non-perturbative strong interaction and how various baryons, including those with strange and heavy flavor content, emerge from Quantum Chromodynamics (QCD), the Poincaré invariant quantum non-Abelian gauge field theory that describes the strong-interaction part of the Standard Model of Particle Physics. The rapid growth of high-quality experimental results on exclusive meson photoproduction off nucleons from CLAS, ELSA, GRAAL, LEPS, and MAMI allow us to pin down reaction amplitudes with unprecedented precision and to establish the baryon spectrum with minimal model dependence. Experiments with hadronic beams (GSI, JPARC) and hadron production in e+e- collisions (BES) extend and complement the scope of baryon spectroscopy, where the importance of baryon states in the evolution of the Universe has also just recently been elucidated.

Space-like resonance electrocouplings can be extracted, based mainly on the CLAS data on exclusive meson electroproduction off nucleons, over a wide range of photon virtualities and provide valuable information on the excited nucleon structure by offering access to non-perturbative strong interaction mechanisms behind the N* generation. The insight into the baryon structure is complemented by the studies of time-like form factors (BABAR, BES, GSI, PANDA).

From the theory side, Dyson-Schwinger-Equations and Lattice-QCD functional approaches are remarkably progressing in describing the baryon spectrum and structure from the first principles of QCD. New opportunities to explore the full spectrum of excited nucleons, strange and heavy baryons as well as exotic multiquark structures in the baryon sector have been offered by advances in QCD-inspired quark models. In addition, effective field theories, such as chiral perturbation theory, provide valuable low-energy benchmarks and constraints that complement first-principle methods. Light-front holography and AdS/QCD models have opened alternative pathways to connect hadron spectroscopy with underlying QCD dynamics, while QCD sum rules continue to serve as a bridge between non-perturbative QCD and phenomenology. Moreover, coupled-channel dynamical models contribute providing essential insights into hadron scattering and decay properties. Taken together, this broad theoretical toolkit offers a comprehensive framework to deepen our understanding of baryon structure and spectrum.

Synergistic efforts between experimentalists and theorists have already demonstrated our capability to address some open key problems of hadron physics on the nature of hadron mass, quark-gluon confinement, dynamical chiral symmetry breaking, and their emergence from QCD. The purpose of this workshop is to share the latest results on various aspects of low-energy QCD dynamics in terms of nucleon excitations and baryon resonances, and to discuss the future developments.

Topics covered in the workshop are:

