Damghan University Press Iranian Journal of Astronomy and Astrophysics 2322-4924 7 2 2020 10 01 Simulation of a Simple Wolter Telescope of Type I by Geant4 for Some Widely Used Materials 77 83 188 10.22128/ijaa.2020.405.1084 EN Mehdi Abbasian Motlagh Faculty of Physics, Semnan University, Semnan, Iran 0000-0002-4315-5665 Gohar Rastegarzadeh Faculty of Physics ,Semnan University, Semnan, Iran Journal Article 2021 04 20 At the present work, the reflection of X-rays from surfaces composed of silicon, gold, iridium, and nickel is simulated in the range of E ≤ 5 keV energy for the two cases, which includes raw mirror surfaces and a typical Wolter-I optics-based X-ray telescope. We used Geant4 and a proper optical extension to use Geant4 as a general purpose X-ray tracing package. The reflectivity of the materials and the efficiency of the telescope for the materials have been obtained as a function of energy. Except for silicon, the efficiencies are close to each other for the materials. Of course, we generally see a larger value for nickel. Due to the importance of Wolter-I optics in the simulation of the X-ray telescopes and enhancement of the sensitivity of X-ray telescopes by increasing the reflectivity, the results of the present study have particular use in the manufacturing process of an X-ray telescope. https://ijaa.du.ac.ir/article_188_b9cf7d7b2612ff190bf67050577936b8.pdf