Abell 2744 Observations, catalogs, and data products Authors: John R. Weaver, Sam Cutler, Richard Pan, Kate Whitaker, Wren Suess, and Lukas Furtak Release: 3 Version: 5.2.0 Created: 12 December 2022 Last Updated: 24 April 2024 If you use these catalogs, please cite the corresponding papers: Suess et al. 2024 (https://ui.adsabs.harvard.edu/abs/2024arXiv240413132S/abstract), Weaver et al. 2023 (https://ui.adsabs.harvard.edu/abs/2023arXiv230102671W/abstract), Bezanson et al. 2024 (https://ui.adsabs.harvard.edu/abs/2022arXiv221204026B/abstract). A frozen version of these catalogs are available on Zenodo in perpetuity (https://doi.org/10.5281/zenodo.10987924). AVAILABLE FILES ------------ ├── README_DR3.txt :: this file ├── Weaver+2023.pdf :: Pre-print of the corresponding paper ├── UNCOVER_DR3_LW_DETECTION.fits.gz :: LW noise-equalized detection image (F277W + F356W + F444w; 40mas scale) ├── UNCOVER_DR3_LW_SEGMAP.fits.gz :: Segmentation map corresponding to source IDs (40mas scale) ├── UNCOVER_DR3_LW_SUPER_catalog.fits :: Recommended photometric catalog with most suitable aperture sizes ├── niriss_parallel.zip :: Catlogs of the NIRISS parallel field with a parallel directory structure and README ├── UNCOVER_DR3_LW_DETECTION_objects.reg :: Region file showing all objects ├── UNCOVER_DR3_LW_SUPER_objects.reg :: Region file showing color aperture (+ Kron ellipse, where applicable) for USE_PHOT = 1 sources ├── UNCOVER_DR3_LW_zphot.translate :: Translate file for EAZY ├── UNCOVER_DR3_kernels.tar.gz :: F444W matching kernels (40mas scale) ├── UNCOVER_DR3_psfs.tar.gz :: Observed point spread functions (40mas scale) ├── UNCOVER_DR3_LW_D032_catalog.fits :: Photometric catalog with 0.32" diameter color apertures ├── UNCOVER_DR3_LW_D048_catalog.fits :: Photometric catalog with 0.48" diameter color apertures ├── UNCOVER_DR3_LW_D070_catalog.fits :: Photometric catalog with 0.70" diameter color apertures ├── UNCOVER_DR3_LW_D100_catalog.fits :: Photometric catalog with 1.00" diameter color apertures └── UNCOVER_DR3_LW_D140_catalog.fits :: Photometric catalog with 1.40" diameter color apertures RECOMMENDED USE ------------ Please use the 'SUPER' catalog. Fluxes are extracted in color apertures suitable for the a particular object. 78% of objects are assigned the smallest 0.32" diameter aperture. ABOUT APERPY --------- Aperpy is an aperture photometry software which utilizes source detection and photometry from SEP (Barbary et al. 2016) with aperture corrections broadly following Whitaker et al. 2011. It follows a modular structure written entirely in python allow for flexibility and coherent pipeline flow commanded from a single configuration file. More details below. Aperpy is generally applicable to any JWST/NIRCam data and can be freely accessed though Github (https://github.com/astrowhit/aperpy) and Zenodo (https://doi.org/10.5281/zenodo.8280270). DETECTION: --------- We adopt a 56 sq. arcmin. Long-Wavelength (LW) Detection (F277W+F356W+F444W) combined using a noise-equalized technique. A total of 74,020 sources are detected. MOSAICS/BANDS: ------------ This catalog extracts fluxes from mosaics where the bright Cluster Galaxies (bCGs) have been modelled and removed, see the bCG README and/or catalog paper for details. The mosaics were then PSF-matched (see below). Mosaics units are Fnu, 10*nJy (AB zpt=28.9). Note: catalog fluxes are Fnu ALSO have zpt = 28.9 Note that all mosaics are measured at 0.04"/pixel scale. For SW mosaics produced at 0.02"/px, pixels are co-added to scale to 0.04"/pixel. Grizli mosaics (v7.0, v7.1, v7.2): https://s3.amazonaws.com/grizli-v2/JwstMosaics/v7/index.html Contribuing JWST datasets: * UNCOVER (PIs: Labbe & Bezanson, Bezanson et al. 2023) * GLASS/ERS-X1324 (PI: Treu, Treu et al. 2022) * GO-3990 (PI: Morshita) * ALT (PIs Matthee & Naidu) * MAGNIF (PI: Sun) * GO-3538 (PI: Iani) * GTO-PERALS/GTO-1176 (PI: Windhorst) * DD-2756 (PI: Chen) Please see the