SIMBAD references

2017ApJ...851...27M - Astrophys. J., 851, 27-27 (2017/December-2)

Evidence of absence of tidal features in the outskirts of ultra diffuse galaxies in the Coma cluster.


Abstract (from CDS):

We study the presence of tidal features associated with ultra diffuse galaxies (UDGs) in galaxy clusters. Specifically, we stack deep Subaru images of UDGs in the Coma cluster to determine whether they show position angle twists at large radii. Selecting galaxies with central surface brightness µ(g,0) 24 magarcsec–2 and projected half-light radius re 1.5 kpc, we identify 287 UDGs in the Yagi et al. catalog of low surface brightness Coma objects. The UDGs have apparent spheroidal shapes with median Sersic index <n>=0.8 and median axis ratio <b/a>=0.7. The images are processed by masking all background objects and rotating to align the major axis before stacking them in bins of properties such as axis ratio, angle of major axis with respect to the cluster center, and separation from cluster center. Our image stacks reach further than 7 kpc (>=4re). Analysis of the isophotes of the stacks reveals that the ellipticity remains constant up to the last measured point, which means that the individual galaxies have a non-varying position angle and axis ratio and show no evidence for tidal disruption out to ∼4re. We demonstrate this explicitly by comparing our stacks with stacks of model UDGs with and without tidal features in their outskirts. We infer that the average tidal radius of the Coma UDGs is >7 kpc and estimate that the average dark matter fraction within the tidal radius of the UDGs inhabiting the innermost 0.5 Mpc of Coma is >99%.

Abstract Copyright: © 2017. The American Astronomical Society. All rights reserved.

Journal keyword(s): galaxies: clusters: individual: Coma - galaxies: photometry - galaxies: structure - galaxies: structure

Simbad objects: 3

goto Full paper

goto View the reference in ADS

To bookmark this query, right click on this link: simbad:2017ApJ...851...27M and select 'bookmark this link' or equivalent in the popup menu


© Université de Strasbourg/CNRS

    • Contact