CARMA follow-up of the northern unconfirmed PLANCK galaxy cluster candidates

TL;DR

This study uses CARMA observations to confirm two galaxy clusters from the PLANCK satellite data, refines their locations and mass estimates, and suggests the third candidate is likely a galactic cold-core object, supporting high catalog purity.

Contribution

First detailed follow-up observations of unconfirmed PLANCK galaxy cluster candidates using CARMA, confirming two clusters and refining their properties.

Findings

Confirmed two galaxy clusters with high significance

Refined centroid locations and mass estimates for the clusters

Identified the third candidate as likely a galactic cold-core object

Abstract

We present CARMA observations of the three northern unconfirmed galaxy clusters discovered by the PLANCK satellite. We confirm the existence of two massive clusters (PLCKESZ G115.71+17.52 and PLCKESZ G121.11+57.01) at high significance. For these clusters, we present refined centroid locations from the 31 GHz CARMA data, as well as mass estimates obtained from a joint analysis of CARMA and PLANCK data. We do not detect the third candidate, PLCKESZ G189.84-37.24, and place an upper limit on its mass of M500 < 3.2 X 10^(14) M_SUN at 68% confidence. Considering our data and the characteristics of the PLANCK Early Release SZ Catalog, we conclude that this object is likely to be a cold-core object in the plane of our Galaxy. As a result, we estimate the purity of the ESZ Catalog to be greater than 99.5%.