The unmixed kinematics and origins of diffuse stellar light in the core of the Hydra I cluster (Abell 1060)

Abstract

Diffuse intracluster light (ICL) and cD galaxy halos are believed to originate from galaxy evolution and disruption. We present a kinematic study of the ICL in the Hydra I cluster core, using planetary nebulas (PNs) as tracers. We used multi-slit imaging spectroscopy with FORS2 on VLT-UT1 to detect 56 PNs associated with diffuse light in the central 100 x 100 kpc^2 of Hydra I. We measured their [OIII] magnitudes, sky positions, and velocity distribution (LOSVD), and compared with the phase-space distribution of nearby galaxies. The luminosity function of the detected PNs is consistent with that expected at a distance of ~50 Mpc. Their number density is ~4 times lower for the light seen than expected, and we discuss ram pressure stripping of the PNs by the hot ICM as one of the possible explanations. The LOSVD histogram of the PNs is highly non-Gaussian and multipeaked: it is dominated by a broad central component with sigma~500 km/s at around the average velocity of the cluster, and shows two additional narrower peaks at 1800 km/s and 5000 km/s. The main component is broadly consistent with the outward continuation of the intracluster halo of NGC 3311, which was earlier shown to have a velocity dispersion of ~470 km/s at radii of >50". Galaxies with velocities in this range are absent in the central 100 x 100 kpc^2 and may have been disrupted earlier to build this component. The PNs in the second peak in the LOSVD at 5000 km/s are coincident spatially and in velocities with a group of dwarf galaxies in the MSIS field. They may trace the debris from the ongoing tidal disruption of these galaxies. Most of the diffuse light in the core of Hydra is still not phase-mixed. The build-up of ICL and the dynamically hot cD halo around NGC 3311 are ongoing, through the accretion of material from galaxies falling into the cluster core and tidally interacting with its potential well.

12 pages, 7 figures, accepted for publication in A&A

References in corpus (14)

• The Importance of Mergers for the Origin of Intracluster Stars in Cosmological Simulations of Galaxy Clusters
• Kinematic properties of early-type galaxy haloes using planetary nebulae
• The Formation and Evolution of Intracluster Light
• Diffuse Optical Light in Galaxy Clusters II: Correlations with Cluster Properties
• Planetary nebulae as tracers of galaxy stellar populations
• Planetary Nebulae in Face-On Spiral Galaxies. I. Planetary Nebula Photometry and Distances
• The Metallicity Distribution of Intracluster Stars in Virgo
• The early-type dwarf galaxy population of the Hydra I cluster
• The Kinematics of Intracluster Planetary Nebulae and the On-Going Subcluster Merger in the Coma Cluster Core
• Counter-dispersed slitless-spectroscopy technique: planetary nebula velocities in the halo of NGC 1399
• Diffuse stellar emission in X-ray luminous galaxy clusters at z~0.3 I. Is the diffuse optical light boosted and rejuvenated in merging clusters?
• The dynamically hot stellar halo around NGC 3311: a small cluster-dominated central galaxy
• Expansion velocities and core masses of bright planetary nebulae in the Virgo cluster
• Intracluster Planetary Nebulae in the Hydra I cluster

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