One of the longstanding unsolved problem in the nuclear physics is that of the nucleon
resonances N* and Δ*. The lifetime of these intermediate states is very short since they
decay strongly. Their parameters, mass, width, and coupling constants to various decay
modes are not well known. To solve this problem, double polarization experiments are
considered to be a very effective tool. I will present the preliminary result of the helicity
asymmetry “E” for γp → π 0 p channel from the first double polarization experiment at
Jefferson Lab and compare this result with the prediction of theoretical models.