Sign on

SAO/NASA ADS Astronomy Abstract Service


· Find Similar Abstracts (with default settings below)
· Electronic Refereed Journal Article (HTML)
· arXiv e-print (arXiv:astro-ph/9911193)
· On-line Data
· References in the article
· Citations to the Article (22) (Citation History)
· Refereed Citations to the Article
· SIMBAD Objects (6)
· NED Objects (2)
· Also-Read Articles (Reads History)
·
· Translate This Page
Title:
Photometric Recovery of Crowded Stellar Fields Observed with HST/WFPC2 and the Effects of Confusion Noise on the Extragalactic Distance Scale
Authors:
Ferrarese, Laura; Silbermann, N. A.; Mould, Jeremy R.; Stetson, Peter B.; Saha, Abhijit; Freedman, Wendy L.; Kennicutt, Robert C., Jr.
Affiliation:
AA(University of California, Los Angeles, CA 90095-1562 ), AB(Infrared Processing and Analysis Center, California Institute of Technology, Pasadena, CA 91125; ), AC(Research School of Astronomy and Astrophysics, Institute of Advanced Studies, Australian National University, ACT 2611, Australia; ), AD(Dominion Astrophysical Observatory, Victoria, BC V8X 4M6, Canada; ), AE(Kitt Peak National Observatory, NOAO, Tucson, AZ 85726; ), AF(Observatories of the Carnegie Institution of Washington, Pasadena, CA 91101; ), AG(Steward Observatory, University of Arizona, Tucson, AZ 85721; )
Publication:
The Publications of the Astronomical Society of the Pacific, Volume 112, Issue 768, pp. 177-201. (PASP Homepage)
Publication Date:
02/2000
Origin:
UCP
PASP Keywords:
COSMOLOGY: DISTANCE SCALE, GALAXIES: DISTANCES AND REDSHIFTS, GALAXIES: PHOTOMETRY, TECHNIQUES: PHOTOMETRIC
DOI:
10.1086/316520
Bibliographic Code:
2000PASP..112..177F

Abstract

We explore the limits of photometric reductions of crowded stellar fields observed with the Wide Field and Planetary Camera 2 on board the Hubble Space Telescope. Two photometric procedures, based on the DoPHOT and DAOPHOT/ALLFRAME programs, are tested, and the effects of crowding, complex sky background, and cosmic-ray contamination are discussed using an extensive set of artificial star simulations. As a specific application of the results presented in this paper, we assess the magnitude of photometric biases on programs aimed at finding Cepheids and determining distances. We find that while the photometry in individual images can be biased too bright by up to 0.2 mag in the most crowded fields due to confusion noise, the effects on distance measurements based on Cepheid variables are insignificant, less than 0.02 mag (1% in distance) even in the most problematic cases. This result, which is at odds with claims that have recently surfaced in the literature, is due to the strict criteria applied in the selection of the variable stars, and the photometric cross-checks made possible by the availability of multiple exposures in different filters which characterize Cepheid observations.
Bibtex entry for this abstract   Preferred format for this abstract (see Preferences)

   

Find Similar Abstracts:

Use: Authors
Title
Keywords (in text query field)
Abstract Text
Return: Query Results Return    items starting with number
Query Form
Database: Astronomy
Physics
arXiv e-prints