Mission Overview
Physics at High Angular resolution in Nearby GalaxieS - Catalogs (PHANGS-CAT)
Primary Investigator: Janice C. Lee
HLSP Authors: David Thilker, Bradley Whitmore, Janice C. Lee, Sinan Deger, Daniel Maschman, Kirsten Larson, Stephen Hannon, Aida Wofford, James Lilly, Jordan Turner, Kiana Henny, Hamid Hassani
Released: 2022-02-08
Updated: 2026-06-08
Primary Reference(s): Lee et al. 2022, Additional References
DOI: 10.17909/jray-9798
Citations: See ADS Statistics
Read Mes:
Overview
The PHANGS program is building a panchromatic dataset to enable the multi-phase, multi-scale study of star formation across nearby spiral galaxies. PHANGS combines Atacama Large Millimeter/submillimeter Array (ALMA) CO(2-1) mapping, Very Large Telescope/Multi Unit Spectroscopic Explorer (VLT/MUSE) optical spectroscopy, Hubble Space Telescope (HST) UV-optical imaging, and James Webb Space Telescope (JWST) infrared imaging among other supporting datasets. PHANGS is using these data to study the star formation cycle and various phases of the interstellar medium.
Here, the team provides catalog products from the PHANGS survey. The PHANGS-HST Treasury has yielded a V-band selected census of ~100,000 star clusters and compact associations across the disks of 38 spiral galaxies (plus 1 companion dwarf galaxy) at distances of 4-23 Mpc.
Data Release Notes
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Catalogs combining the previously released DR4 HST photometry, with improved estimates of age, mass, and reddening, provided for star clusters and compact associations across the full sample of 38 PHANGS-HST spiral galaxies (+1 companion galaxy). These catalogs include results for a total of ∼100,000 sources. The HST photometry is unchanged from DR4, while the physical properties are based on an enhanced SED-Treefit analysis that builds on the results first provided in DR3, using the methods described in Thilker et al. 2025, as introduced by Whitmore et al. 2023.
Catalogs for multi-scale associations (from Larson et al. 2023 - preferred over the compact association catalogs), and using additional JWST data, will be provided at a future date.
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Catalogs of the observed properties of star clusters and compact associations for the full sample of 38 PHANGS-HST spiral galaxies (plus 1 companion dwarf galaxy) are provided. The catalogs include photometry for a total of ~100,000 star clusters and associations (Maschmann, Lee, Thilker, Whitmore, et al. 2024).
Catalogs containing the physical properties based on SED fitting of the HST NUV-U-B-V-I photometry will be provided in an upcoming delivery.
Catalogs for multi-scale associations will be provided at some future date
Update 2024-06-17: Replaced NGC 1510 and 1512 files (now version v2) because of a bug in the pipeline.
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A set of catalogs for compact clusters (CLUST) and a separate set of catalogs for multi-scale associations for five galaxies (NGC 1433, NGC 1566, NGC 1559, NGC 3351, NGC 3627) are being released as part of DR3. These are described at different levels of detail in Lee et al. 2022, Whitmore et al. 2021, Thilker et al. 2022, and Larson et al. 2023.
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Visit the PHANGS-HST HLSP page for references and documentation. Links to image products are also provided in the main PHANGS data access table.
Completes the image product release for the full PHANGS-HST sample. It also provides convolutional neural network (CNN) models trained with deep transfer learning, for the classification of star clusters.
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Visit the PHANGS-HST HLSP page for references and documentation. Links to image products are also provided in the main PHANGS data access table.
Provides image products for observations in the NUV-U-B-V-I bands for 29 out of 38 PHANGS-HST galaxies.
PHANGS Data from JWST
15 December 2023: PHANGS-JWST processed images from Cycle 1 are now publicly available through https://archive.stsci.edu/hlsp/phangs-jwst
PHANGS Data From ALMA and MUSE
30 April 2021: Associated ALMA and MUSE data are now publicly available through the PHANGS CANFAR site or https://sites.google.com/view/phangs/home/data
Data Products Description
Data Products Descriptions
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These catalogs combine the previously released DR4 HST photometric measurements with enhanced physical properties (ages, masses, and reddening) for roughly 100,000 star clusters and compact associations across 39 galaxies (40 target fields).
Primary changes relative to DR3 and DR4 include:
- Concatenation of individual galaxy catalogs into survey-wide catalogs that include all galaxies. (Note: Individual files for each galaxy are NOT provided in the Data Access Table.)
