Exit Doorway State inC12(O16,Be8)Ne20

Abstract
We remark that resonances in the C12(O16, Be8)Ne20 reaction are due to the "exit doorway state," that is ready for decay to the exit channel. We find a parameter-free formula that relates the resonance energy and angular momentum of the C12 + O16 system to those of the C12 + C12 system. If we use the experimental resonance energies of C12 + C12, this formula yields more than a dozen one-to-one correspondences to the resonance energies of C12(O16, Be8)Ne20. We also find a parameter-free formula for C12(O16, He4)Mg24.