  • Baryon spectrum through meson photoproduction.
  • Baryon resonances in experiments with hadron beams and in the e+e- collisions.
  • Baryon resonances in ion collisions and their role in cosmology.
  • Baryon structure through meson electroproduction, transition form factors, and time-like form factors.
  • Amplitude analyses and baryon parameter extraction.
  • Baryon spectrum and structure from first principles of QCD.
  • Advances in the modeling of baryon spectrum and structure.
  • Facilities and future projects.
  • Other topics related to N* physics.
Registration
NSTAR 2026 registration
Participants
    • 8:45 AM 9:00 AM
      Opening/closing session
    • 9:00 AM 11:00 AM
      Plenary session
      • 9:00 AM
        The N* electroexcitation and strong QCD from the data of experiments in Hall B at Jlab 30m
        Speaker: Victor Mokeev (Thomas Jefferson National Accelerator Facility)
      • 9:30 AM
        Experimental results on strange baryon spectroscopy and structure 30m
        Speaker: Daniel Carman (Jefferson Laboratory)
      • 10:00 AM
        ANL-Osaka Model for extracting nucleon resonances: past, present and future 30m
        Speaker: Dr Toru Sato
      • 10:30 AM
        Insights into N* resonances using Continuum Schwinger Function Methods 30m
        Speaker: Prof. Craig Roberts
    • 11:00 AM 11:30 AM
      Coffee break 30m
    • 11:30 AM 1:00 PM
      Plenary session
      • 11:30 AM
        Studies of N* and Delta* in pi N --> pi pi N reactions at J-PARC 30m
        Speaker: Dr Hiroyuki Sako (Japan Atomic Energy Agency)
      • 12:00 PM
        Low-lying baryon resonances from Lattice QCD 30m
        Speaker: Colin Morningstar (Carnegie Mellon University)
      • 12:30 PM
        Nucleon Excited States from Lattice QCD and Hamiltonian Effective Field Theory 30m
        Speaker: Jia-jun Wu
    • 1:00 PM 3:00 PM
      Lunch time 2h
    • 3:00 PM 5:00 PM
      Parallel session A
      • 3:00 PM
        Baryon properties using functional methods 30m
        Speaker: Dr Zhao Qian Yao
    • 3:00 PM 5:00 PM
      Parallel session B
      • 3:00 PM
        Coupled channel dynamics for hadron resonances using Effective Field Theory Models 30m
        Speaker: Eulogio Oset
    • 3:00 PM 5:00 PM
      Parallel session C
      • 3:00 PM
        Electroexcitation of Nucleon Resonances with CLAS and Beyond 30m
        Speaker: Ralf Gothe
    • 5:00 PM 5:30 PM
      Coffee break 30m
    • 5:30 PM 7:30 PM
      Parallel session A
      • 5:30 PM
        Hadron charges and sizes 30m
        Speaker: Daniele Binosi
    • 5:30 PM 7:30 PM
      Parallel session B
      • 5:30 PM
        JPAC analyses of hadron spectroscopy 30m
        Speaker: Alessandro Pilloni (University of Messina & INFN Catania)
    • 5:30 PM 7:30 PM
      Parallel session C
      • 5:30 PM
        Multi-dimensional Analyses of Partonic distributions 30m
        Speaker: Andrea Signori (University of Turin and INFN)
    • 9:00 AM 11:00 AM
      Plenary session
      • 9:00 AM
        Baryons at BESIII and Belle II experiments 30m
        Speaker: Karin Schönning
      • 9:30 AM
        Present and future of Baryons with the CBELSA/TAPS experiment at ELSA 30m
        Speaker: Dr Reinhard Beck
      • 10:00 AM
        A review on baryon spectroscopy from a quark model framework 30m
        Speaker: Jean-Marc Richard (University of Lyon & CNRS-IN2P3, France)
      • 10:30 AM
        Towards a theory of hadron resonances 30m
        Speaker: Dr Maxim Mai (University of Bern)
    • 11:00 AM 11:30 AM
      Coffee break 30m
    • 11:30 AM 1:00 PM
      Plenary session
      • 11:30 AM
        The GlueX baryon (and meson) program 30m
        Speaker: Peter Hurck (University of Bonn)
      • 12:00 PM
        Light pentaquark searches with hadron beams (Belle) 30m
        Speaker: Jung-Keun Ahn
      • 12:30 PM
        Exotic hadrons: Review and perspective 30m
        Speaker: Qian Wang (South China Normal University, Guangzhou, China)
    • 1:00 PM 3:00 PM
      Lunch time 2h
    • 3:00 PM 5:00 PM
      Parallel session A
      • 3:00 PM
        Emergence of mass in the gauge sector of QCD 30m
        Speaker: Joannis Papavassiliou
    • 3:00 PM 5:00 PM
      Parallel session B
      • 3:00 PM
        Femtoscopy approach to hadron analysis 30m
        Speaker: Juan M Nieves
    • 3:00 PM 5:00 PM
      Parallel session C
      • 3:00 PM
        GPD and TDA measurements based on hard exclusive pion electroproduction with CLAS at JLAB 30m
        Speaker: Kyungseon Joo (University of Connecticut)
    • 5:00 PM 5:30 PM
      Coffee break 30m
    • 5:30 PM 7:30 PM
      Parallel session A
      • 5:30 PM
        Quark model review of baryon dynamics 30m
