Nondiffractive feature of $\gamma N\to {\rho }^{\pm }N$ with $\rho$-meson electromagnetic multipole moments

Abstract

We investigate photoproduction of charged $\rho$ off the nucleon using $\rho (770)+\pi (140)$ Regge pole exchanges by considering the $\rho$-meson electromagnetic multipole moments. The significance of the Ward identity at the $\gamma \rho \rho$ vertex is emphasized for current conservation in the process. Given $\pi$ exchange with the well-known coupling constants for $\gamma \pi \rho$ and $\pi NN$, we analyze the role of the $\rho$ exchange in the $\gamma p\to {\rho }^{+}n$ and $\gamma n\to {\rho }^{-}p$ processes without model-dependences except for the magnetic moment ${\mu }_{{\rho }^{\pm }}=\pm 2.01$ and electric quadrupole moment ${\mathcal{Q}}_{{\rho }^{\pm }}=\pm 0.027$ fm${}^2$ taken from theoretical estimates. The nondiffractive feature of both cross sections is reproduced with a rapid decrease beyond the resonance region by the dominance of $\pi$ exchange over the $\rho$\,. % Cross sections for differential and density matrix elements are presented to compare with existing data. The parity and photon polarization asymmetries are predicted to demonstrate the apparent roles of the $\rho$-meson electromagnetic multipole moments.

5 pages, 8 figures

References in corpus (3)

• Vector meson form factors and their quark-mass dependence
• Unitarity constraints on neutral pion electroproduction
• Scalar-Meson - Baryon Coupling Constants in QCD Sum Rules

Cited by in corpus (5)

• Investigating convergence of the reaction $\gamma p\to {\pi }^{\pm }\Delta$ and tensor meson $a_2$ exchange at high energy
• Regge approach to the reaction of $\gamma N\to K^{\ast }\Lambda$
• Features of forward $\pi N$ scattering from a Reggeized model
• Photoproductions of $f_1(1285)$ and ${\eta }^{\prime }(958)$ from the analysis of CLAS data with the Primakoff effect at high energies
• Reggeized model for $\gamma p\to {\rho }^{-}{\Delta }^{++}(1232)$ photoproduction