NIKA2: a millimeter camera for cluster cosmology
Résumé
Galaxy clusters constitute a major cosmological probe. However, Planck 2015 results have shown
a weak tension between CMB-derived and cluster-derived cosmological parameters. This tension
might be due to poor knowledge of the cluster mass and observable relationship. As for now,
arcmin resolution Sunyaev-Zeldovich (SZ) observations (e.g. SPT, ACT and Planck) only allowed
detailed studies of the intra cluster medium for low redshift clusters (z < 0:2). For high redshift
clusters ( z > 0:5) high resolution and high sensitivity SZ observations are needed. With both
a wide field of view (6.5 arcmin) and a high angular resolution (17.7 and 11.2 arcsec at 150
and 260 GHz), the NIKA2 camera installed at the IRAM 30-m telescope (Pico Veleta, Spain) is
particularly well adapted for these observations. The NIKA2 SZ observation program will map a
large sample of clusters (50) at redshifts between 0.5 and 0.9. As a pilot study for NIKA2, several
clusters of galaxies have been observed with the pathfinder, NIKA, at the IRAM 30-m telescope
to cover the various configurations and observation conditions expected for NIKA2.
| Origine | Fichiers produits par l'(les) auteur(s) |
|---|
Loading...