Poster Title: Measuring mass and angular momentum of black holes with high-frequency QPOs
Abstract: So far three galactic microquasars with high-frequency QPOs have been found each of which shows two frequencies which come in a 3:2 ratio. I have deloped a model which uses the Kepler frequency and both of the two epicyclic frequencies of a test particle orbiting a Kerr black hole to explain this ratio. The equations describing the model have exactly one solution, uniquely fixing the angular momentum of the black hole, which it has to have to start the oscillations, and the orbit radius where the oscillations are excited. I found exactly the same values for the angular momentum and the orbit radius by a detailed analysis of the Boyer-Lindquist functions which demonstrates that this angular momentum and this particular orbit radius are special, also from a physics point of view. The model is used to predict the mass of the three microquasars and the Sgr A* black hole using the QPO frequencies measured. The agreement between the predicted mass and the dynamically determined mass is very good for each of the four objects.
Link to poster: N/A