The extragalactic Cepheid distance bias: Numerical simulations
نویسندگان
چکیده
منابع مشابه
Has Blending Compromised Cepheid-based Determinations of the Extragalactic Distance Scale?
We examine the suggestion that half of the galaxies observed by the Hubble Space Telescope Key Project and the Type Ia Supernova Calibration Team have had their distances systematically underestimated, by 0.1-0.3 mag in the distance modulus, because of the underappreciated influence of stellar profile blending on the Wide Field Camera chips. The signature of such an effect would be a systematic...
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Significant progress has been made during the last 10 years toward resolving the debate over the expansion rate of the Universe. The current value of the Hubble parameter, H 0, is now arguably known with an accuracy of 10%, largely due to the tremendous increase in the number of galaxies in which Cepheid variable stars have been discovered. Increasingly accurate secondary distance indicators, m...
متن کاملThe Extragalactic Distance Database
A database can be accessed on the web at http://edd.ifa.hawaii.edu that was developed to promote access to information related to galaxy distances. The database has three functional components. First, tables from many literature sources have been gathered and enhanced with links through a distinct galaxy naming convention. Second, comparisons of results both at the levels of parameters and of t...
متن کاملThe Extragalactic Distance Scale
Cepheid variables are used to derive a Virgo cluster distance of 16.0 ± 1.5 Mpc. In conjunction with the Coma velocity and the well-established Coma/Virgo distance ratio, this yields a Hubble parameter H = 81 ± 8 km s o-1 Mpc. By combining this value with an age of the Universe / 16.8 ± 2.1 Gyr, that-1 is derived from the metal-poor globular cluster M92, one obtains f (5, %) / 1.39 ± 0.22. This...
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If a Cepheid luminosity at given period depends on metallicity, then the P-L relation in galaxies with higher metallicities may show a higher dispersion if these galaxies also sample a wider range of intrinsic metallicities. Using published HST Cepheid data from 25 galaxies, we have found such a correlation between the the P-L dispersion and host galaxy metallicity which is significant at the ≈...
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ژورنال
عنوان ژورنال: Astronomy & Astrophysics
سال: 2004
ISSN: 0004-6361,1432-0746
DOI: 10.1051/0004-6361:20031698