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Published in "The Extraglactic Distance Scale",
eds. M. Livio, M. Donahue and N. Panagia, Space Telescope Science
Institute Symposium Series 10, 1997
For a PDF version of the article, click
here.
We describe the method which measures surface brightness fluctuation (SBF) to determine galaxy distances. We have completed a survey of about 400 nearby galaxies, and basing our zero point on observations of Cepheid variable stars we find that the absolute SBF magnitude in the Kron-Cousins I band correlates well with the mean (V-I) color of a galaxy according to
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for 1.0 < (V - I) < 1.3. This agrees well with theoretical estimates from stellar population models.
Comparisons between SBF distances and a variety of other estimators,
including Cepheid
variable stars, the Planetary Nebula Luminosity Function (PNLF),
Tully-Fisher (TF), Dn -
,
SNII, and SNIa, indicate that the calibration of SBF is universally
valid and that SBF error
estimates are accurate. The zero point given by Cepheids, PNLF, TF (both
calibrated using
Cepheids), and SNII is in units of Mpc; the zero point given by TF
(referenced to a distant frame), Dn -
, and SNIa is in terms
of a Hubble expansion velocity expressed in km/s. Tying
together these two zero points yields a Hubble constant of
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As part of this analysis, we present SBF distances to 12 nearby groups of galaxies where Cepheids, SNII, and SNIa have been observed.
The results presented in this conference contribution will mostly be published soon in the ApJ (Tonry, Blakeslee, Ajhar, and Dressler 1997, TBAD97). Accordingly, there are few references to the literature, since they can be found in that source, along with all the details which are only treated very superficially here.
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