L. Tiator et al., Analysis of resonance multipoles from polarization observables in eta photoproduction - art. no. 035210, PHYS REV C, 6003(3), 1999, pp. 5210
A combined analysis of new eta photoproduction data for total and different
ial cross sections, target asymmetry, and photon asymmetry is presented. Us
ing a few reasonable assumptions we perform the first model-independent ana
lysis of the E0+, E2-, and M2- era photoproduction multipoles. Making use o
f the well-known A(3/2) helicity amplitude of the D-13(1520) state, we extr
act its branching ratio to the eta N channel, Gamma(eta N)/Gamma = (0.08 +/
- 0.01)%. At higher energies, we show that the photon asymmetry is extremel
y sensitive to small multipoles that are excited by photons in the helicity
3/2 state. The new GRAAL photon asymmetry data at higher energy show a cle
ar signal of the F-15(1680) excitation which permits extracting an F-15(168
0) --> eta N branching ratio of (0.15(-0.10)(+0.35))%. [S0556-2813(99)01809
-9].