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Group Catalogues for 2dFGRS & SDSS
SDSS_DR7 available now.
DESI image legacy surveys DR8 group/cluster catalogs also available
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Group Catalogues for 2dFGRS & SDSS SDSS_DR7 available now. DESI image legacy surveys DR8 group/cluster catalogs also available
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Introduction Recently, we (Yang et al. 2005a) developed a halo-based group finder that is optimized for grouping galaxies that reside in the same dark matter halo. We tested the performance of this group finder extensively using mock galaxy redshift surveys constructed from the conditional luminosity function model (Yang, Mo, van den Bosch 2003; van den Bosch, Yang, Mo 2003; Yang et al. 2004), and found that our group finder is more successful than the conventional friends-of-friends (FOF) algorithm in associating galaxies according to their common dark matter haloes. In particular, our group finder performs also reliably for very poor systems, including isolated galaxies in small mass haloes. Using this group finder, we generated the group catalogues for both 2dFGRS and SDSS observations (Yang et al. 2005a, Weinmann et al. 2005) . These halo-based group catalogues allow us to probe the Halo-Occupation-Distribution in various aspects (Yang et al. 2005b,c,d; van den Bosch et al. 2005). Observations: 2dFGRS and SDSS Shown in the left panels are projected galaxy distributions in sliced regions in the 2dFGRS observation (upper) and in terms of sky coverage in the SDSS observation (lower).
SDSS DR4 Shown in the left panel is the projected galaxy distribution in terms of sky coverage in the SDSS DR4. Note that we have three versions of galaxy groups: with and without fiber collision corrections. Readers who are interested in this catalogue please check Yang et al. 2007 for the details of the construction of the group catalogue.
SDSS DR7 In this version, we have two sets of group catalogues: one based on the Petro magnitude and the other based on the model magnitude. The resulting group catalogues are named as petro? and model? (?=A,B,C), respectively. (Listed in the following table are numbers for model? groups). Shown in the left panel is the projected galaxy distribution in terms of sky coverage in the SDSS DR7. Similar to the DR4, we have three versions of galaxy groups: with and without fiber collision corrections. Readers who are interested in this catalogue please check Yang et al. 2007 for the details of the construction of the group catalogue.
References Galaxy Groups in the SDSS DR4. I. The Catalogue and Basic Properties Galaxy Groups in
the SDSS DR4. II. Halo Occupation Statistics Galaxy Groups in
the SDSS DR4: III. the luminosity and stellar mass functions Evolution of the Galaxy-Dark Matter Connection and the Assembly
of Galaxies in Dark Matter Halos
2MRS Group Catalog In this version, a galaxy group catalog is constructed from the 2MASS Redshift Survey (2MRS), which is complete to a limiting magnitude of K_s = 11.75, and covers about 91% of the full sky. The application of the halo-based group finder to the 2MRS gives 29,904 groups at z~0.08. Shown below is the distribution of 2MRS groups in galactic coordinates. Red, green and blue points represent groups within the redshift range: 0 < z < 0.02, 0.02 < z < 0.03 and 0.03 < z < 0.08, respectively.
References A Halo-Based Galaxy Group Finder: Calibration and Application to the 2dFGRS The Two-Point Correlation Functions of Galaxy Groups: Probing the Clustering of Dark Matter Halos Yang X., Mo H.J., Jing Y.P., van den Bosch F.C., 2005c, MNRAS, 358, 217 Galaxy Groups in the SDSS DR4. I. The Catalogue and Basic Properties Galaxy groups in the 2MASS Redshift Survey
Low Redshift Group Catalog Here we provide the group catalogs (along with the galaxy catalogs they are based on) constructed by applying the group finder presented in Lim et al. (2017, submitted to MNRAS), which is largely based on the group finder of Yang et al. (2005, 2007) and Lu et al. (2016) but with a more uniform and improved halo assignment over a wider range of halo mass, to the four large redshift survey catalogs: 2MASS Redshift Survey (2MRS; Huchra et al. 2012), 6dF Galaxy Survey Data Release 3 (6dFGS; Jones et al. 2009), Sloan Digital Sky Survey Data Release 13 (SDSS DR13; Albareti et al. 2016), 2dF Galaxy Redshift Survey (2dFGRS; Colless et al. 2001). The figure shows the distribution of the groups constructed in galactic coordinates.
References A Halo-Based Galaxy Group Finder: Calibration and Application to the 2dFGRS Galaxy Groups in the SDSS DR4. I. The Catalogue and Basic Properties Galaxy groups in the 2MASS Redshift Survey Galaxy groups in the low-redshift Universe
Real Space Galaxy Catalogue We use a method to correct for the redshift-space distortions, and map the real space galaxy distribution. Based on the SDSS DR7 sample, we construct a real space version of main galaxy catalog, which contains 396068 galaxies within the redshift range 0.01 < z < 0.12 in the North Galactic Cap. Shown below is the galaxies distribution in the redshift space and the reconstruct real space in sliced regions. Note how the Sloan Great Wall is far less pronounced in real space than in redshift space.
References Mapping the real space distributions of galaxies in SDSS DR7: I. Two Point Correlation Functions
SDSS_MTV Shown in the below plot is the distribution of galaxies (upper left panel), groups (upper right panel), velocity field (lower left panel) and mass density field (lower right panel) extracted from the SDSS DR7 around the Great Wall (at z~0.08). Here, the data for the Mass, Tidal and Velocity fields (SDSS_MTV) are provided (See Wang et al. 2011 for details of the construction).
References Galaxy Groups in the SDSS DR4. I. The Catalogue and Basic Properties Reconstructing the cosmic density field with the distribution of
dark matter haloes Reconstructing the Cosmic Velocity and Tidal Fields with Galaxy
Groups Selected from the Sloan Digital Sky Survey
SDSS-RASS X-ray clusters Shown below is the distribution of 817 X-ray clusters (red dots) with S/N>3.0 detections, plotted on top of the SDSS DR7 sky coverage (black region). Here, we made use of ROSAT All Sky Survey (RASS) broadband X-ray images and the optical clusters identified from SDSS DR7 to estimate the X-ray luminosities around ~65,000 candidate clusters with masses >1013 based on an Optical to X-ray (OTX) code we develop. (See Wang et al. 2013 for details of the construction).
References Galaxy Groups in the SDSS DR4. I. The Catalogue and Basic Properties Measuring the X-ray luminosities of SDSS DR7 clusters from ROSAT All Sky Survey
Mock 2dFGRS Group Catalogues Before download the group catalogues, you need to download the mock 2dFGRS catalogues.
References A Halo-Based Galaxy Group Finder: Calibration and Application to the 2dFGRS The Two-Point Correlation Functions of Galaxy Groups: Probing the Clustering of Dark Matter Halos Yang X., Mo H.J., Jing Y.P., van den Bosch F.C., 2005c, MNRAS, 358, 217 The Phase-Space Parameters of Brightest Halo Galaxies van den Bosch F.C. Weinmann S. M., Yang X., Mo H.J., Li C., Jing Y.P., 2005, MNRAS, 361, 1203 The Cross-Correlation between Galaxies and Groups: Probing the Galaxy Distribution in and around Dark Matter Haloes Comments to:
xyang@sjtu.edu.cn |
