3 papers
astro-ph2002
Cepheid, Tully-Fisher and SNIa Distances
T. Shanks, P. D. Allen, F. Hoyle +1
We first discuss why the uncomfortable fine-tuning of the parameters of the Lambda-CDM cosmological model provides continuing, strong motivation to investigate Hubble's Constant. T…
astro-ph2001
Cepheid and SNIa Distance Scales
T. Shanks, P. D. Allen, F. Hoyle +1
We first discuss why there remains continuing, strong motivation to investigate Hubble's Constant. Then we review new evidence from an investigation of the Galactic Open Clusters c…
astro-ph2001
The Effects of Metallicity on the Cepheid P-L Relation and the Consequences for the Extragalactic Distance Scale
Paul D. Allen, Tom Shanks
Using published HST Cepheid data from 25 galaxies, we have found a correlation between the P-L dispersion and host galaxy metallicity which is significant at the ~3sigma level in t…