ausblenden:
Schlagwörter:
galaxies: clusters: general
galaxies: clusters: intracluster medium
galaxies: evolution
galaxies: star formation
X-rays: galaxies:
clusters
Astrophysics - Astrophysics of Galaxies
Zusammenfassung:
We compile a sample of Sloan Digital Sky Survey (SDSS) galaxy clusters with high-quality Chandra X-ray data to directly study the influence of the dense intracluster medium (ICM) on the quenching of satellite galaxies. We study the quenched fractions of satellite galaxies as a function of ICM density for low- (109 ≲ M ⋆ ≲ 1010 M ☉), intermediate- (1010 ≲ M ⋆ ≲ 1010.5 M ☉), and high-mass (M ⋆ ≳ 1010.5 M ☉) satellite galaxies with >3000 satellite galaxies across 24 low-redshift (z < 0.1) clusters. For low-mass galaxies we find evidence for a broken power-law trend between satellite quenched fraction and local ICM density. The quenched fraction increases modestly at ICM densities below a threshold before increasing sharply beyond this threshold toward the cluster center. We show that this increase in quenched fraction at high ICM density is well matched by a simple, analytic model of ram pressure stripping. These results are consistent with a picture where low-mass cluster galaxies experience an initial, slow-quenching mode driven by steady gas depletion, followed by rapid quenching associated with ram pressure of cold-gas stripping near (one-quarter of the virial radius, on average) the cluster center.
