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Seeking the Local Convergence Depth. I. TF Observations of the Clusters A168, A397, A569, A1139, A1228, and A1983

Daniel A. Dale·Riccardo Giovanelli·Martha P. Haynes·Marco Scodeggio·Eduardo Hardy·Luis E. Campusano
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Abstract

We present first results of an all-sky observing program designed to improve the quality of the I band Tully-Fisher (TF) template and to obtain the reflex motion of the Local Group with respect to clusters to z = 0.06. We are obtaining between 5 and 15 TF measurements per cluster on a sample of 50 clusters at intermediate redshifts (0.02 < z < 0.06). Presentation of the data for seven Abell clusters of galaxies is given here. This data incorporates methods for estimating the true inclination of a spiral disk, an observational parameter undervalued for small angular-sized galaxies or for galaxies observed in poor seeing conditions.

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Daniel A. Dale, Riccardo Giovanelli, Martha P. Haynes, Marco Scodeggio, Eduardo Hardy, Luis E. Campusano. 1997-05-11. Seeking the Local Convergence Depth. I. TF Observations of the Clusters A168, A397, A569, A1139, A1228, and A1983. https://doi.org/10.1086/118486

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