The PIPER Survey: An Initial Look at the Intracluster Globular Cluster Population in the Perseus Cluster

We outline the goals and first results of the Program for Imaging of the PERseus cluster of galaxies (PIPER) project. The first phase of the program builds on deep Hubble Space Telescope ACS/WFC and WFC3/UVIS B and I images of fields throughout the Perseus cluster. Our PIPER target HST fields include major early-type galaxies including the active central giant NGC 1275, known ultra-diffuse galaxies, and the intracluster medium. The resulting photometry reaches deep enough to resolve and measure the globular cluster (GC) populations in the Perseus member galaxies. Here we present initial results for three pairs of fields that confirm the presence of intracluster GCs (IGCs) as distant as 740 kpc from the Perseus center, or 40% of the virial radius of the cluster. The majority of the IGCs are identifiably blue (metal-poor) but there is a trace of a red (metal-rich) component as well, even at these very remote distances.