Astronomy and Astrophysics – Astrophysics
Scientific paper
May 2010
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2010a%26a...514a.102t&link_type=abstract
Astronomy and Astrophysics, Volume 514, id.A102
Astronomy and Astrophysics
Astrophysics
23
Cosmology: Observations, Large-Scale Structure Of Universe, Galaxies: Clusters: General, Catalogs
Scientific paper
Aims: We extract groups of galaxies as flux-limited and volume-limited samples from the SDSS Data Release 7 (DR7) to study the supercluster-void network and environmental properties of groups therein. Volume-limited catalogues are particularly useful for a comparison of numerical simulations of dark matter halos and the large-scale structure with observations. Methods: The extraction of a volume-limited sample of galaxies and groups requires special care to avoid excluding too much observational data. We use a modified friends-of-friends (FoF) method with a slightly variable linking length to obtain a preliminary flux-limited sample. We take the flux-limited groups as the basic sample to include as many galaxies as possible in the volume-limited samples. To determine the scaling of the linking length we calibrated group sizes and mean galaxy number densities within groups by magnitude dilution of a nearby group sub-sample to follow the properties of groups with higher luminosity limits. Results: Our final flux-limited sample contains 78800 groups and volume-limited subsamples with absolute magnitude limits Mr = -18, -19, -20, and -21 contain 5463, 12 590, 18 973, and 9139 groups, respectively, in the DR7 main galaxy main area survey. The group catalogue is available at the CDS. Conclusions: The spatial number densities of our groups within the subsamples, as well as the mean sizes and rms velocities of our groups practically do not change from sub-sample to sub-sample. This means that the catalogues are homogeneous and well suited for a comparison with simulations.
Full Table 2 is only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/514/A102
Einasto Jaan
Einasto Maret
Heinämäki Pekka
Nurmi Pasi
Saar Enn
No associations
LandOfFree
Groups of galaxies in the SDSS Data Release 7 . Flux- and volume-limited samples does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Groups of galaxies in the SDSS Data Release 7 . Flux- and volume-limited samples, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Groups of galaxies in the SDSS Data Release 7 . Flux- and volume-limited samples will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1889570