NIRISS zip file for details of the parallel release field. PSF MATCHING: ------------ For sources identified in each detection strategy, we perform photometry on both a set of a images PSF-matched to F444W. To prepare the PSF matched images, both the JWST and HST PSFs were constructed directly from stars in the FOV (see paper for details). Stamps are 4" FOV at 0.04"/pixel. The HST PSFs are not amazing in some of the bands with less coverage but sufficient for these purposes and the growth curves agreed to the 1% level or less (for most HST/JWST bands). For recommended methods, see https://github.com/astrowhit/aperpy/blob/main/src/convolve_images.py FLUXS & ERRORS: ------------- Fluxes are measured separately in both 0.32", 0.48", 0.70", 1.00", and 1.40" diameter apertures that are corrected to total fluxes based on the Kron Radius measured in F277W+F356W+F444W stack plus a roughly 5-10% correction from Kron to total to account for missing light beyond 1" radius based on the F444W curve of growth. A wavelength dependent correction for galactic extinction at the position of Abell 2744 has been applied (of order 2% and less). Errors are calculated with empty apertures where the conversion from the aperture error to total flux error is based on F444W filter and noise properties. All fluxes have a unit of 10 * nJy with a corresponding AB magnitude zeropoint of 28.9. Photometry for significantly blended objects (flag_kron = 1) is computed without kron (so color -> total via the PSF curve of growth). Blends are identified by SEP, but those which are the brightest sources within their blends as determined by isophotal (segment) fluxes are not considered blends so long as the area of their kron ellipse is within 50% of their isophotal area. Objects whose kron ellipse areas are less than their isophotal areas are also not considered blends. A SUPER catalog combines the five catalogs with adaptive aperture selection based on their isophotal areas (see Labbe et al. 2003). Apertures for objects which are considered blends are selected based on a conservative 20% reduction of their isophotal area to ensure robust colors. We also include photometry from ALMA (Fujimoto+23) for sources found in our catalog (nearest within 1"). 1 sigma upper limits are reported for non-detections. STAR-GALAXY SEPARATION: ----------- Stars are flagged as 'flag_star' == 1. They are identified as satisfying at least one of the following of criteria: 1. Having a F200W flux ratio in 0.7" / 0.32" apertures between 1.0 and 1.2 & brighter than 25.0 AB in 0.7" apertures 2. Having a F160W flux ratio in 1.4" / 0.7" apertures between 1.0 and 1.2 & brighter than 23.8 AB in 0.7" apertures For completeness, we also adopt stars chosen detected directly from the F160W mosaics, as those with significant proper motions are shifted from their JWST-detected centroids. Lastly, we flag any source in any band that was included in our more conservative selection that contribute to our PSF stacks. ARTIFACTS: ------------ Artifacts are flagged as 'flag_artifact' == 1. The bCG and ICL subtraction leaves residuals which can be wrongly classified as real sources. We flag any source within 3" radius of a known bCG centroid as an artifact. Although the most severe residuals are now flagged, there are still some artifacts detected along residuals (notably diffraction spikes) at larger radii. These regions may still contain useful objects, and so we provide an additional flag (flag_nearbcg) so users can re-introduce these sources if interested. Visual inspection is strongly advised. In addition, there appear to be a number of bad pixels in the LW channels (F277W - F444W) which can appear as bright SW-dropouts. to mitigate contamination we flag bad pixels as having a F444W flux ratio in 0.7" / 0.32" apertures below 1.1 brighter than 26.0 AB in 0.32" apertures. There are also a number of detections near mosaic edges where detector