Constraints on Sgr A*s accretion geometry and plasma characteristics from the 3Msec Chandra (+ multiwavelength) campaign

          @misc{ pirsa_PIRSA:14110066,
            doi = {10.48660/14110066},
            url = {https://pirsa.org/14110066},
            author = {Markoff, Sera},
            keywords = {Strong Gravity},
            language = {en},
            title = {Constraints on Sgr A*s accretion geometry and plasma characteristics from the 3Msec Chandra  (+ multiwavelength) campaign},
            publisher = {Perimeter Institute},
            year = {2014},
            month = {nov},
            note = {PIRSA:14110066 see, \url{https://pirsa.org}}
          }
          

Abstract

Sgr A* is one of the few black holes whose capture radius is just resolvable with the <0.5” spatial resolution of the Chandra X-ray Observatory. Motivated by this potential we proposed for the deepest ever view of our Galactic center in 2012, via a Chandra-HETGS “X-ray Visionary Project”. Involving over 60 members of the Galactic center community, we obtained ~35 days of observations within a single year, for the first time also using the spectral gratings. This campaign doubled the photon count compared to the 12 years of observations before, and involved simultaneous observations from radio through gamma-ray frequencies. We are still analyzing these data sets, in combination with ongoing monitoring campaigns since, which together provide key constraints for the modeling of Sgr A* and environs necessary for the Event Horizon Telescope. I will present the highlights of this campaign so far, with a focus on results that can alter/define our ideas about the accretion geometry and plasma conditions near the black hole.