Résumé
We describe a simple locally CAT(0) classifying space for extra extra large
type Artin groups (with all labels at least 5). Furthermore, when the Artin
group is not dihedral, we describe a rank 1 periodic geodesic, thus proving
that extra large type Artin groups are acylindrically hyperbolic. Together with
Property RD proved by Ciabonu, Holt and Rees, the CAT(0) property implies the
Baum-Connes conjecture for all XXL type Artin groups.