The Atacama Cosmology Telescope: The Two-season ACTPol Sunyaev–Zel’dovich Effect Selected Cluster Catalog

Journal Article · Thu Mar 08 00:00:00 EST 2018 · The Astrophysical Journal. Supplement Series (Online)

DOI:https://doi.org/10.3847/1538-4365/aaa6cb· OSTI ID:1542032

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; Næss, 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 ; Engelen, Alexander van; Vavagiakis, Eve M.; Wollack, Edward J.

We introduce a catalog of 182 galaxy clusters detected through the Sunyaev–Zel'dovich (SZ) effect by the Atacama Cosmology Telescope in a contiguous 987.5 deg² 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 calculated photometric redshifts for clusters using a pipeline that achieves accuracy Δz/(1 + z) = 0.015 when tested on Sloan Digital Sky Survey data. Under the assumption that clusters can be described by the so-called universal pressure profile (UPP) and its associated mass scaling law, the full signal-to-noise ratio > 4 sample spans the mass range $$1.6\lt {M}_{500{\rm{c}}}^{\mathrm{UPP}}/{10}^{14}\,{M}_{\odot }\lt 9.1$$, with median $${M}_{500{\rm{c}}}^{\mathrm{UPP}}=3.1\times {10}^{14}\,{M}_{\odot }$$. 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 that the ratio of the UPP-based SZ mass to richness-based weak-lensing mass is $$\langle {M}_{500{\rm{c}}}^{\mathrm{UPP}}\rangle /\langle {M}_{500{\rm{c}}}^{\lambda \mathrm{WL}}\rangle =0.68\pm 0.11$$. After applying this calibration, the mass distribution for clusters with M 500c > 4 × 10¹⁴ M_⊙ is consistent with the number of such clusters found in the South Pole Telescope SZ survey.

• Research Organization: Carnegie Mellon Univ., Pittsburgh, PA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Advanced Scientific Computing Research (ASCR)
• Contributing Organization: ACT Collaboration
• Grant/Contract Number: SC0011114
• OSTI ID: 1542032
• Journal Information: The Astrophysical Journal. Supplement Series (Online), Vol. 235, Issue 1; ISSN 1538-4365
• Publisher: American Astronomical Society/IOP
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
cosmology: large-scale structure of universe
cosmology: observations
galaxies: clusters: general