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Visiting Astronomer, German-Spanish Astronomical Center, Calar Alto, operated by the Max-Planck-Institut für Astronomie jointly with the Spanish National Commission for Astronomy.

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... NRAO

National Radio Astronomy Observatory.

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... VLA

Very Large Array, operated by the NRAO.

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... size

We assume that H₀=50 kms^-1Mpc^-1 and q₀=0.5.

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... IRAF

IRAF is the Image Reduction and Analysis Facility made available to the astronomical community by the National Optical Astronomy Observatories, which are operated by the Association of Universities for Research in Astronomy (AURA), Inc., under contract with the U.S. National Science Foundation.

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