Optical validation and characterization of \Planck\ PSZ2 sources at the Canary Islands observatories. I. First year of LP15 observations

Abstract

Using telescopes at the Canary Island observatories, we conducted the long-term observational programme 128-MULTIPLE-16/15B (LP15), a large and complete optical follow-up campaign of all the unidentified PSZ2 sources in the northern sky (Dec>-15 deg) and no correspondence in the first Planck catalogue PSZ1. We perform this optical validation of SZ clusters in order to contribute to the characterization of the actual purity and completeness of full Our validation procedure combines this optical information with SZ emission as traced by the publicly available Planck Compton y-maps. The clusters counterparts are classified according to redshift, velocity dispersion and richness of the clusters. This paper presents the detailed study of 106 objects out of the LP15 sample, corresponding to all the observations carried out during the first year of the programme. We confirmed the optical counterpart for 41 new PSZ2 sources, being 31 of them validated using also velocity dispersion based on our spectroscopic information. This is the largest dataset of newly confirmed PSZ2 sources without any previous optical information. All the confirmed counterparts are rich structures (i.e. they show high velocity dispersion), and are well aligned with the nominal Planck coordinates (~70% of them are located at less than 3 arcmin distance). In total, 65 SZ sources are classified as unconfirmed, being 57 of them due to the absence of an optical over-density, and 8 of them due to a weak association with the observed SZ decrement. Most of the sources with no optical counterpart are located at low galactic latitudes and present strong galactic cirrus in the optical images, being the dust contamination the most probable explanation for their inclusion in the PSZ2 catalogue.

arXiv comment14 pages, 10 figures, 3 tables

References in corpus (30)

• Planck 2015 results. XIII. Cosmological parameters
• HEALPix -- a Framework for High Resolution Discretization, and Fast Analysis of Data Distributed on the Sphere
• The USNO-B Catalog
• K-corrections and filter transformations in the ultraviolet, optical, and near infrared
• The Eighth Data Release of the Sloan Digital Sky Survey: First Data from SDSS-III
• The Galaxy Luminosity Function and Luminosity Density at Redshift z=0.1
• Chandra Cluster Cosmology Project III: Cosmological Parameter Constraints
• A New Method For Galaxy Cluster Detection I: The Algorithm
• Planck 2013 results. XX. Cosmology from Sunyaev-Zeldovich cluster counts
• The MCXC: a Meta-Catalogue of X-ray detected Clusters of galaxies
• Planck 2013 results. XXIX. Planck catalogue of Sunyaev-Zeldovich sources
• Planck Early Results VIII: The all-sky Early Sunyaev-Zeldovich cluster sample
• A catalog of 132,684 clusters of galaxies identified from Sloan Digital Sky Survey III
• A GMBCG Galaxy Cluster Catalog of 55,424 Rich Clusters from SDSS DR7
• The relation between velocity dispersion and mass in simulated clusters of galaxies: dependence on the tracer and the baryonic physics
• Flux- and volume-limited groups/clusters for the SDSS galaxies: catalogues and mass estimation
• Planck 2013 results. XXIX. The Planck catalogue of Sunyaev-Zeldovich sources: Addendum
• Planck intermediate results. XXVI. Optical identification and redshifts of Planck clusters with the RTT150 telescope
• Planck Intermediate Results. XXXVI. Optical identification and redshifts of Planck SZ sources with telescopes in the Canary Islands Observatories
• Optical Confirmation and Redshift Estimation of the Planck Cluster Candidates overlapping the Pan-STARRS Survey
• Optical identifications of high-redshift galaxy clusters from Planck Sunyaev-Zeldovich survey
• Optical validation and characterization of Planck PSZ1 sources at the Canary Islands observatories. I. First year of ITP13 observations
• Optical & Sunyaev-Zel'dovich Observations of a New Sample of Distant Rich Galaxy Clusters in the ROSAT All Sky Survey
• The Good, the Bad and the Ugly: Statistical quality assessment of SZ detections
• Characterization of a subsample of the Planck SZ source cluster catalogues using optical SDSS DR12 data
• Physical Properties of Four SZE-Selected Galaxy Clusters in the Southern Cosmology Survey
• Optical analysis of the poor clusters Abell 610, Abell 725, and Abell 796, containing diffuse radio sources
• An alternative validation strategy for the Planck cluster catalog and $y$-distortion maps
• Prospects for high-z cluster detections with Planck, based on a follow-up of 28 candidates using MegaCam@CFHT
• Environmental effects on the bright end of the galaxy luminosity function in galaxy clusters

Cited by in corpus (8)

• The Planck clusters in the LOFAR sky. I. LoTSS-DR2: new detections and sample overview
• Optical validation and characterization of Planck PSZ2 sources at the Canary Islands observatories. II. Second year of LP15 observations
• Deep learning for Sunyaev-Zel'dovich detection in Planck
• Velocity dispersion and dynamical masses for 388 Galaxy Clusters and groups. Calibrating the $M_{\mathrm{SZ}}$--$M_{\mathrm{dyn}}$ scaling relation for the PSZ2 sample
• The Clusters Hiding in Plain Sight (CHiPS) survey: Complete sample of extreme BCG clusters
• Marginalised Normal Regression: Unbiased curve fitting in the presence of x-errors
• Optical validation and characterisation of Planck PSZ1 sources at the Canary Islands observatories. II. Second year of ITP13 observations
• Galaxy clusters in the LoTSS-DR3: Catalogues and detection pipeline for diffuse radio emission