        Speaker: Elena Santopinto (INFN)
    • 5:30 PM 7:30 PM
      Parallel session B
      • 5:30 PM
        Dynamical coupled-channel models for hadron dynamics 30m
        Speaker: Michael Doering (The George Washington University)
    • 5:30 PM 7:30 PM
      Parallel session C
      • 5:30 PM
        Transverse Momentum Moments 30m
        Speaker: Alexey Vladimirov (Universidad Complutense de Madrid)
    • 9:00 AM 11:00 AM
      Parallel session A
      • 9:00 AM
        Continuum Schwinger Method analysis of few body problems 30m
        Speaker: Gernot Eichmann
    • 9:00 AM 11:00 AM
      Parallel session B
      • 9:00 AM
        Exotic Hadron Spectroscopy with CLAS/CLAS12 at Jefferson Lab 30m
        Speaker: Prof. Annalisa D'Angelo (University of Roma Tor Vergata & INFN Roma Tor Vergata)
    • 9:00 AM 11:00 AM
      Parallel session C
      • 9:00 AM
        Neutrino Scattering: Connections Across Theory and Experiment 30m
        Speaker: Raul Gonzalez Jimenez (Universidad de Sevilla)
    • 11:00 AM 11:30 AM
      Coffee break 30m
    • 11:30 AM 1:00 PM
      Early (academic) career event
    • 9:00 AM 11:00 AM
      Plenary session
      • 9:00 AM
        Electron Ion Collider Science and project status 30m
        Speaker: Prof. Tanja Horn (Catholic University of America)
      • 9:30 AM
        Experiment – Exploring baryon resonances with transition generalized parton distributions: status and perspectives 30m
        Speaker: Dr Stefan Diehl (Justus Liebig University Giessen and University of Connecticut)
      • 10:00 AM
        Theory – Exploring baryon resonances with transition generalized parton distributions: status and perspectives 30m
        Speaker: Prof. Marc Vaderhaeghen
      • 10:30 AM
        Review on NNPDF Collaboration results 30m
        Speaker: Dr Juan M. Cruz Martinez (Universidad de Sevilla)
    • 11:00 AM 11:30 AM
      Coffee break 30m
    • 11:30 AM 1:00 PM
      Plenary session
      • 11:30 AM
        The COMPASS/AMBER experiment 30m
        Speaker: Dr Oleg Denisov (INFN, sezione di Torino)
      • 12:00 PM
        Gravitational form factors of pions, kaons and nucleons from dispersion relations 30m
        Speaker: Prof. Feng Kun Guo
      • 12:30 PM
        Lattice insights into photo- and electro-production of baryon resonances 30m
        Speaker: Dr Sergey Syritsin
    • 1:00 PM 3:00 PM
      Coffee break: Lunch time
    • 3:00 PM 5:00 PM
      Parallel session A
      • 3:00 PM
        Coupled channel dynamics for baryon resonances from Lattice QCD 30m
        Speaker: John Bulava
    • 3:00 PM 5:00 PM
      Parallel session B
      • 3:00 PM
        Hadron spectroscopy and structure from Light Front Quantization 30m
        Speaker: Chandan Mondal
    • 3:00 PM 5:00 PM
      Parallel session C
      • 3:00 PM
        New Facilities, MESA 30m
        Speaker: Achim Gerold Denig (JGU Mainz)
    • 5:00 PM 5:30 PM
      Coffee break 30m
    • 5:30 PM 7:30 PM
      Parallel session A
      • 5:30 PM
        Baryon structure from lattice QCD 30m
        Speaker: Sara Collins
    • 5:30 PM 7:30 PM
      Parallel session B
      • 5:30 PM
        Generalized Parton Distributions 30m
        Speaker: Cédric Mezrag
    • 5:30 PM 7:30 PM
      Parallel session C
      • 5:30 PM
        Effective Field Theories for Neutron Stars Physics 30m
        Speaker: Jose Manuel Alarcón (Universidad de Alcalá)
    • 9:00 AM 11:00 AM
      Plenary session
      • 9:00 AM
        Future Colliders: Possibilities and challenges 30m
        Speaker: Jacqueline Keintzel (CERN)
      • 9:30 AM
        Hadron physics opportunities at FAIR 30m
        Speaker: Frank Nerling (GSI Darmstadt & GU Frankfurt)
      • 10:00 AM
        Quantum simulations of hadron dynamics 30m
        Speaker: Marc Illa (PNNL)
      • 10:30 AM
        Solving the quantum many-body problem using neural network quantum states 30m
        Speaker: Noemi Rocco (IFIC - Universitat de Valencia)
    • 11:00 AM 11:30 AM
      Coffee break 30m
    • 11:30 AM 1:00 PM
      Plenary session
      • 11:30 AM
        Criticality in Nature’s Strongest Force and the experiments worldwide to measure it such as R​HIC 30m
        Speaker: Prof. Jacquelyn Noronha-Hostler (University of Illinois Urbana Champaign)
      • 12:00 PM
        Search for photoproduction of axionlike particles at GlueX 30m
        Speaker: William King Brooks Jr (Federico Santa Maria Technical University (CL))
      • 12:30 PM
        The Delta excitation and the role it plays for low-energy nuclear interactions, covering both parity conserving 30m
        Speaker: Evgeny Epelbaum (Ruhr-University Bochum)
    • 1:00 PM 1:15 PM
      Opening/closing session