Hello everyone. I need a hint of how to do the following question. I spent long time trying to solve and I could not do it. An ionization chamber that will be used to measure fast neutron absorbed dose rate consists of ethylene (C2H4) gas at a density of (1.2×10^-4 g/cm^3) enclosed by polyethylene (C2H4)n walls in a parallel-plate geometry, where the active volume of the chamber is 5 cm^3. The atom density for hydrogen in polyethylene is 8.6×1022 atoms per gram.The chamber will be exposed to a uniform beam of fast neutrons with a fluence rate per unit energy of (10^5 n /cm^2 s MeV) in the energy range of 0.1 to 10 MeV. The dominant reaction in the chamber walls is elastic scatter with hydrogen, and the microscopic cross-section for hydrogen scatter with neutrons in the energy range 0.1 to 10 MeV is approximated by: σ(E)= (4.83/E^0.5)-0.578 where neutron energy E has units of MeV and σ(E) has units of barns. For a given neutron energy E, the average energy for a scattered proton is E / 2. The chamber walls are thick enough to achieve charged particle equilibrium for the scattered protons, and offer negligible attenuation to the incident fast neutrons. The stopping powers for scattered protons in the chamber wall and in the chamber gas are equal. What is the expected absorbed dose rate (in units of MeV/g*s ) to the chamber wall due to the fast neutron irradiation as described above?