期刊
ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES
卷 165, 期 1, 页码 108-137出版社
UNIV CHICAGO PRESS
DOI: 10.1086/503800
关键词
Cepheids; distance scale; galaxies : distances and redshifts; supernovae : general
With this paper we continue the preparation for a forthcoming summary report of our experiment with the HST to determine the Hubble constant using Type Ia supernovae as standard candles. Two problems are addressed. (1) We examine the need for, and determine the value of, the corrections to the apparent magnitudes of our program Cepheids in the 11 previous calibration papers due to sensitivity drifts and charge transfer effects of the HST WFPC2 camera over the life time of the experiment from 1992 to 2001. (2) The corrected apparent magnitudes are applied to all our previous photometric data from which revised distance moduli are calculated for the eight program galaxies that are parents to the calibrator Ia supernovae. Two different Cepheid P-L relations are used; one for the Galaxy and one for the LMC. These differ both in slope and zero point at a fixed period. The procedures for determining the absorption and reddening corrections for each Cepheid are discussed. Corrections for the effects of metallicity differences between the program galaxies and the two adopted P-L relations are derived and applied. The distance moduli derived here for the eight supernovae program galaxies, and for 29 others, average 0.20 mag fainter (more distant) than those derived by Gibson et al. and Freedman et al. in their 2000 and 2001 summary papers for reasons discussed in this paper. The effect on the Hubble constant is the subject of our forthcoming summary paper.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据