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BCGS Seminar 2015

Workshop A1: Supermassive black holes and their host galaxies

Andreas Eckart, Gerold Busch, Nastaran Fazeli, Michal Zajaček




Most galaxies are thought to host a supermassive black hole, having masses from millions to billions of the mass of the sun, in their center.
The first half of the workshop will focus on the supermassive black hole in the center of our Galaxy, the Milky Way. By measuring the orbits of the stars surrounding the center of our Galaxy with highest angular resolution, we can be quite confident that the Galaxy contains a supermassive black hole of mass 4*10^6 Msun in its center. It is associated with the compact radio source Sagittarius A* that shows flare emission from the millimeter to the X-ray domain. Due to its proximity, the Galactic Center is an ideal laboratory to study the vicinity of these extreme objects and to test the laws of physics in the presence of highly compact masses. Several dusty objects are found in the neighborhood of the central black hole. One of them, the dusty object G2/DSO, has been monitored during the last years. Its nature is still unclear: Depending on its nature, its close passage might produce enhanced accretion activity and will allow further conclusions on the nature of the circumnuclear environment.
In the second part of the workshop, we will go out to more distant galaxies: Active galaxies (at higher redshifts also known as Quasars) belong to the most extreme objects in our cosmos. They show point source emission in their centers that can outshine the light of the host galaxy, that contains many billions of stars, by a factor of up to thousand. The emission is thought to come from accretion of mass onto the central supermassive black hole. A crucial point in black hole feeding is that gas has to lose angular momentum. Here, galaxy-galaxy interaction but also internal processes like stellar bars or spiral arms etc. come into play. Furthermore, strong correlations between the mass of the central black hole and the host galaxies show that the central black hole plays an essential role in the evolution of galaxies. We will discuss how observations with state-of-the-art telescopes as the Very Large Telescope in the Chilean desert allow us to analyze the centers of galaxies that are hundreds of millions of lightyears away from us.





Part I: The Galactic Center.

Lecture: Andreas Eckart
Tutorial: Michal Zajaček

Part II: Active Galactic Nuclei and their host galaxies.

Lecture: Gerold Busch
Tutorial: Nastaran Fazeli





Practical Session on Galactic Center (M. Zajaček)

Please download the problem sheet. If you have questions, please contact Michal Zajaček (zajacek_at_ph1.uni-koeln.de).





Lecture on AGN host galaxies (G. Busch)

You can download the slides here. If you have questions, contact Gerold Busch (busch_at_ph1.uni-koeln.de).





Practical Session on AGN host galaxies (N. Fazeli)

For the practical session of our workshop, we will need the FITS files viewer QFitsView. Please download it from Thomas Ott's homepage: http://www.mpe.mpg.de/~ott/QFitsView/.
Under Windows just start the exe-file. Under Linux, make the binary executable (chmod a+x QFitsView_3.1.linux**) and run it with ./QFitsView_3.1.linux** in the folder that you downloaded it to. You might want to move it to a folder that is contained in your path-variable (e.g. /usr/bin/), then you can start it from every directory...

Please also download the following data cubes:
HE1029-1831 FOV: 8x8
HE1029-1831 FOV: 3x3

In case you have any problems with the installation or download, please contact Nastaran Fazeli (fazeli_at_ph1.uni-koeln.de) or Gerold Busch (busch_at_ph1.uni-koeln.de). See you on Friday!










last updated: 17 April 2015