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Title: Evidence for Δ(2200)7/2 $-$ from photoproduction and consequence for chiral-symmetry restoration at high mass

We report a partial-wave analysis of new data on the double-polarization variable E for the reactions γp→π +n and γp→π 0p and of further data published earlier. The analysis within the Bonn–Gatchina (BnGa) formalism reveals evidence for a poorly known baryon resonance, the one-star Δ(2200)7/2 $-$. This is the lowest-mass Δ* resonance with spin-parity J P=7/2 $-$. Its mass is significantly higher than the mass of its parity partner Δ(1950)7/2 + which is the lowest-mass Δ* resonance with spin-parity J P=7/2 +. It has been suggested that chiral symmetry might be restored in the high-mass region of hadron excitations, and that these two resonances should be degenerate in mass. Lastly, our findings are in conflict with this prediction.
Authors:
 [1] ; ORCiD logo [2] ;  [3] ; ORCiD logo [3] ; ORCiD logo [1] ; ORCiD logo [2] ;  [1] ;  [4] ;  [3]
  1. Univ. of Bonn (Germany). Helmholtz Inst. for Radiation and Nuclear Physics; Petersburg Nuclear Physics Inst., Gatchina (Russia). Kurchatov Inst.
  2. Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
  3. Univ. of Bonn (Germany). Helmholtz Inst. for Radiation and Nuclear Physics
  4. Univ. of South Carolina, Columbia, SC (United States). Dept. of Physics and Astronomy
Publication Date:
Report Number(s):
JLAB-PHY-17-2404; DOE/OR/23177-4069
Journal ID: ISSN 0370-2693; PII: S0370269316307523; TRN: US1701158
Grant/Contract Number:
AC05-06OR23177
Type:
Accepted Manuscript
Journal Name:
Physics Letters. Section B
Additional Journal Information:
Journal Volume: 766; Journal Issue: C; Journal ID: ISSN 0370-2693
Publisher:
Elsevier
Research Org:
Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)
Sponsoring Org:
USDOE Office of Science (SC), Nuclear Physics (NP) (SC-26)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
OSTI Identifier:
1345563