effects cause data loss, seen as regions of zeros in the detection weight map. We flag any object within 3" radius of such a region whose area is between 10 and 1000 pixels, calibrated visually. Lastly, we manually flag regions around bright stars and their diffraction spikes. This is particularly useful for the brightest stars that are saturated, meaning they can not be identified from photometry and often cause multiple false detections near their saturated cores. A copy of the region file is provided. USE_PHOT: ------------ We provide a 'use_phot' flag to separate robust sources (use_phot = 1) from objects that are stars, artifacts, are marginally detected, or have no usable photometry (use_phot = 0). Marginally detected sources, based a signal-to-noise < 3 in the detection image, are also denoted by the 'flag_lowsnr' flag. A handful of sources have no usable photometry. This is particularly prevalent in the larger aperture catalogs where the aperture either contains a bad pixel or the edge of the mosaic. For the 'SUPER' catalog, we include the most suitable aperture size, but may include a smaller size if the most suitable one is unusable for either of these reasons. PHOTO-Z: ------------ Quick-look photometric redshifts are estimated using EAZY and are available for the SUPER catalog as well as single aperture catalogs. Estimates include redshifts, a handful of rest-frame fluxes (in Fnu, 10*nJy), and the chi2 of the best-fit PHOENIX stellar template. The corresponding "translate" file is included for easy re-fitting of objects. Note that priors on magnitude and UV slope as well and iterative zeropoint corrections are not applied. We include only estimates determined from the 'SFHZ_BLUE_AGN' templates as they apply redshift constraints to exclude nonphysical solutions and include support for obscured AGN. We caution that redshifts may be underestimated for cluster systems at z < 0.5. For more detailed spectral fitting, we refer the reader to redshifts and physical parameters derived from Prospector-Beta released as part of DR3. Spectroscopic redshifts are taken from the compilation of Shipley et al. 2018 (see also Kokorev et al. 2022), adopting only secure matches (flag 3 or 4, as per convention) within 0.3" radius. Spectroscopic redshifts obtained with UNCOVER MSA are *not* included at this time. MAGNIFICATION: ------------ No magnification estimates are computed on the NIRISS parallel field CATALOG FORMAT: ------------ id :: object identification number x/y :: centroid position in image frame ra/dec :: centroid position in world frame ebv_mw :: MW attenuation correction in E(B-V) computed from Schlafly & Finkbeiner (2011) faper_f277w+f356w+f444w: flux computed in circular aperture of size corresponding to filename, in 10*nJy (Fnu) corresponding to ABMag zpt=28.9 eaper_f277w+f356w+f444w: flux error computed from empty apertures (same size as above), scaled by local weight / median weight fauto_f277w+f356w+f444w: w_f277w+f356w+f444w: weight at the position of the source relative to the maximum weight (i.e. large values --> deep regions) f_fXXXw :: total flux computed in circular aperture corrected using circularized Kron radius, in 10*nJy (Fnu) corresponding to ABMag zpt=28.9 e_fXXXw :: total flux error computed from empty apertures (same size as above), corrected to total using circularized kron radius w_fXXXw :: weight at the position of the source relative to the maximum weight (i.e. large values --> deep regions) tot_cor :: aperture to total correction based on circularized kron radius kron_radius :: kron "factor" (unitless) kron_radius_circ :: circularized kron radius in arcsec use_circle :: 1 when no kron factor is applied (most are due to unreliable kron radii, but some are just small point-like things) flag_kron :: 1 when kron radius is not robust, in which case total photometry assumes point-like light distribution iso_area :: isophotal area based