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arXiv · 0907.5457

The REFLEX galaxy cluster survey. VIII. Spectroscopic observations and optical atlas

L. Guzzo·P. Schuecker·H. Boehringer·C. A. Collins·A. Ortiz-Gil·S. De Grandi·A. C. Edge·D. M. Neumann·S. Schindler·C. Altucci·P. A. Shaver
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Abstract

We present the final data from the spectroscopic survey of the ROSAT-ESO Flux-Limited X-ray (REFLEX) catalog of galaxy clusters. The REFLEX survey covers 4.24 steradians (34% of the entire sky) below a declination of 2.5 deg and at high Galactic latitude (|b| > 20 deg). The REFLEX catalog includes 447 entries with a median redshift of 0.08 and is better than 90% complete to a limiting flux fx = 3x10^{-12} erg s^{-1} cm^{-2} (0.1 to 2.4 keV), representing the largest statistically homogeneous sample of clusters drawn from the ROSAT All-Sky Survey (RASS) to date. Here we describe the details of the spectroscopic observations carried out at the ESO 1.5 m, 2.2 m, and 3.6 m telescopes, as well as the data reduction and redshift measurement techniques. The spectra typically cover the wavelength range 3600-7500 A at a FWHM resolution of ~14 A, and the measured redshifts have a total rms error of ~100 km s^{-1}. In total we present 1406 new galaxy redshifts in 192 clusters, most of which previously did not have any redshift measured. Finally, the luminosity/redshift distributions of the cluster sample and a comparison to the no-evolution expectations from the cluster X-ray luminosity function are presented.

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L. Guzzo, P. Schuecker, H. Boehringer, C. A. Collins, A. Ortiz-Gil, S. De Grandi, A. C. Edge, D. M. Neumann, S. Schindler, C. Altucci, P. A. Shaver. 2009-07-31. The REFLEX galaxy cluster survey. VIII. Spectroscopic observations and optical atlas. https://doi.org/10.1051/0004-6361%2F200810838

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