THE GHOSTS SURVEY. I. HUBBLE SPACE TELESCOPE ADVANCED CAMERA FOR SURVEYS DATA

Journal Article · Mon Aug 01 04:00:00 EDT 2011 · Astrophysical Journal, Supplement Series

DOI:https://doi.org/10.1088/0067-0049/195/2/18· OSTI ID:21562465

Radburn-Smith, D J; Dalcanton, J J ^[1]; De Jong, R S; Streich, D; Vlajic, M ^[2]; Seth, A C ^[3]; Bailin, J; Bell, E F ^[4]; Brown, T M; Ferguson, H C; Goudfrooij, P; Holfeltz, S ^[5]; Bullock, J S ^[6]; Courteau, S; Sick, J ^[7]; Holwerda, B W ^[8]; Purcell, C ^[9]; Zucker, D B ^[10]

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1. Department of Astronomy, University of Washington, Seattle, WA 98195 (United States)
2. Leibniz-Institut fuer Astrophysik Potsdam, D-14482 Potsdam (Germany)
3. Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States)
4. Department of Astronomy, University of Michigan, Ann Arbor, MI 48109 (United States)
5. Space Telescope Science Institute, Baltimore, MD 21218 (United States)
6. Center for Cosmology, Department of Physics and Astronomy, University of California at Irvine, Irvine, CA 92697 (United States)
7. Department of Physics, Engineering Physics and Astronomy, Queen's University, Kingston, ON K7L 3N6 (Canada)
8. European Space Agency, ESTEC, 2200 AG Noordwijk (Netherlands)
9. Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, PA 15260 (United States)
10. Department of Physics and Astronomy, Macquarie University, NSW 2109 (Australia)

We present an overview of the GHOSTS survey, the largest study to date of the resolved stellar populations in the outskirts of disk galaxies. The sample consists of 14 disk galaxies within 17 Mpc, whose outer disks and halos are imaged with the Hubble Space Telescope Advanced Camera for Surveys (ACS). In the first paper of this series, we describe the sample, explore the benefits of using resolved stellar populations, and discuss our ACS F606W and F814W photometry. We use artificial star tests to assess completeness and use overlapping regions to estimate photometric uncertainties. The median depth of the survey at 50% completeness is 2.7 mag below the tip of the red giant branch (TRGB). We comprehensively explore and parameterize contamination from unresolved background galaxies and foreground stars using archival fields of high-redshift ACS observations. Left uncorrected, these would account for 10{sup 0.65xF814W-19.0} detections per mag per arcsec{sup 2}. We therefore identify several selection criteria that typically remove 95% of the contaminants. Even with these culls, background galaxies are a significant limitation to the surface brightness detection limit which, for this survey, is typically V {approx} 30 mag arcsec{sup -2}. The resulting photometric catalogs are publicly available and contain some 3.1 million stars across 76 ACS fields, predominantly of low extinction. The uniform magnitudes of TRGB stars in these fields enable galaxy distance estimates with 2%-7% accuracy.

• OSTI ID: 21562465
• Journal Information: Astrophysical Journal, Supplement Series, Journal Name: Astrophysical Journal, Supplement Series Journal Issue: 2 Vol. 195; ISSN 0067-0049; ISSN APJSA2
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
CAMERAS
CATALOGS
DOCUMENT TYPES
GALAXIES
PHOTOMETRY
STARS
TELESCOPES