Effective areas of astronomical X-ray telescopes for CubeSats and rocket experiments

We address the problem of estimating the sensitivity of astronomical X-ray telescopes, with emphasis on the calculation of effective areas for such telescopes designed for rocket experiments and CubeSat flights. This effective area is one of the principal parameters when justifying real space application. Indeed, the larger the effective area is, the more efficient the optical system, able to provide images of fainter and more distant celestial targets. We discuss the estimation of the effective collecting area of an X-ray telescope by two different methods, an analytical method and a simulation algorithm, and then compare the results.