Résumé:

The era of X-ray astronomy issued a new understanding of astrophysical processes by observing the high-energy universe. Focusing X-ray telescopes in particular allowed an unprecedented view into previously obscured or undetected objects. I will first detail my experience constructing and caliating the Wolter Type-I optics for the NuSTAR telescope, which was launched in 2012. I will also discuss how we can use current focusing X-ray observatories, along with complementary multi-wavelength data, to probe the crowded Galactic Center region. In particular, I will focus on the analysis of Sgr A*- the supermassive GC black hole- as well as several recently-discovered X-ray transients.