Evidence for the extragalactic Cepheid distance bias from the kinematical distance scale
نویسندگان
چکیده
منابع مشابه
The 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...
متن کاملThe Extragalactic Distance Scale
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 کاملHipparcos Parallaxes and the Cepheid Distance Scale
Hipparcos parallaxes have recently become available for a sample of Galactic Cepheids, and we have used these new distances to calibrate the Cepheid periodluminosity (PL) relation at six wavelengths (BV IJHK). Comparing these calibrations with previously published multiwavelength PL relations we find agreement to within 0.07 ± 0.14 mag, or 4 ±7% in distance. Unfortunately, the current parallax ...
متن کاملThe Extragalactic Distance Scale without Cepheids
Distances of galaxies in the Hubble Space Telescope Key Project are based on the Cepheid period-luminosity relation. An alternative basis is the tip of the red giant branch. Using archival HST data, we calibrate the infrared TullyFisher relation using 14 galaxies with tip of the red giant branch measurements. Compared with the Key Project, a higher value of the Hubble Constant by 10% ± 7% is in...
متن کاملHas 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...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Astronomy & Astrophysics
سال: 2002
ISSN: 0004-6361,1432-0746
DOI: 10.1051/0004-6361:20011630