20–23 mai 2025
IPGP
Fuseau horaire Europe/Paris

Validation of the Euclid Catalogue of Galaxy Clusters with external data

21 mai 2025, 11:45
15m
IPGP

IPGP

1 rue Jussieu 75005 Paris

Orateur

Anaïs Widmer

Description

The Euclid spacecraft was launched in July 2023 to the Earth-Sun Lagrange point L2. The mission will produce one of the largest galaxy cluster catalogues withtens of thousands of clusters over the 15 000 square degrees of its extragalactic sky survey. This catalogue will need to be validated with external data, in order to check for newly discovered clusters, to prepare analyses of cluster multi-wavelength scaling relations, and to characterize the Euclid selection function. In preparation, we used the Dark Energy Survey (DES) Y1 RedMaPPer catalogue as surrogate for the Euclid catalogue to put in place our validation procedures with different millimeter, optical, and X-ray surveys . We used two complementary matching methods to find counterparts for clusters in position, but also in redshift. These methods will be explained with the example of crossmatches between RedMaPPer and the SRG eROSITA catalogue, which contains a large sample of X-ray clusters in the western Galactic hemisphere.

Speaker information PhD 2nd year

Author

Anaïs Widmer

Documents de présentation