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The Roper Resonance: Still Controversial 60 Years Later
Anthony W Thomas
Few baryon resonances have generated as much discussion, even controversy, as the first positive parity excited state with nucleon quantum numbers. We re-examine the issue using in…
Pion photoproduction of nucleon excited states with Hamiltonian effective field theory
Yu Zhuge, Dan Guo, Zhan-Wei Liu +2
Over the past few years, Hamiltonian effective field theory has been successfully applied to studies of nucleon and hyperon excited states. By discretizing the Hamiltonian in a fin…
Nucleon resonance structure to 2 GeV and the nature of the Roper
Shiryo Owa, Derek B. Leinweber, Anthony W. Thomas
The study of the spectrum of excited states of the nucleon is vital to our understanding of how QCD is realized in the baryon spectrum. Using a simultaneous analysis of the pion nu…
Challenges in the extraction of physics beyond the Standard Model from electron scattering
X. G. Wang, A. W. Thomas
Precise measurements of electron and positron scattering, including parity violation, offer great promise in the search for physics beyond the Standard Model. In this context it is…
Pion photoproduction of nucleon excited states with Hamiltonian effective field theory
Yu Zhuge, Zhan-Wei Liu, Derek B. Leinweber +1
We refine our previous calculation of multipole amplitude for pion photoproduction process, . The treatment of final-state interactions is based upon an…