A parallel beam of neutrons with cross section area S=4cm2 and intensity 106 neutrons /cm2/s is incident perpendicularly on a slab of material of thickness L. Assume the only possible interactions in the target are absorption and scattering. The absorption and total microscopic cross sections for the material are t=s=1.5b The atom density for the material is 1.51024 atoms /cm3. - 6.1 [5] Calculate the scattering microscopic cross section for the target material s (for the slab material) - 6.2 [5] Calculate the total mean free path. - 6.3 [5] Calculate the total interaction rate (interactions/s) in the (entire) target for L=0.5cm. 6.4 [5] Redo part 6.3 if the same beam is incident on the same target, but at a 45 angle with the normal. 6.5 [5] The attenuation factor eaa depends strongly on the product between the macroscopic cross section and the length a neutron needs to travel before escaping, a quantity often referred to as the optical thickness (by analogy to light propagation) and expressed as T=aa. 6.6 [1] Find optical thickness for case 6.3 and 6.4