2MASS Redshift Survey (2MRS) Catalog

This table is based on the results of the 2MASS Redshift Survey (2MRS), a ten-year project to map the full three-dimensional distribution of galaxies in the nearby universe. The Two Micron All Sky Survey (2MASS) was completed in 2003 and its final data products, including an extended source catalog (XSC), are available online. The 2MASS XSC contains nearly a million galaxies with K&lt;sub&gt;s&lt;/sub&gt; &lt;= 13.5 mag and is essentially complete and mostly unaffected by interstellar extinction and stellar confusion down to a galactic latitude of |b| = 5 degrees for bright galaxies. Near-infrared wavelengths are sensitive to the old stellar populations that dominate galaxy masses, making 2MASS an excellent starting point to study the distribution of matter in the nearby universe. The authors selected a sample of 44,599 2MASS galaxies with K&lt;sub&gt;s&lt;/sub&gt; &lt;= 11.75 mag and |b| &gt;= 5 degrees (&gt;= 8 degrees toward the Galactic bulge) as the input catalog for their survey. They obtained spectroscopic observations for 11,000 galaxies and used previously obtained velocities for the remainder of the sample to generate a redshift catalog that is 97.6% complete to well-defined limits and covers 91% of the sky. This provides an unprecedented census of galaxy (baryonic mass) concentrations within 300 Mpc. Earlier versions of their survey have been used in a number of publications that have studied the bulk motion of the Local Group, mapped the density and peculiar velocity fields out to 50 h&lt;sup&gt;-1&lt;/sup&gt; Mpc, detected galaxy groups, and estimated the values of several cosmological parameters. Additionally, the authors present morphological types for a nearly complete sub-sample of 20,860 galaxies with K&lt;sub&gt;s&lt;/sub&gt; &lt;= 11.25 mag and |b| &gt;= 10 degrees. The authors initially selected 45,086 sources which met the following criteria: &lt;pre&gt; K&lt;sub&gt;s&lt;/sub&gt; &lt;= 11.75 mag and detected at H, E(B - V) &lt;= 1 mag, |b| &gt;= 5 degrees for 30 degrees &lt; l &lt; 330 degrees, |b| &gt;= 8 degrees otherwise. &lt;/pre&gt; They rejected 324 sources of galactic origin (multiple stars, planetary nebulae, and H II regions) or pieces of galaxies detected as separate sources by the 2MASS pipeline. Additionally, they flagged 314 bona fide galaxies with compromised photometry for reprocessing at a future date. Some of these galaxies have bright stars very close to their nuclei which were not detected by the pipeline. Others are in regions of high stellar density and their center positions and/or isophotal radii have been incorrectly measured by the pipeline. Lastly, some are close pairs or multiples but the pipeline only identified a single object. A detailed explanation of the steps taken to reject and reprocess the flagged galaxies is given in the Appendix of the reference paper. In summary, the final input catalog contained here has 44,599 entries (plotted using black symbols in Figure 1 of the reference paper). In this table, redshifts for 43,533 of the selected galaxies, or 97.6% of the sample, are presented. This table was created by the HEASARC in April 2012 based on an electronic version of Table 3 of the reference paper which was obtained from the ApJS website. This is a service provided by NASA HEASARC .

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Organization: National Aeronautics and Space Administration