M32 Analogs? A Population of Massive Ultra Compact Dwarf and Compact
  Elliptical Galaxies in intermediate redshift CLASH Clusters
  We report the discovery of relatively massive, M32-like ultra compact dwarf
(UCD) and compact elliptical (CE) galaxy candidates in $0.2<z<0.6$ massive
galaxy clusters imaged by the Cluster Lensing And Supernova survey with {\it
Hubble} (CLASH) survey. Examining the nearly unresolved objects in the survey,
we identify a sample of compact objects concentrated around the cluster central
galaxies with colors similar to cluster red sequence galaxies. Their colors and
magnitudes suggest stellar masses around $10^9 \mathrm{M_{\odot}}$. More than
half of these galaxies have half-light radii smaller than 200 pc, falling into
the category of massive UCDs and CEs, with properties similar to M32. The
properties are consistent with a tidal stripping origin, but we cannot rule out
the possibility that they are early-formed compact objects trapped in massive
dark matter halos. The 17 CLASH clusters studied in this work on average
contain 2.7 of these objects in their central 0.3 Mpc and 0.6 in their central
50 kpc. Our study demonstrates the possibility of statistically characterizing
UCDs/CEs with a large set of uniform imaging survey data.
