@article{1f72bf40b54a4beebb1c57cb7894372b,
title = "First measurement of the polarization observable E in the p→(γ→,π+)n reaction up to 2.25 GeV",
abstract = "First results from the longitudinally polarized frozen-spin target (FROST) program are reported. The double-polarization observable E, for the reaction γ→p→→π+n, has been measured using a circularly polarized tagged-photon beam, with energies from 0.35 to 2.37 GeV. The final-state pions were detected with the CEBAF Large Acceptance Spectrometer in Hall B at the Thomas Jefferson National Accelerator Facility. These polarization data agree fairly well with previous partial-wave analyses at low photon energies. Over much of the covered energy range, however, significant deviations are observed, particularly in the high-energy region where high-. L multipoles contribute. The data have been included in new multipole analyses resulting in updated nucleon resonance parameters. We report updated fits from the Bonn-Gatchina, J{\"u}lich-Bonn, and SAID groups.",
keywords = "Baryon spectroscopy, FROST experiment, Pion photoproduction, Polarization observables",
author = "{CLAS Collaboration} and S. Strauch and Briscoe, {W. J.} and M. D{\"o}ring and E. Klempt and Nikonov, {V. A.} and E. Pasyuk and D. R{\"o}nchen and Sarantsev, {A. V.} and I. Strakovsky and R. Workman and Adhikari, {K. P.} and D. Adikaram and Anderson, {M. D.} and {Anefalos Pereira}, S. and Anisovich, {A. V.} and Badui, {R. A.} and J. Ball and V. Batourine and M. Battaglieri and I. Bedlinskiy and N. Benmouna and Biselli, {A. S.} and J. Brock and Brooks, {W. K.} and Burkert, {V. D.} and T. Cao and C. Carlin and Carman, {D. S.} and A. Celentano and S. Chandavar and G. Charles and L. Colaneri and Cole, {P. L.} and N. Compton and M. Contalbrigo and O. Cortes and V. Crede and N. Dashyan and A. D'Angelo and {De Vita}, R. and {De Sanctis}, E. and A. Deur and C. Djalali and Michael Dugger and R. Dupre and H. Egiyan and {El Alaoui}, A. and {El Fassi}, L. and L. Elouadrhiri and Barry Ritchie",
note = "Funding Information: The authors gratefully acknowledge the work of the Jefferson Lab staff. This work was supported by the U.S. National Science Foundation , the U.S. Department of Energy (DOE), the Chilean Comisi{\'o}n Nacional de Investigaci{\'o}n Cient{\'i}fica y Tecnol{\'o}gica ( CONICYT ), the Deutsche Forschungsgemeinschaft ( SFB/TR16 ), the French Centre National de la Recherche Scientifique and Commissariat {\`a} l'Energie Atomique , the Italian Istituto Nazionale di Fisica Nucleare , JSC (JUROPA) at FZ J{\"u}lich, the National Research Foundation of Korea , the Russian Foundation of Fundamental Research , the Russian Science Foundation (RNF), and the UK Science and Technology Facilities Council (STFC). Jefferson Science Associates, LLC, operates the Thomas Jefferson National Accelerator Facility for the United States Department of Energy under contract DE-AC05-060R23177 . Publisher Copyright: {\textcopyright} 2015 The Authors.",
year = "2015",
month = nov,
day = "12",
doi = "10.1016/j.physletb.2015.08.053",
language = "English (US)",
volume = "750",
pages = "53--58",
journal = "Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics",
issn = "0370-2693",
publisher = "Elsevier",
}