DM1 - Interacting Dark Matter |
|
Speaker |
Harvey, David |
|
Coauthors |
|
| Talk Title |
The non-gravitational interactions of dark matter in colliding clusters and galaxies. |
|
Abstract |
Despite the successes of the cold dark matter paradigm inconsistencies exist between theory and observations, predicting many more satellite galaxies that should form stars and much higher central densities in galaxy clusters. One method to resolve these inconsistencies is to invoke a self-coupling in the dark sector such that dark matter is in fact collisional. The first constraints on the self-interaction cross-section of dark matter were derived using the Bullet Cluster. In this talk I present the first ever study of a sample of 30 merging galaxy clusters to place constraints on the interaction cross-section of dark matter that does not rely on a single system. Using state-of-the-art data from the Hubble ACS camera and the Chandra Xray observatory I measure the centroids of dark matter, X-ray emitting gas and galaxies. Using an innovative method to interpret mass offsets in merging galaxy clusters I gather unequivocal evidence for the existence of a dark mass and place the strongest constraints on the self-interaction cross-section to date. I will finish by presenting our recent results concerning the curious case of A3827. In this collision of four very large elliptical galaxies I will present the first evidence for interacting dark matter and discuss the potential implications for what dark matter could be. |
|
Talk view |
|
|
|
|