TY - JOUR
T1 - The Panchromatic Hubble Andromeda Treasury
AU - Dalcanton, Julianne J.
AU - Williams, Benjamin F.
AU - Lang, Dustin
AU - Lauer, Tod R.
AU - Kalirai, Jason S.
AU - Seth, Anil C.
AU - Dolphin, Andrew
AU - Rosenfield, Philip
AU - Weisz, Daniel R.
AU - Bell, Eric F.
AU - Bianchi, Luciana C.
AU - Boyer, Martha L.
AU - Caldwell, Nelson
AU - Dong, Hui
AU - Dorman, Claire E.
AU - Gilbert, Karoline M.
AU - Girardi, Léo
AU - Gogarten, Stephanie M.
AU - Gordon, Karl D.
AU - Guhathakurta, Puragra
AU - Hodge, Paul W.
AU - Holtzman, Jon A.
AU - Johnson, L. Clifton
AU - Larsen, Sorens
AU - Lewis, Alexia
AU - Melbourne, Jason L.
AU - Olsen, Knut A.G.
AU - Rix, Hans Walter
AU - Rosema, Keith
AU - Saha, Abhijit
AU - Sarajedini, Ata
AU - Skillman, Evan D.
AU - Stanek, Krzysztof Z.
PY - 2012/6
Y1 - 2012/6
N2 - The Panchromatic Hubble Andromeda Treasury is an ongoing Hubble Space Telescope Multi-Cycle Treasury program to image 1/3 of M31's star-forming disk in six filters, spanning from the ultraviolet (UV) to the near-infrared (NIR). We use the Wide Field Camera 3 (WFC3) and Advanced Camera for Surveys (ACS) to resolve the galaxy into millions of individual stars with projected radii from 0 to 20 kpc. The full survey will cover a contiguous 0.5deg 2area in 828 orbits. Imaging is being obtained in the F275W and F336W filters on the WFC3/UVIS camera, F475W and F814W on ACS/WFC, and F110W and F160W on WFC3/IR. The resulting wavelength coverage gives excellent constraints on stellar temperature, bolometric luminosity, and extinction for most spectral types. The data produce photometry with a signal-to-noise ratio of 4 at m F275W = 25.1, m F336W = 24.9, m F475W = 27.9, m F814W = 27.1, m F110W = 25.5, and m F160W = 24.6 for single pointings in the uncrowded outer disk; in the inner disk, however, the optical and NIR data are crowding limited, and the deepest reliable magnitudes are up to 5mag brighter. Observations are carried out in two orbits per pointing, split between WFC3/UVIS and WFC3/IR cameras in primary mode, with ACS/WFC run in parallel. All pointings are dithered to produce Nyquist-sampled images in F475W, F814W, and F160W. We describe the observing strategy, photometry, astrometry, and data products available for the survey, along with extensive testing of photometric stability, crowding errors, spatially dependent photometric biases, and telescope pointing control. We also report on initial fits to the structure of M31's disk, derived from the density of red giant branch stars, in a way that is independent of assumed mass-to-light ratios and is robust to variations in dust extinction. These fits also show that the 10 kpc ring is not just a region of enhanced recent star formation, but is instead a dynamical structure containing a significant overdensity of stars with ages >1 Gyr.
AB - The Panchromatic Hubble Andromeda Treasury is an ongoing Hubble Space Telescope Multi-Cycle Treasury program to image 1/3 of M31's star-forming disk in six filters, spanning from the ultraviolet (UV) to the near-infrared (NIR). We use the Wide Field Camera 3 (WFC3) and Advanced Camera for Surveys (ACS) to resolve the galaxy into millions of individual stars with projected radii from 0 to 20 kpc. The full survey will cover a contiguous 0.5deg 2area in 828 orbits. Imaging is being obtained in the F275W and F336W filters on the WFC3/UVIS camera, F475W and F814W on ACS/WFC, and F110W and F160W on WFC3/IR. The resulting wavelength coverage gives excellent constraints on stellar temperature, bolometric luminosity, and extinction for most spectral types. The data produce photometry with a signal-to-noise ratio of 4 at m F275W = 25.1, m F336W = 24.9, m F475W = 27.9, m F814W = 27.1, m F110W = 25.5, and m F160W = 24.6 for single pointings in the uncrowded outer disk; in the inner disk, however, the optical and NIR data are crowding limited, and the deepest reliable magnitudes are up to 5mag brighter. Observations are carried out in two orbits per pointing, split between WFC3/UVIS and WFC3/IR cameras in primary mode, with ACS/WFC run in parallel. All pointings are dithered to produce Nyquist-sampled images in F475W, F814W, and F160W. We describe the observing strategy, photometry, astrometry, and data products available for the survey, along with extensive testing of photometric stability, crowding errors, spatially dependent photometric biases, and telescope pointing control. We also report on initial fits to the structure of M31's disk, derived from the density of red giant branch stars, in a way that is independent of assumed mass-to-light ratios and is robust to variations in dust extinction. These fits also show that the 10 kpc ring is not just a region of enhanced recent star formation, but is instead a dynamical structure containing a significant overdensity of stars with ages >1 Gyr.
KW - galaxies: individual (M31)
KW - galaxies: stellar content
KW - stars: general
KW - stars: imaging
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U2 - 10.1088/0067-0049/200/2/18
DO - 10.1088/0067-0049/200/2/18
M3 - Article
AN - SCOPUS:84861833036
SN - 0067-0049
VL - 200
JO - Astrophysical Journal, Supplement Series
JF - Astrophysical Journal, Supplement Series
IS - 2
M1 - 18
ER -