c Societ` a Italiana di Fisica / Springer-Verlag 2008 The 11th Workshop on The Physics of Excited Nucleons, NSTAR 2007, was held at the University of Bonn, Germany,fromSeptember58,2007.ItwasthelatestofaseriesofsuccessfulconferencesattheRensselaerPolytechnic Institute (1988), Florida State University (1994 and 2005), Je?erson Lab (1995 and 2000), INT Seattle (1996), GWU ? Washington (1997), ECT Trento (1998), Mainz (2001), Pittsburgh (2002) and the LPSC Grenoble (2004). A Baryon Resonance Analysis Group (BRAG) meeting immediately before the workshop focused especially on the physical meaning of bare and dressed scattering matrix singularities. A focus workshop on? photoproduction rounded o? the NSTAR 2007. The goal of NSTAR 2007 was to bring together experts on all areas of physics relevant to baryon spectroscopy, both in experiment and theory. Latest results were presented in 30 plenary talks and 34 parallel contributions, the proceedings of which are collected in this volume. The workshop was attended by 123 scientists of 41 universities and laboratories from 16 countries. Exciting new high-precision data were shown from facilities in Asia, the US and Europe, e.g. BES, BNL, COSY, ELSA, GRAAL, JLab, MAMI and LEPS. Large-acceptance detectors provide complete angular distributions in many reaction channels. Particular emphasis is put on the measurement of single and double polarisation observables such that many new polarization measurements can be expected in forthcoming meetings.

Invited Talks.- Excited hadrons on the lattice.- Probing the nucleon structure with CLAS.- Physics at ELSA.- Baryon resonance experiments at COSY.- Analysis of the ?-resonance in a finite volume.- Experiments on magnetic moments of excited baryons.- Recent developments in the constituent quark model including quark-antiquark pairs.- Nucleon structure from lattice QCD.- Quark models.- Polarization in hyperon photo- and electro-production.- Recent BESII results.- N* (1670) observed at LNS, Sendai.- Resonances in hadron-induced reactions.- Analysis of CLAS data on double charged-pion electroproduction.- Resonances in chiral unitary approaches.- Analysis of baryon resonances in the coupled-channel Giessen model.- Excited baryons in large Nc QCD.- Physics at MAMI.- The nature of the ?(1405).- Partial-wave analysis and baryon spectroscopy.- Recent results from the MAID and Dubna-Mainz-Taipei PWA analysis.- Partial wave analysis in the Bonn-Gatchina framework.- Current status of a coupled-channel partial wave analysis using data from CLAS at Jefferson Lab.- Chiral corrections to the Roper mass.- The JLab upgrade Studies of the nucleon with CLAS12.- Perspectives for dynamic polarized solid target experiments.- Hadron physics at the FAIR facility.- Dynamical coupled-channels analysis at EBAC.- Contributed Talks.- Chiral constituent quark model study of the process ?p ? ?p.- Flavor asymmetry of the nucleon sea in an unquenched quark model.- How and when can one identify hadronic molecules in the baryon spectrum.- GDH sum rule and double polarization experiments on the deuteron.- ? photoproduction off the nucleon revisited: Evidence for a narrow N(1688) resonance?.- Dipole and quadrupole polarizabilities of the pion.- Three-body hadronic structure of low-lying 1/2+ ?and ? resonances.- A new nucleon resonance in ? photoproduction.- Baryon resonance analysis with Jülich meson exchange model.- Measurement of the beam asymmetry ? in ? 0 ? production off the proton with the CBELSA/TAPS experiment.- Baryon octupole moments.- Selection rules and quark correlations in the N* resonance spectrum.- Radiative decays of the ?*(1700) and the ?*(1520).- Near threshold production of the pseudoscalar mesons at the COSY-11 facility.- Transfer of polarization in hyperon photoproduction.- Study of ?-production reaction ? ?p ? ?n in the near-threshold region.- Helicity amplitudes of nonstrange baryons in the third and fourth resonance region.- A possible tetraquark state in heavy quarkonium decays.- Dynamics of the near threshold ? meson production in proton-proton interaction.- Linearly polarised photons at ELSA and measurement of the beam asymmetry in ?-photoproduction off the proton.- Baryon resonances and strong decays.- Excitation of the Roper resonance in single- and double-pion production in nucleon-nucleon collisions.- Electroexcitation of the Roper resonance from CLAS data.- Cascade resonance properties from charm baryon decays at BABAR.- Unified description of pion production processes on few-nucleon systems.- Nucleon electroweak form factors in a meson-cloud model.- On the nature of the lowest 1/2? baryon nonet and decuplet.- A Regge-plus-resonance approach to kaon production on the nucleon.- Search for exotics in ?D ? ønp reactions near threshold.- Baryon Regge trajectories in the 1/Nc expansion.- Summaries.- A summary of the NSTAR 2007 Workshop.- The physical meaning of scattering matrix singularities in coupled-channel formalisms.