For the study of the RHICf-II detector longitudinal length, dimension of the tungsten + silicon composition in Norbert's simulation was changed to RHICf-II detector one as 18 cm x 8 cm. Since the first 11 tungsten layers of RHICf detector shows enough performance for photon but latter 5 layers of thicker tungsten doesn't for neutron, number of latter tungsten and its thickness was studied for neutron: 11 layers of 7 mm tungsten + (5, 6, 7, 8, or 9) layers of (14, 21, or 28 mm) tungsten.
