Paper Title
Study The Attenuation Coefficient of Granite to Use it as Shields Against Gamma Ray

Abstract
The present work investigated the linear and mass attenuation coefficients of gamma rays practically and theoretically using spectroscopy gamma ray (UCS-20) and by using program (XCOM)) for various types of common use granite, and compare them with the lead because it�s high blocking ability for this type of radiation. This paper concluded through linear and mass attenuation coefficients measurements that these coefficients decrease with increasing incident photons energy. Measurements also showed that the linear attenuation coefficients appropriate linearly with density while mass attenuation coefficients do not get affected. Keywords - gamma rays, attenuation coefficient (linear and mass), building materials, sodium Iodide detector.