Investigating the spatial correlation between different emissions in an extended astrophysical source can provide crucial insights into their physical connection, hence it be key to understand nature of system. The point-to-point analysis surface brightness is a reliable method do such analysis. In this work we present PT-REX, software carry out these studies radio and X-ray emission sources. W...

‎the purpose of this paper is to establish some coupled coincidence point theorems for mappings having a mixed $g$-monotone property in partially ordered metric spaces‎. ‎also‎, ‎we present a result on the existence and uniqueness of coupled common fixed points‎. ‎the results presented in the paper generalize and extend several well-known results in the literature‎.