The XXL survey has mapped two extragalactic regions of 25 deg2, using 10 ks XMM observations down to a point-source sensitivity of ~ 5 10-15 erg/s/cm2 in the [0.5-2] keV band.
It is the largest XMM project approved to date (3Ms in December 2010, >6Ms in total).
As of December 2015, some 450 new galaxy clusters are detected out to z~1.5-2 as well as more than 22,000 active galactic nuclei (AGNs) out to z~4.
The main goal of the project is to constrain the Dark Energy equation of state using clusters of galaxies. This survey will also have lasting legacy value for cluster scaling laws and studies of AGNs and X-ray background.
This project builds on the experience acquired during the ten years XMM-LSS pilot survey. It is open to any scientist belonging to the international astronomical community, and interested in actively contributing to the general legacy effort.
The two surveyed regions are:
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CFHTLS W1 centre: 2h23min -4deg30' (J2000), 25 deg2
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BCS centre: 23h30min -55deg00' (J2000), 25 deg2
Observations were completed in 2013
The XXL exposure ans sensitivity maps are available here
(Download a synthetic overview of the XXL project xxl-overview.pdf)