Cooperative damping mechanism of the resonance in the nuclear photoabsorption

Abstract

We propose a resonance damping mechanism to explain the disappearance of the peaks around the position of the resonances higher than the $\Delta$ resonance in the nuclear photoabsorption. This phenomenon is understood by taking into account the cooperative effect of the collision broadening of $\Delta$ and $N^{\ast }$, the pion distortion and the interference in the two-pion photoproduction processes in the nuclear medium.

Comments: 11 pages, uses revtex.sty. To appear in Phys. Rev. Lett