Two-dimensional topology of the sloan digital sky survey

Fiona Hoyle, Michael S. Vogeley, J. Richard Gott, Michael Blanton, Max Tegmark, David H. Weinberg, N. Bahcall, J. Brinkmann, D. York

    Research output: Contribution to journalArticle

    Abstract

    We present the topology of a volume-limited sample of 11,884 galaxies, selected from an apparent magnitude limited sample of over 100,000 galaxies observed as part of the Sloan Digital Sky Survey (SDSS). The data currently cover three main regions on the sky: one in the Galactic north and one in the south, both at zero degrees declination, and one area in the north at higher declination. Each of these areas covers a wide range of survey longitude but a narrow range of survey latitude, allowing the two-dimensional genus to be measured. The genus curves of the SDSS subsamples are similar, after appropriately normalizing these measurements for the different areas. We sum the genus curves from the three areas to obtain the total genus curve of the SDSS. The total curve has a shape similar to the genus curve derived from mock catalogs drawn from the Hubble volume ACDM simulation and is similar to that of a Gaussian random field. Likewise, comparison with the genus of the Two-Degree Field Galaxy Redshift Survey, after normalization for the difference in area, reveals remarkable similarity in the topology of these samples. We test for the effects of galaxy-type segregation by splitting the SDSS data into thirds, based on the u*-r* colors of the galaxies, and measure the genus of the reddest and bluest subsamples. This red/blue split in u*-r* is essentially a split by morphology, as explained by Strateva and coworkers. We find that the genus curve for the reddest galaxies exhibits a "meatball" shift of the topology - reflecting the concentration of red galaxies in high-density regions - compared to the bluest galaxies and the full sample, in agreement with predictions from simulations.

    Original languageEnglish (US)
    Pages (from-to)663-671
    Number of pages9
    JournalAstrophysical Journal
    Volume580
    Issue number2 I
    DOIs
    StatePublished - Dec 1 2002

    Fingerprint

    topology
    galaxies
    curves
    declination
    normalizing
    longitude
    simulation
    catalogs
    sky
    color
    prediction
    shift
    predictions

    Keywords

    • Cosmology: observations
    • Galaxies: distances and redshifts
    • Large-scale structure of universe
    • Methods: statistical

    ASJC Scopus subject areas

    • Space and Planetary Science

    Cite this

    Hoyle, F., Vogeley, M. S., Gott, J. R., Blanton, M., Tegmark, M., Weinberg, D. H., ... York, D. (2002). Two-dimensional topology of the sloan digital sky survey. Astrophysical Journal, 580(2 I), 663-671. https://doi.org/10.1086/343734

    Two-dimensional topology of the sloan digital sky survey. / Hoyle, Fiona; Vogeley, Michael S.; Gott, J. Richard; Blanton, Michael; Tegmark, Max; Weinberg, David H.; Bahcall, N.; Brinkmann, J.; York, D.

    In: Astrophysical Journal, Vol. 580, No. 2 I, 01.12.2002, p. 663-671.

    Research output: Contribution to journalArticle

    Hoyle, F, Vogeley, MS, Gott, JR, Blanton, M, Tegmark, M, Weinberg, DH, Bahcall, N, Brinkmann, J & York, D 2002, 'Two-dimensional topology of the sloan digital sky survey', Astrophysical Journal, vol. 580, no. 2 I, pp. 663-671. https://doi.org/10.1086/343734
    Hoyle F, Vogeley MS, Gott JR, Blanton M, Tegmark M, Weinberg DH et al. Two-dimensional topology of the sloan digital sky survey. Astrophysical Journal. 2002 Dec 1;580(2 I):663-671. https://doi.org/10.1086/343734
    Hoyle, Fiona ; Vogeley, Michael S. ; Gott, J. Richard ; Blanton, Michael ; Tegmark, Max ; Weinberg, David H. ; Bahcall, N. ; Brinkmann, J. ; York, D. / Two-dimensional topology of the sloan digital sky survey. In: Astrophysical Journal. 2002 ; Vol. 580, No. 2 I. pp. 663-671.
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    AU - Tegmark, Max

    AU - Weinberg, David H.

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