منابع مشابه
0 Local Distance Indicators
A summary is given of the calibration of the Cepheid scale required in the derivation of distances from observations at V and I, as in the HST work on extragalactic Cepheids. There is some evidence that a small metallicity correction may be necessary in deriving distances in this way. The evidence for this comes both from observations of Cepheids of different metallicities and from a comparison...
متن کاملAGB Variables as Distance Indicators
Evidence for the existence of Mira Period-Luminosity relations is reviewed including recent work on Miras with thick circumstellar shells. The calibration of the relation at K is discussed in detail. The nature of variables deviating from the PL relation and possible metallicity effects are also discussed.
متن کاملCosmological consequences of short distance physics
Inflation can act as a space-time microscope for Planck or string scale effects, leaving potentially observable traces in the primordial perturbation spectrum. I discuss two frameworks that were used recently to study this phenomenon: nonlinear dispersion and short distance uncertainty. To the best of our current understanding, inflation – an epoch of accelerated cosmological expansion – may ha...
متن کاملEnear Redshift-distance Survey: Cosmological Constraints
We present an analysis of the ENEAR sample of peculiar velocities of field and cluster elliptical galaxies, obtained with Dn–σ distances. We use the velocity correlation function, ψ1(r), to analyze the statistics of the field–object’s velocities, while the analysis of the cluster data is based on the estimate of their r.m.s. peculiar velocity, Vrms. The results are compared with predictions fro...
متن کاملCepheids as Distance Indicators: Some Current Problems
A general review is given of the calibration of the Cepheid distance scale, with particular reference to its use in the determination of H0. Emphasis is placed on the advantage of using a galactic calibration of the Cepheid scale, rather than relying on an adopted distance to the LMC. It is then possible to use LMC data to test for possible metallicity effects on this scale.
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: Space Science Reviews
سال: 2018
ISSN: 0038-6308,1572-9672
DOI: 10.1007/s11214-018-0524-3