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The LCO/Palomar 10,000 km/sec Cluster Survey

Jeffrey A. Willick
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Abstract

I describe a Tully-Fisher (TF) survey of galaxies in 15 Abell Clusters distributed around the sky in the redshift range 9000-13,000 km/sec. The observations were done between 1992 and 1995 at the Las Campanas (LCO) and Palomar Observatories. The program is known as the LP10K survey. The basic data set consists of R band CCD magnitudes and H-alpha rotation curves for over 200 spiral galaxies. The TF relation is found to have a mild but statistically significant surface brightness dependence, v_{TF} ~ L^{0.28} I_e^{0.13}, and the intrinsic TF scatter is found to be 0.28 +/- 0.07 mag. A maximum-likelihood method is applied to the LP10K data set to test for large-scale bulk streaming. A formal result of v_B=720 +/- 300 km/sec is found. However, this finding is in disagreement with several results on smaller scales, including the Shellflow result reported at the Cosmic Flows conference, which indicate convergence to the CMB frame by ~ 6000 km/sec redshift.

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Jeffrey A. Willick. 1999-09-01. The LCO/Palomar 10,000 km/sec Cluster Survey. https://arxiv.org/abs/astro-ph/9909004

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