- Updated physical properties based on improved HST SED fitting using the methods described in Thilker et al. (2025).
- Addition of exploratory physical properties based on SED fitting that incorporates both HST and JWST/NIRCam data, as described in Henny et al. (2025).
The catalog files have the following naming convention:
For the 4 PRIMARY files:
hlsp_phangs-cat_hst_acs-uvis_dr5-targets_<version>_<type-1>-<type-2>-primary.fitswhere:
- <version> = "v1" for version 1 of the DR5 catalogs,
- <type-1> = Type of file: "human" classified or "machine" learning classified,
- <type-2> = Type of file:
"class1+2" - symmetric and asymmetric clusters or "class3" - compact associations.
Examples: hlsp_phangs-cat_hst_acs-uvis_dr5-targets_v1_human-class1+2-primary.fits
For the 1 SUPPLEMENTAL file:
hlsp_phangs-cat_hst_acs-uvis_dr5-targets_<version>_supplemental.fitswhere:
- <version> = "v1" for version 1 of the DR5 catalogs
Example: hlsp_phangs-cat_hst_acs-uvis_dr5-targets_v1_supplemental.fits
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A set of 4 catalogs is provided for each of 40 targets: 37 individual galaxies + 1 companion dwarf galaxy (NGC 1510) + NGC 628C + NGC 628E. The two pointings for NGC628 (NGC628C and NGC628E) are treated as separate targets because the V-band observations were obtained with two different instruments (ACS and WFC3).
Changes relative to DR3 include (1) careful removal of artifacts (e.g., masks for bright stars, diffraction spikes) and non-clusters (e.g., background galaxies). This results in a 8% decrease in the size of the ML-classified DR3 catalogs. (2) Machine learning classifications for DR4 are determined using neural network models trained entirely on PHANGS sources and classifications as described in Hannon et al. (2023) (supersedes initial models of Wei et al. 2020). (3) Compact associations (class 3), as identified in the cluster pipeline, are provided in DR4. The completeness of associations in these catalog is likely low (see Lee et al. 2022, section 4.7). For science applications requiring complete samples of associations, multi-scale association catalogs generated using watershed algorithms (Larson et al. 2023, as provided in DR3) are recommended. Catalogs for multi-scale associations for 5 galaxies were provided in DR3, and catalogs for the remaining PHANGS galaxies may be provided at some future date.The catalog files have the following naming convention:
hlsp_phangs-cat_hst_<ins>_<target>_<filter>_<version>_<type>.fitswhere:
- <ins> = Name of instrument, either "uvis" or "acs-uvis" if both instruments used in the catalog
- <target> = Name of galaxy, e.g., "ngc1566"
- <filter> = "multi", since all the catalogs include data from several filters
- <version> = "v1" for version 1 of the catalogs
- <type> = Type of file:
- For CLUSTER (class 1 & 2) catalog files:
- 2x40 files: one file for each of 2 classification methods (human, machine) and 40 targets
- "obs-human-cluster-class12.fits"
- "obs-machine-cluster-class12.fits"
- For COMPACT ASSOCIATION (class 3) catalog files:
- 2x40 files: one file for each of 2 classification methods (human, machine) and 40 targets
- "obs-human-compact-association-class3.fits"
- "obs-machine-compact-association-class3.fits"
- For U-B-V-I DIAGRAM REGION DEFINITION files:
- 2x3 files: one file for each of 3 regions (YCL, MAP, OGC), and 2 classification methods (human, machine)
- "ycl-human-ubvi.txt" "map-human-ubvi.txt" "ogc-human-ubvi.txt
- "ycl-machine-ubvi.txt" "map-machine-ubvi.txt" "ogc-machine-ubvi.txt"
- For NUV-B-V-I DIAGRAM REGION DEFINITION files:
- 2x3 files: one file for each of 3 regions (YCL, MAP, OGC), and 2 classification methods (human, machine)
- "ycl-human-nuvbvi.txt" "map-human-nuvbvi.txt" "ogc-human-nuvbvi.txt"
- "ycl-machine-nuvbvi.txt" "map-machine-nuvbvi.txt" "ogc-machine-nuvbvi.txt"
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The catalog files have the following naming convention:
hlsp_phangs-cat_hst_<ins>_<target>_<filter>_<version>_<type>.fitswhere:
- <ins> = Name of instrument, either "wfc3" or "acs-wfc3" if both instruments used in the catalog
