The Atacama Cosmology Telescope: The Two-Season ACTPol Sunyaev-Zel'dovich Effect Selected Cluster Catalog

• Main Authors: Hilton, Matt, Hasselfield, Matthew, Sifón, Cristóbal, Battaglia, Nicholas, Aiola, Simone, Bharadwaj, V., Bond, J. Richard, Choi, Steve K., Crichton, Devin, Datta, Rahul, Devlin, Mark J., Dunkley, Joanna, Dünner, Rolando, Gallardo, Patricio A., Gralla, Megan, Hincks, Adam D., Ho, Shuay-Pwu P., Hubmayr, Johannes, Huffenberger, Kevin M., Hughes, John P., Koopman, Brian J., Kosowsky, Arthur, Louis, Thibaut, Madhavacheril, Mathew S., Marriage, Tobias A., Maurin, Loïc, McMahon, Jeff, Miyatake, Hironao, Moodley, Kavilan, Naess, Sigurd, Nati, Federico, Newburgh, Laura, Niemack, Michael D., Oguri, Masamune, Page, Lyman A., Partridge, Bruce, Schmitt, Benjamin L., Sievers, Jon, Spergel, David N., Staggs, Suzanne T., Trac, Hy, van Engelen, Alexander, Vavagiakis, Eve M., Wollack, Edward J.
• Format: Text
• Language: unknown
• Published: arXiv 2017
• Subjects: Cosmology and Nongalactic Astrophysics astro-ph.CO; FOS Physical sciences; South Pole; Lambda; South pole
• Online Access: https://dx.doi.org/10.48550/arxiv.1709.05600; https://arxiv.org/abs/1709.05600

We present a catalog of 182 galaxy clusters detected through the Sunyaev-Zel'dovich effect by the Atacama Cosmology Telescope in a contiguous 987.5 deg$^{2}$ field. The clusters were detected as SZ decrements by applying a matched filter to 148 GHz maps that combine the original ACT equatorial survey with data from the first two observing seasons using the ACTPol receiver. Optical/IR confirmation and redshift measurements come from a combination of large public surveys and our own follow-up observations. Where necessary, we measured photometric redshifts for clusters using a pipeline that achieves accuracy $Δz/(1 + z)=0.015$ when tested on SDSS data. Under the assumption that clusters can be described by the so-called Universal Pressure Profile and its associated mass-scaling law, the full signal-to-noise > 4 sample spans the mass range $1.6 < M^{\rm UPP}_{\rm 500c}/10^{14}{\rm M}_{\odot}<9.1$, with median $M^{\rm UPP}_{\rm 500c}=3.1 \times 10^{14}$ M$_{\odot}$. The sample covers the redshift range $0.1 < z < 1.4$ (median $z = 0.49$) and 28 clusters are new discoveries (median $z = 0.80$). We compare our catalog with other overlapping cluster samples selected using the SZ, optical,and X-ray wavelengths. We find the ratio of the UPP-based SZ mass to richness-based weak-lensing mass is $\langle M^{\rm UPP}_{\rm 500c} \rangle / \langle M^{\rm λWL}_{\rm 500c} \rangle = 0.68 \pm 0.11$. After applying this calibration, the mass distribution for clusters with $M_{\rm 500c} > 4 \times 10^{14}$ M$_{\odot}$ is consistent with the number of such clusters found in the South Pole Telescope SZ survey. : Accepted for publication in ApJS; 38 pages, 31 figures; a .fits table that combines tables A1-A3 is available from https://acru.ukzn.ac.za/~mjh/ACTPol_E-D56Catalog (and will be posted on LAMBDA soon)