New large-$$N_c$$ relations for the electromagnetic nucleon-to-$$\Delta$$ form factors

Journal Article · Sat Dec 01 00:00:00 EST 2007 · Phys.Rev.D

DOI:https://doi.org/10.1103/PhysRevD.76.111501· OSTI ID:896651

Pascalutsa, Vladimir; Vanderhaeghen, Marc

We establish relations which express the three $$N\to \Delta$$ transition form factors in terms of the nucleon form factors. These relations are based on the known large-$$N_c$$ relation between the $$N\to \De$$ electric quadrupole moment and the neutron charge radius, and a newly derived large-$$N_c$$ relation between the electric quadrupole ($E2$) and Coulomb quadrupole ($C2$) transitions. Namely, in the large-$$N_c$$ limit we find $C2=E2$. We show that these relations provide predictions for the $$N\to\Delta$$ electromagnetic form factors which are found to be in very good agreement with experiment for moderate momentum transfers. They also provide constraints for the $$N \to \Delta$$ GPDs.

• Research Organization: Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
• Sponsoring Organization: USDOE - Office of Energy Research (ER)
• DOE Contract Number: AC05-06OR23177
• OSTI ID: 896651
• Report Number(s): JLAB-THY-06-605; DOE/OR/23177-0014
• Journal Information: Phys.Rev.D, Vol. 76
• Country of Publication: United States
• Language: English