X Marks The Clumps In A Map Of Dark Matter

In this study, Yale assistant professor of astronomy and physics Priyamvada Natarajan and her colleagues demonstrate that, at least in the mass range of typical galaxies in clusters, there is an excellent agreement between the observations and theoretical predictions of the concordance model.

“We used an innovative technique to pick up the effect of precisely the clumps which might otherwise be obscured by the presence of more massive structures,” said Natarajan. “When we compared our results with theoretical expectations of the concordance model, we found extremely good agreement, suggesting that the model passes the substructure test for the mass range we are sensitive to with this technique.”

“We think the properties of these clumps hold a key to the nature of dark matter — which is presently unknown,” said Natarajan. “The question remains whether these predictions and observations agree for smaller mass clumps that are as yet undetected.”

Co-author on the study, funded by Yale University, is Volker Springel, MPA, Garching, Germany. Other collaborators include. Jean-Paul Kneib, LAM – OAMP, Marseille, France, Ian Smail, University of Durham, U.K., and Richard Ellis of Caltech.

Citation: Astrophysical Journal Letters 617: L13-L16 (December 10, 2004)

Text for this article comes from a Yale press releasse.