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Title: Baryon transition form factors at the pole

Electromagnetic resonance properties are uniquely defined at the pole and do not depend on the separation of the resonance from background or the decay channel. Photon-nucleon branching ratios are nowadays often quoted at the pole, and we generalize the considerations to the case of virtual photons. In this paper, we derive and compare relations for nucleon to baryon transition form factors both for the Breit-Wigner and the pole positions. Using the MAID2007 and SAID SM08 partial wave analyses of pion electroproduction data, we compare the $$G_M$$, $$G_E$$, and $$G_C$$ form factors for the $$\Delta(1232)$$ resonance excitation at the Breit-Wigner resonance and pole positions up to $Q^2=5$ GeV$^2$. We also explore the $E/M$ and $S/M$ ratios as functions of $Q^2$. Finally, for pole and residue extraction, we apply the Laurent + Pietarinen method.
 [1] ;  [2] ;  [3] ;  [4] ;  [4] ;  [4] ;  [4] ;  [5]
  1. Univ. of Mainz (Germany). Inst. of Nuclear Physics
  2. George Washington Univ., Washington, DC (United States); Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
  3. George Washington Univ., Washington, DC (United States)
  4. Univ. of Tuzla (Bosnia and Herzegovina). Faculty of Natural Sciences and Mathematics
  5. Ruder Boskovic Inst., Zagreb (Croatia)
Publication Date:
Report Number(s):
JLAB-THY-16-2315; DOE/OR/23177-3910; arXiv:1606.00371
Journal ID: ISSN 2469-9985
Grant/Contract Number:
SC0014133; AC05-06OR23177; SFB 1044; 13-02-00425; PHY-1452055; 1415459
Accepted Manuscript
Journal Name:
Physical Review C
Additional Journal Information:
Journal Volume: 94; Journal Issue: 6; Journal ID: ISSN 2469-9985
American Physical Society (APS)
Research Org:
George Washington Univ., Washington, DC (United States); Univ. of Mainz (Germany); Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Univ. of Tuzla (Bosnia and Herzegovina)
Sponsoring Org:
USDOE Office of Science (SC), Nuclear Physics (NP) (SC-26); National Science Foundation (NSF); German Research Foundation (DFG); Russian Foundation for Basic Research (RFBR)
Country of Publication:
United States
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; lepton induced nuclear reactions; nuclear reactions; baryons; form factors
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1336971