TY - JOUR
T1 - The panchromatic hubble andromeda treasury. X. Ultraviolet to infrared photometry of 117 million equidistant stars
AU - Williams, Benjamin F.
AU - Lang, Dustin
AU - Dalcanton, Julianne J.
AU - Dolphin, Andrew E.
AU - Weisz, Daniel R.
AU - Bell, Eric F.
AU - Bianchi, Luciana
AU - Byler, Nell
AU - Gilbert, Karoline M.
AU - Girardi, Léo
AU - Gordon, Karl
AU - Gregersen, Dylan
AU - Johnson, L. C.
AU - Kalirai, Jason
AU - Lauer, Tod R.
AU - Monachesi, Antonela
AU - Rosenfield, Philip
AU - Seth, Anil
AU - Skillman, Eva
N1 - Publisher Copyright:
© 2014. The American Astronomical Society. All rights reserved.
PY - 2014/10/1
Y1 - 2014/10/1
N2 - We have measured stellar photometry with the Hubble Space Telescope Wide Field Camera 3 (WFC3) and Advanced Camera for Surveys in near ultraviolet (F275W, F336W), optical (F475W, F814W), and near infrared (F110W, F160W) bands for 117 million resolved stars in M31. As part of the Panchromatic Hubble Andromeda Treasury survey, we measured photometry with simultaneous point-spread function (PSF) fitting across all bands and at all source positions after precise astrometric image alignment (<5-10 mas accuracy). In the outer disk, the photometry reaches a completeness-limited depth of F475W 28, while in the crowded, high surface brightness bulge, the photometry reaches F475W 25. We find that simultaneous photometry and optimized measurement parameters significantly increase the detection limit of the lowest-resolution filters (WFC3/IR) providing color-magnitude diagrams (CMDs) that are up to 2.5 mag deeper when compared with CMDs from WFC3/IR photometry alone. We present extensive analysis of the data quality including comparisons of luminosity functions and repeat measurements, and we use artificial star tests to quantify photometric completeness, uncertainties and biases. We find that the largest sources of systematic error in the photometry are due to spatial variations in the PSF models and charge transfer efficiency corrections. This stellar catalog is the largest ever produced for equidistant sources, and is publicly available for download by the community.
AB - We have measured stellar photometry with the Hubble Space Telescope Wide Field Camera 3 (WFC3) and Advanced Camera for Surveys in near ultraviolet (F275W, F336W), optical (F475W, F814W), and near infrared (F110W, F160W) bands for 117 million resolved stars in M31. As part of the Panchromatic Hubble Andromeda Treasury survey, we measured photometry with simultaneous point-spread function (PSF) fitting across all bands and at all source positions after precise astrometric image alignment (<5-10 mas accuracy). In the outer disk, the photometry reaches a completeness-limited depth of F475W 28, while in the crowded, high surface brightness bulge, the photometry reaches F475W 25. We find that simultaneous photometry and optimized measurement parameters significantly increase the detection limit of the lowest-resolution filters (WFC3/IR) providing color-magnitude diagrams (CMDs) that are up to 2.5 mag deeper when compared with CMDs from WFC3/IR photometry alone. We present extensive analysis of the data quality including comparisons of luminosity functions and repeat measurements, and we use artificial star tests to quantify photometric completeness, uncertainties and biases. We find that the largest sources of systematic error in the photometry are due to spatial variations in the PSF models and charge transfer efficiency corrections. This stellar catalog is the largest ever produced for equidistant sources, and is publicly available for download by the community.
KW - Galaxies: stellar content
KW - Local Group
KW - Surveys
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U2 - 10.1088/0067-0049/215/1/9
DO - 10.1088/0067-0049/215/1/9
M3 - Article
AN - SCOPUS:84908512144
SN - 0067-0049
VL - 215
JO - Astrophysical Journal, Supplement Series
JF - Astrophysical Journal, Supplement Series
IS - 1
M1 - 9
ER -