Description

The Panchromatic Hubble Andromeda Treasury is a Hubble Space Telescope Multi-cycle program to map roughly a third of M31’s star forming disk, using 6 filters covering from the ultraviolet through the near infrared. With HST’s resolution and sensitivity, the disk of M31 is resolved into more than 100 million stars, enabling a wide range of scientific endeavors.

The phat_v3.phot_mod and phat_v2.phot_mod tables have been crossmatched against our defualt reference datasets within a 1.5 arcsec radius, nearest neighbor only. These tables will appear with x1p5 in their name in our table browser. Example: phat_v3.x1p5__phot_mod__gaia_dr3__gaia_source.

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Goals

  • Star formation histories derived on 50-100 parsec scales
  • Improved stellar evolution models, calibrated at UV through NIR wavelengths
  • Well-defined catalogs of stellar clusters, at all ages
  • Characterization of variations in the stellar mass function from ~3 to 30 solar masses
  • Measurements of the mass function and age distributions of stellar clusters
  • Maps of extinction from dust, and characterization of the extinction law
  • Calibration of star formation indicators
  • Age dating of supernova remnants
  • Quantitative constraints on the coupling between star formation and the interstellar medium
  • Identification and characterization of variable stars
  • Kinematic decompositions of structural components
  • Cross-identification of multi-wavelength sources and emission line objects
PHAT Brick coverage:

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Data Releases

All PHAT data products are available as files from the MAST Archive.

The Data Lab service provided here is database access to the photometric catalog, including the combined photometry for phat_v2 and phat_v3 and the single epoch measurements for phat_v2.

Documentation for PHAT_v3 can be found in Williams, B.F. et al. 2023.
PHAT_v3 Summary
Area covered 0.5 deg2
Bands F275W, F336W (WFC3/UVIS), F475W, F814W (ACS/WFC), F110W, F160W (WFC3/IR)
Depth (5σ, F275W,F336W,F475W,F814W,F110W,F160W) 25.1, 24.8, 27.9, 27.1, 25.0, and 24.0 mag
Spatial resolution (F275W,F336W,F475W,F814W,F110W,F160W) ~0.08,0.08,0.1,0.1,0.25,0.25 arcsec
Number of objects ~137,000,000
Photometric precision ~1%
Astrometric accuracy ~5 mas
PHAT_v3 Tables
Table Name Description
phot_mod Combined average photometry
Documentation for PHAT_v2 can be found in Williams, B.F. et al. 2014.
PHAT_v2 Summary
Area covered 0.5 deg2
Bands F275W, F336W (WFC3/UVIS), F475W, F814W (ACS/WFC), F110W, F160W (WFC3/IR)
Depth (5σ, F275W,F336W,F475W,F814W,F110W,F160W) 25.1, 24.8, 27.9, 27.1, 25.0, and 24.0 mag
Spatial resolution (F275W,F336W,F475W,F814W,F110W,F160W) ~0.08,0.08,0.1,0.1,0.25,0.25 arcsec
Number of bricks 23
Number of objects ~117,000,000
Number of measurements ~7,500,000,000
Photometric precision ~1%
Astrometric accuracy ~5 mas
PHAT_v2 Tables
Table Name Description
phot_meas Individual photometric measurements, one row per measurement
phot_mod Combined average photometry

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Data Reduction

The PHAT survey, the data reduction procedure, and photometric pipeline are described in the following papers:

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