- <target> = Name of galaxy, e.g., "ngc1566"
- <filter> = "multi", since all the catalogs include data from several filters
- <version> = "v1" for version 1 of the catalogs
- <type> = Type of file:
- For CLUSTER files:
- one of "cluster-human-class12.fits" or "cluster-ml-class12.fits"
- For ASSOC files:
- At the galaxy level:
- "assoc-brightstarmask.reg" = circular regions used to eliminate objects around bright stars
- At the association level:
- "assoc-<selection band>-<scalepc>-main.fits" = main catalog
- "assoc-<selection band>-<scalepc>-idmask.fits" = segmentation map
- "assoc-<selection band>-<scalepc>-peaks.reg" = position of the peak flux in each region
- "assoc-<selection band>-<scalepc>-region.reg" = DS9 region file showing outline of the region
- where:
- <selection band> = wavelength band used for selection, one of "nuvselect" (F275W) or "vselect" (F555W)
- <scalepc> = the size scale in parsecs used to form associations (one of "ws8pc", "ws16pc", "ws32pc", or "ws64pc", where "ws" stands for "watershed method"
- At the galaxy level:
- For CLUSTER files:
Data file types:
_cluster-human-class12.fits human-classified cluster catalog, includes class 1 and class 2 clusters
_cluster-ml-class12.fits
machine-learning-classified cluster catalog, includes class 1 and class 2 clusters _assoc-brightstarmask.reg
bright star mask region file _assoc-<band>-<scalepc>-main.fits
multi-scale associaton catalog _assoc-<band>-<scalepc>-idmask.fits
segmentation map, values correspond to "ID" in the main catalog
_assoc-<band>-<scalepc>-peaks.reg
region file containing peak flux positions _assoc-<band>-<scalepc>-region.reg
region file containing outline of the region
Data Access
DR5 Summary Catalogs
HST DR5 cluster catalogs (includes all galaxies).
| PRIMARY DR5 cluster catalogs (includes all galaxies) | SUPPLEMENTAL catalog (includes additional detail) |
|---|---|
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Machine-Classifed: |
Supplemental Catalog: |
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Human-Classified: |
README: |
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README: |
DR4 - Catalog Release 2
Please see the data table on the PHANGS page for downloads for galaxy-specific cluster and compact association photometric catalogs.
DR3 - Catalog Release 1
Download tar files containing every CLUSTER or ASSOC product across all available galaxies in the table below. A copy of the README files are included in each tar file, but are also linked on their own for direct access in the table below. The README files explain the catalog columns in more detail, and also include information about the galactic extinction tables, aperture corrections, and assumed distances.
|
CLUSTER Bundle |
ASSOC Bundle |
|---|---|
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Catalogs: hlsp_phangs-cat_hst_wfc3_all_multi_v1_cc-cats.tar.gz |
Catalogs: hlsp_phangs-cat_hst_wfc3_all_multi_v1_assoc-cats.tar.gz |
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README: hlsp_phangs-cat_hst_wfc3_all_multi_v1_compact-cluster-readme.txt |
README: hlsp_phangs-cat_hst_wfc3_all_multi_v1_assoc-readme.txt |
Download tar files containing every CLUSTER or ASSOC product for a specific galaxy using the table below.
Information about the DR3 star cluster catalogs below may be of interest (this information is updated in DR4 and provided in Maschmann, Lee, Thilker, Whitmore, et al. submitted).
| Galaxy |
Distance (Mpc) |
m-M |
mv human_cutoff |
Mv human_cutoff |
human class1 |
human class2 |
mv machine_cutoff |
Mv machine_cutoff |
machine class1 |
machine class2 |
|---|---|---|---|---|---|---|---|---|---|---|
|
ngc1433 |
8.3 | 29.6 | 24.1 | -5.5 | 90 | 101 | 25.2 | -4.4 | 209 | 132 |
|
ngc1559 |
19.4 | 31.4 | 23.5 | -7.9 | 419 | 301 | 25.7 | -5.8 | 659 | 494 |
|
ngc1566 |
18.0 | 31.3 | 23.5 | -7.8 | 379 | 271 | 25.2 | -6.1 | 796 | 398 |
|
ngc3351 |
10.0 | 30.0 | 24.0 | -6.0 | 137 | 166 | 25.4 | -4.6 | 439 | 246 |
|
ngc3627 |
10.1 | 30.0 | 22.5 | -7.5 | 462 | 312 | 24.9 | -5.2 | 1725 | 820 |



















