Derivation of Distances with the Tully-Fisher Relation: The Antlia Cluster

N. Bonhomme; H. M. Courtois; R. B. Tully

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arXiv · 0806.1140

Derivation of Distances with the Tully-Fisher Relation: The Antlia Cluster

N. Bonhomme·H. M. Courtois·R. B. Tully

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Abstract

The Tully-Fisher relation is a correlation between the luminosity and the HI 21cm line width in spiral galaxies (LLW relation). It is used to derive galaxy distances in the interval 7 to 100 Mpc. Closer, the Cepheids, TRGB and Surface Brightness Fluctuation methods give a better accuracy. Further, the SNIa are luminous objects still available for distance measurement purposes, though with a dramatically lower density grid of measurements on the sky. Galaxies in clusters are all at the same distance from the observer. Thus the distance of the cluster derived from a large number of galaxies (N) has an error reduced according to the square root of N. However, not all galaxies in a cluster are suitable for the LLW measurement. The selection criteria we use are explained hereafter; the important point being to avoid Malmquist bias and to not introduce any systematics in the distance measurement.

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N. Bonhomme, H. M. Courtois, R. B. Tully. 2008-06-06. Derivation of Distances with the Tully-Fisher Relation: The Antlia Cluster. https://arxiv.org/abs/0806.1140

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