Friday, May 22, 2009
Do Mergers of Dark Matter Halos Trigger Quasars?
Quasars are extremely bright objects whose light was emitted when the Universe was much younger than today. Some of these objects shine more than all the stars in their host galaxies, which is why we can see them even though they are found at cosmological distances. It is believed that these extremely luminous events are produced as gas falls into a supermassive black hole at the center of each galaxy. The main question is: how can so much gas be deposited into such a little space where the black hole is located?
The current paradigm is that when two galaxies merge, gas is funneled into the center of the remnant. This gas feeds the black hole, producing extremely bright episodes. Galaxies are known to be surrounded by a 'halo' of dark matter, so knowing how halos merge allows us to understand how quasars are activated. We present a simple model of quasars triggered by mergers of dark matter halos. Our predictions show excellent agreement with observations.
Refreshments at 4:00 PM. Seminar begins at 4:10 PM.
Building 8, Room 241
For further information, please call (909) 869-4014