Non-detection of a statistically anisotropic power spectrum in large-scale structure

Anthony R. Pullen, Christopher M. Hirata

    Research output: Contribution to journalArticlepeer-review


    We search a sample of photometric luminous red galaxies (LRGs) measured by the Sloan Digital Sky Survey (SDSS) for a quadrupolar anisotropy in the primordial power spectrum, in which P() is an isotropic power spectrum (k) multiplied by a quadrupolar modulation pattern. We first place limits on the 5 coefficients of a general quadrupole anisotropy. We also consider axisymmetric quadrupoles of the form P() = (k)1+g*[()2-(1/3)] where is the axis of the anisotropy. When we force the symmetry axis to be in the direction (l,b) = (94°,26°) identified in the recent Groeneboom et al. analysis of the cosmic microwave background, we find g* = 0.0060.036 (1σ). With uniform priors on and g* we find that -0.41 < g* < +0.38 with 95% probability, with the wide range due mainly to the large uncertainty of asymmetries aligned with the Galactic Plane. In none of these three analyses do we detect evidence for quadrupolar power anisotropy in large scale structure.

    Original languageEnglish (US)
    Article number027
    JournalJournal of Cosmology and Astroparticle Physics
    Issue number5
    StatePublished - 2010


    • Galaxy surveys
    • Power spectrum

    ASJC Scopus subject areas

    • Astronomy and Astrophysics


    Dive into the research topics of 'Non-detection of a statistically anisotropic power spectrum in large-scale structure'. Together they form a unique fingerprint.

    Cite this