Prospects for observing the Galactic Center: combining LBT LINC-NIRVANA observations in the near-infrared with observations in the mm/sub-mm wavelength domain

Eckart, Andreas; Witzel, Gunther; Kunneriath, Devaky; König, Sabine; Straubmeier, Christian; Bertram, Thomas; Zamaninasab, Mohammad; Schödel, Rainer; Muzic, Koraljka; Tremou, Evangelia; Meyer, Leonhard; Rost, Steffen; Vogel, Stuart; Wiesemeyer, Helmut; Sjouwerman, Lorant; Herbst, Tom
Optical and Infrared Interferometry. Edited by Schöller, Markus; Danchi, William C.; Delplancke, Françoise. Proceedings of the SPIE, Volume 7013, pp. 70134L-70134L-12 (2008).


As a near-infrared (NIR) wide field interferometric imager offering an angular resolution of about 10 milliarcseconds LINC-NIRVANA at the Large Binocular Telescope will be an ideal instrument for imaging the center of the Milky Way especially in conjunction with mm/sub-mm interferometers like CARMA, ATCA or, in the near future, ALMA. Sagittarius A* (Sgr A*) is the electromagnetc manifestation of the ~4×106M super-massive black hole (SMBH) at the Galactic Center. First results from a mult-wavelength campaign focused on Sgr A*, based on the VLT and on CARMA, ATCA, and the IRAM 30m-telescope, in May 2007 show that the NIR data are consistent with partially depolarized non-thermal emission from confined hot spots in relativistic orbits around SgrA*. A 3mm flare following a May 2007 NIR flare is consistent with SSC emission from adiabatically expanding plasma in a wind or jet. With the LBT and ALMA we will be able to study the spectral evolution of NIR/sub-mm/mm flare emission in order to constrain the emission mechanism, the jet/wind physics, and possibly determine the angular momentum of the SMBH. LINC/NIRVANA will also serve to investigate the stellar population and dynamics in the cluster surrounding Sgr A*. A particular emphasis will lie on examining dust embedded and young stars and to unravel the star formation history in the cluster. For the 0.3 parsec core radius central star cluster the investigation of will be investigated.