DAMAE: DArk MAtter In Ellipticals
The DAMAE project is aimed at measuring the relative content of DM in the haloes of elliptical galaxies of various luminosities using primarly extragalactic planetary nebulae (PNe) as dynamial tracers. PNe stand out in the regions where the faint integrated stellar light is unsuitable for kinematical measurement, while DM is predicted to dominate the mass budget and the partition between luminous mass (stars and gas) and DM is less uncertain. We intend to add to the PNe galaxies other objects studied with the strong gravitational lensing and situated at z~0.2 in order to investigate the dark matter content in "time", that is to a direct reading of the evolution, fully understanding that this is just a first step.
The mass distribution obtained with the dynamical models will be compared with the predictions from the currently accepted cosmological model, the so-called ΛCDM (Cold Dark Matter with the addition of a cosmological constant). This model, which works reasonably well to describe the formation and evolution of the large structures in the Universe (galaxy clusters, groups and filaments), lately has faced many flaws on the galaxy scales, at the extend to make viable a large range of Extended Theories of Gravity (ETG). ETG, though very promising for the cosmological consequences, these theories are still in pioneering phase of observational testing.
We will use PN velocity fields in a dozen of elliptical galaxies together with some other technique as the integral field spectroscopy units, the kinematics of gas and stellar component of polar ring galaxies and lensing to significantly test the two alternative scenarios.
The project is funded by Regione Campania (legge 5, 2007).
