Study of Zeff for DNA, RNA and retina by numerical methods

The effective atomic number of a biomolecule for photon interaction present in DNA, RNA and retina has been estimated in the energy range 0.001-20 MeV using two different numerical methods. The significant variation of Z(eff) with photon energy is reported. This shows that Z(eff) is not constant with energy for photon interaction in DNA, RNA and retinal.