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The Planetary Nebula Luminosity Function in the Era of Precision Cosmology
Frontiers in Astronomy and Space Sciences, 2022 One of the great surprises of the late 1980s was the discovery that the [O III] λ5007 planetary nebula luminosity function (PNLF) could be used as a precision extragalactic standard candle.
Robin Ciardullo, Robin Ciardullo
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The Extragalactic Distance Scale [PDF]
Publications of the Astronomical Society of the Pacific, 1960 22 pages, Postscript, no figures.
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HI Linewidths, Rotation Velocities and the Tully-Fisher Relation [PDF]
Journal of Astronomy and Space Sciences, 2005 We determine the rotation velocities of 108 spiral and irregular galaxies (XV-Sample) from first-order rotation curves from position-velocity maps, based on short 21-cm observations with the Westerbork Synthesis Radio Telescope (WSRT).
Myung-Hyun Rhee, Adrick H. Broeils
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Modeling large-scale dispersal distances [PDF]
Ecological Modelling, 2002 Abstract We present an approach to analyze dispersal distance data. This approach allows one to take into account accuracy of the recorded dispersal distances. Three distributions were used, all assuming continuous space; a maximum likelihood approach was used for parameter estimation and model selection.
Paradis, Emmanuel +2 more
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The Open Journal of Astrophysics, 2020 The Universe is not completely homogeneous. Even if it is sufficiently so on large scales, it is very inhomogeneous at small scales, and this has an effect on light propagation, so that the distance as a function of redshift, which in many cases is ...
Phillip Helbig
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INSIGHTS INTO THE CEPHEID DISTANCE SCALE [PDF]
The Astrophysical Journal, 2010 We present an investigation of Cepheid distances using theory and observations. Cepheid models indicate that the slope of the Period-Luminosity (P-L) relation covering the entire period range (0.40<= logP <=2.0) becomes steeper when moving from optical to NIR bands, and that the metallicity dependence of the slope decreases from the B- to the K ...
BONO, GIUSEPPE +3 more
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Guttman Scale Analysis of the Distance Vision Scale [PDF]
Investigative Opthalmology & Visual Science, 2009 The Distance Vision Scale (DVS) is a self-assessment of visual acuity (VA). Like VA testing in which letter reading becomes progressively difficult through the test, DVS questions have a hierarchy of difficulty (Guttman scale). The aims were to determine whether the DVS fulfills Guttman scaling criteria and to test the relationship between DVS score ...
Pesudovs, Konrad +3 more
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SNe Ia Redshift in a Nonadiabatic Universe
Universe, 2018 By relaxing the constraint of adiabatic universe used in most cosmological models, we have shown that the new approach provides a better fit to the supernovae Ia redshift data with a single parameter, the Hubble constant H0, than the standard ΛCDM
Rajendra P. Gupta
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The galactic distance scale [PDF]
Symposium - International Astronomical Union, 1979 Recent work on the distance scale of the Galaxy has largely been in the direction of refining previously established methods. The RR Lyrae variable stars appear to be better distance indicators than was once thought and they have been used in determining Ro, the distance to the Galactic center.
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Perturbation and scaled Cook’s distance
The Annals of Statistics, 2012 Cook's (Cook, 1977) distance is one of the most important diagnostic tools for detecting influential individual or subsets of observations in linear regression for cross-sectional data. However, for many complex data structures (e.g., longitudinal data), no rigorous approach has been developed to address a fundamental issue: deleting subsets with ...
Zhu, Hongtu +2 more
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