on the source segment in sq. arcsec use_aper :: (SUPER catalog only) indicates arcsec diameter adopted for color aperture a_image :: semi-major axis in pixels b_image :: semi-minor axis in pixels theta_J2000 :: position angle in degrees clockwise from the first image axis (along y) flux_radius :: radius containing 50% of the flux in arcseconds use_phot :: 1 if photometry is reliable (f444w SNR > 3, not a star, not likely a bad pixel) flag_nophot :: 1 if the object has no viable photometry in any band at this aperture size flag_lowsnr :: 1 if S/N < 3 in the f277W+f356w+f444w stack flag_star :: stellarity flag (see above) flag_artifact :: 1 if bad pixel, bCG-subtraction residual, or image artifact (see above) flag_nearbcg :: 1 if source is within 3" of a subtracted bCG (likely a residual artifact) z_spec :: spectroscopic redshift (matched within 0.3" radius, see above for details) id_DR2 :: ID of the source in the DR2 catalog release (all within < 0.08" radius) match_radius_DR2 :: radius in arcsec to DR2 catalog release match id_msa :: ID of the source in the team internal msa catalog (all within < 0.24" radius) match_radius_msa :: radius in arcsec to team internal msa catalog match id_alma :: ID of ALMA source from Fujimoto+23 f_alma :: ALMA flux (NaN for non-detections), in 10*nJy (Fnu) corresponding to ABMag zpt=28.9 e_alma :: ALMA flux uncertainty (1 sigma upper limit for non-detections), in 10*nJy (Fnu) corresponding to ABMag zpt=28.9 match_radius_alma :: radius in arcsec to this catalog (nearest within 1" radius) nusefilt :: number of filters used in the fit z_phot :: best-fit photometric redshift (maximum likelihood) z_phot_chi2 :: total chi-squared at z_phot z025/160/500/840/975 :: percentiles of P(z), e.g. z025 -> 2.5% (redshift posterior) restU :: rest-frame U-band flux (same as photometry: Fnu, units corresponding to ABmag = 28.9) restU_err :: rest-frame U-band flux uncertainty (same as photometry: Fnu, units corresponding to ABmag = 28.9) restV :: rest-frame V-band flux (same as photometry: Fnu, units corresponding to ABmag = 28.9) restV_err :: rest-frame V-band flux uncertainty (same as photometry: Fnu, units corresponding to ABmag = 28.9) restJ :: rest-frame J-band flux (same as photometry: Fnu, units corresponding to ABmag = 28.9) restJ_err :: rest-frame J-band flux uncertainty (same as photometry: Fnu, units corresponding to ABmag = 28.9) restus :: rest-frame synth. u-band flux (same as photometry: Fnu, units corresponding to ABmag = 28.9) restus_err :: rest-frame synth. u-band flux uncertainty (same as photometry: Fnu, units corresponding to ABmag = 28.9) restgs :: rest-frame synth. g-band flux (same as photometry: Fnu, units corresponding to ABmag = 28.9) restgs_err :: rest-frame synth. g-band flux uncertainty (same as photometry: Fnu, units corresponding to ABmag = 28.9) restis :: rest-frame synth. i-band flux (same as photometry: Fnu, units corresponding to ABmag = 28.9) restis_err :: rest-frame synth. i-band flux uncertainty (same as photometry: Fnu, units corresponding to ABmag = 28.9) star_min_chi2 :: chi2 of best-fit stellar template flag_eazy :: 1 if fit is reliable z_use :: redshift used to compute magnification (z_phot unless is_zspec == 1) is_zspec :: 1 if the reddshfit comes from z_spec, 0 otherwise mu :: magnification (best-fit; = 1 for foreground objects) mu025/160/840/975 :: magnification uncertainty percentiles mu_r :: Radial magnification (best-fit; = 1 for foreground objects) mu_r025/160/840/975 :: Radial magnification posterior percentiles mu_t :: Tangential magnification (best-fit; = 1 for foreground objects) mu_t025/160/840/975 :: Tangential magnification posterior percentiles shearone :: Shear gamma_1 (best-fit; = 1 for foreground objects) shearone025/160/840/975 :: Shear gamma_1 posterior percentiles sheartwo :: Shear gamma_2 (best-fit; = 1 for foreground objects) sheartwo025/160/840/975 :: Shear gamma_2 posterior percentiles