Strong gravitational lensing at different physical scales
by
Claudio Grillo(DARK)
→
Europe/Stockholm
FA31
FA31
Description
Strong gravitational lensing has become a powerful tool that can be used to address a number of problems in modern cosmology and galaxy evolution. Given the fact that the gravitational deflection of light is determined only by the gravitational field through which light propagates, the gravitational lensing effect is independent of the nature of the matter and of its state. This implies that lensing is able to measure both dark and baryonic (luminous) matter, in equilibrium or far out of it. From the image configuration of a lensing system the total mass of the lens, within a cylinder with a diameter of the average image separation and centred on the lens, can be estimated very accurately. Mass measurements with a precision of a few percent can be achieved by means of detailed lens models in multiple image systems. These are by far the most precise mass determinations in extragalactic astronomy. Strong gravitational lensing has already yielded groundbreaking results detecting low-mass dark-matter sub-haloes without visible stars in a few lens galaxies. Now, thanks also to strong gravitational lensing, the prospects for making a giant step forward in our understanding of the nature of dark matter are very promising. Within this framework, I will show some recent results and future plans in lens galaxies and clusters of galaxies.
