Data Products - ACT DR5 Clusters Catalog - v1.0b3

This is a pre-release version of the data products associated with the ACT DR5 cluster catalog paper (Hilton et al. 2020).

The following data products are made available with this release:


Cluster Catalog

The file DR5_cluster-catalog_v1.0b3.fits is a FITS table that contains the ACT DR5 cluster catalog as described in Hilton et al. (2020). It can be viewed with any compatible viewer, e.g., TopCat, or read into Python using the astropy.table module.

The table columns contain the following information:

Column Description
name Cluster name in the format ACT-CL JHHMM.m±DDMM.
RADeg Right Ascension in decimal degrees (J2000) of the SZ detection by ACT.
decDeg Declination in decimal degrees (J2000) of the SZ detection by ACT.
SNR Signal-to-noise ratio, optimized over all filter scales.
y_c Central Comptonization parameter (× 10-4) measured using the optimal matched filter template (i.e., the one that maximizes SNR). Uncertainty column(s): err_y_c.
fixed_SNR Signal-to-noise ratio at the reference 2.4′ filter scale.
fixed_y_c Central Comptonization parameter (× 10-4) measured at the reference filter scale (2.4′). Uncertainty column(s): fixed_err_y_c.
template Name of the matched filter template resulting in the highest SNR detection of this cluster.
tileName Name of the ACT map tile (typically with dimensions 10 × 5 deg) in which the cluster was found.
redshift Adopted redshift for the cluster. The uncertainty is only given for photometric redshifts. Uncertainty column(s): redshiftErr.
redshiftType Redshift type (spec = spectroscopic, phot = photometric).
redshiftSource Source of the adopted redshift.
M500 M500c in units of 1014M, assuming the UPP and Arnaud et al. (2010) scaling relation to convert SZ signal to mass. Uncertainty column(s): M500_errPlus, M500_errMinus.
M500Cal M500c in units of 1014M, rescaled using the richness-based weak-lensing mass calibration factor of 0.69 ± 0.07. Uncertainty column(s): M500Cal_errPlus, M500Cal_errMinus.
M200m M200 with respect to the mean density, in units of 1014M, converted from M500c using the Bhattacharya et al. (2013) c-M relation. Uncertainty column(s): M200m_errPlus, M200m_errMinus.
M500Uncorr M500c in units of 1014M, assuming the UPP and Arnaud et al. (2010) scaling relation to convert SZ signal to mass, uncorrected for bias due to the steepness of the cluster mass function. Uncertainty column(s): M500Uncorr_errPlus, M500Uncorr_errMinus.
M200mUncorr M200 with respect to the mean density, in units of 1014M, converted from M500c using the Bhattacharya et al. (2013) c-M relation, uncorrected for bias due to the steepness of the cluster mass function. Uncertainty column(s): M200mUncorr_errPlus, M200mUncorr_errMinus.
footprint_DESY3 Flag indicating if the cluster falls within the DES Y3 footprint.
footprint_HSCs19a Flag indicating if the cluster falls within the HSC-SSP S19A footprint.
footprint_KiDSDR4 Flag indicating if the cluster falls within the KiDS DR4 footprint.
zCluster_delta Density contrast statistic measured at the zCluster photometric redshift. Uncertainty column(s): zCluster_errDelta.
zCluster_source Photometry used for zCluster measurements. One of: DECaLS (DR8), KiDS (DR4), SDSS (DR12).
RM Flag indicating cross-match with a redMaPPer-detected cluster in the SDSS footprint (Rykoff et al. 2014).
RM_LAMBDA Optical richness measurement for the redMaPPer algorithm in the SDSS footprint. Uncertainty column(s): RM_LAMBDA_ERR.
RMDESY3 Flag indicating cross-match with a redMaPPer-detected cluster in the DES Y3 footprint (Rykoff et al. 2016).
RMDESY3_LAMBDA_CHISQ Optical richness measurement for the redMaPPer algorithm in the DES Y3 footprint. Uncertainty column(s): RMDESY3_LAMBDA_CHISQ_E.
CAMIRA Flag indicating cross-match with a CAMIRA-detected cluster in the HSCSSP S19A footprint (Oguri et al. 2018).
CAMIRA_N_mem Optical richness measurement for the CAMIRA algorithm in the HSCSSP S19A footprint.
opt_RADeg Alternative optically-determined Right Ascension in decimal degrees (J2000), from a heterogeneous collection of measurements (see opt\_positionSource).
opt_decDeg Alternative optically-determined Declination in decimal degrees (J2000), from a heterogeneous collection of measurements (see opt\_positionSource).
opt_positionSource Indicates the source of the alternative optically-determined cluster position. One of: AMICO (position from the AMICO cluster finder; \citealt2019MNRAS.485..498M), CAMIRA (position from the CAMIRA cluster finder; \citealtOguri_2018), RM, RMDESY3, RMDESY3ACT (position from the redMaPPer cluster finder, in SDSS, DES Y3, or DES Y3 using the ACT position as a prior; \citealtRykoff_2014, Rykoff_2016), Vis-BCG (BCG position from visual inspection of available optical/IR imaging; this work), WHL2015 (position from \citealtWH_2015).
notes If present, at least one of: AGN? (central galaxy may have color or spectrum indicating it may host an AGN); Lensing? (cluster may show strong gravitational lensing features); Merger? (cluster may be a merger); Star formation? (a galaxy near the center may have blue colors which might indicate star formation if it is not a line-of-sight projection). These notes are not comprehensive and merely indicate some systems that were identified as potentially interesting during visual inspection of the available optical/IR imaging.
knownLens Names of known strong gravitational lenses within 2 Mpc projected distance of this cluster (comma delimited when there are multiple matches).
knownLensRefCode Reference codes (comma delimited when there are multiple matches) corresponding to the entries in the knownLens field. See Table~\reftab:lensCodes to map between the codes used in this field and references to the corresponding lens catalog papers.
warnings If present, a warning message related to the redshift measurement for this cluster.

Catalog of multiple systems (cluster pairs and potential superclusters)

The file DR5_multiple-systems_v1.0b3.fits is a FITS table that contains the catalog of multiple systems and potential superclusters, assembled as described in Hilton et al. (2020). It can be viewed with any compatible viewer, e.g., TopCat, or read into Python using the astropy.table module.

The table columns contain the following information:

Column Description
name Name of the multiple system; constructed from the names of the individual clusters as given in the cluster catalog.
meanRADeg Mean Right Ascension in decimal degrees (J2000) of the clusters forming the multiple system.
meanDecDeg Mean Declination in decimal degrees (J2000) of the clusters forming the multiple system.
meanRedshift Mean of the redshifts of the individual clusters that make up the multiple system.
numClusters The number of clusters that make up the multiple system.
maxSeparationMpc The projected distance in Mpc (at the median redshift) between the two most widely separated components of the multiple system.
maxSeparationArcmin The angular separation in arcmin between the two most widely separated components of the multiple system.
includesPhotoRedshift Flag indicating that the multiple system includes at least one cluster that has only a photometric redshift estimate.
tileName Name(s) of the ACT map tile(s) (typically with dimensions 10 × 5 deg) in which each component of the multiple system was found.

Please contact Matt Hilton with any questions or comments.