Scientific Potential for Interferometric Observations of the Galactic Center

摘要

Stellar proper motions, radial velocities and accelarations obtained with high angular resolution techniques over the past decade have convincingly proven the presence of a central compact dark mass of 3x10~6 M_☉. This mass is most likely associated with the compact radio source Sagittarius A~* and represents one of the best candidates for a super massive Black Hole. This contribution summarizes some important observational facts and outlines the future possibilities for interferometric observations of the Galactic Center. In the near future interferometric observations of that region with the LBT, VLTI and the Keck Interferometer will be possible. Detailed measurements of the stellar orbits close to the center will allow us to precisely determine the compactness, extent and shape of any extended mass contribution e.g. due to a central stellar cusp. Emphasis will be put on the potential of the NIR LBT interferometric camera LINC. Given the combination of large telescope apertures, adaptive optics, and interfer-ometry it is likely that stars with orbital time scales of the order of one year will be detected. Theses sources, however, will most likely not be on simple Keplerian orbits. The effects of measurable prograde relativistic and retrograde Newtonian periastron shifts will result in rosetta shaped orbits. An increased interferometric point source sensitivity will also allow for an effective search and monitoring of an IR counterpart of SgrA~*.