Hi everyone, I have a simple problem for you. If we have an isotropic particle density n(r,E) where r is the radius and E the energy in a sphere of radius R, What would be the particle flux over a single side of a detector of area A inside the sphere? What would it be also if the detector's acceptance would be D? The first aproach i have tried is that the flux should be around n*V/4pi where n is the particle density and v the mean velocity of the particles and 4pi the total solid angle.The flux over one side of the detector should be 1/2 of the total flux as it is isotropic. In the case of the acceptance of the detector, simply multiplying the total flux n*v/4pi by the acceptance would be the flux over the detector´s surface. Thanx and regards.