Near infrared polarimetry [Elektronische Ressource] : a tool for testing properties of Sagittarius A_1hn* / vorgelegt von Mohammad Zamaninasab

Near Infrared PolarimetryA Tool for Testing Properties of Sagittarius A*INAUGURAL-DISSERTATIONzurErlangung des Doktorgradesder Mathematisch-Naturwissenschaftlichen Fakultätder Universität zu Kölnvorgelegt vonMohammad Zamaninasabaus TorbateJam, IranKöln 2010Berichterstatter: Prof. Dr. Andreas EckartProf. Dr. J. Anton ZensusTag der letzten mündlichen Prüfung: 19 April 2010The constellation Sagittarius (Credit: Abdul Rahman Sufi (903 AD -986 AD). Kitabsu-war al-kawakib (Book on the Constellations of Fixed Stars, 964)).1AbstractIn this thesis I focus on the results of the data modelings and simulations of near-infrared (NIR) observations of the Sagittarius A* (Sgr A*) counterpart associated withthe super-massive black hole at the Galactic Center (GC).My goal is to investigate and understand the physical processes behind the variabi-lity associated with the NIR flaring emission from Sgr A*. The NIR observations havebeen carried out using the NACO adaptive optics (AO) instrument at the EuropeanSouthern Observatory’s (ESO’s) Very Large Telescope (VLT) and the CIAO NIR came-ra on the Subaru telescope (13 June 2004, 30 July 2005, 1 June 2006, 15 May 2007, 17May 2007 and 28 May 2008). I used a model of synchrotron emission from relativisticelectrons in the inner parts of an accretion disk. The relativistic simulations have beencarried out using the Karas-Yaqoob (KY) ray-tracing code.