{
  "id": "0905.3324",
  "version": "v2",
  "published": "2009-05-20T17:20:37.000Z",
  "updated": "2010-02-01T12:46:21.000Z",
  "title": "Too few spots in the cosmic microwave background",
  "authors": [
    "Youness Ayaita",
    "Maik Weber",
    "Christof Wetterich"
  ],
  "comment": "12 pages; changes in the abstract, extended discussion of the quadrupole and the significances, minor clarifications, one added figure (behavior of typical simulations), one added reference",
  "journal": "Phys.Rev.D81:023507,2010",
  "doi": "10.1103/PhysRevD.81.023507",
  "categories": [
    "astro-ph.CO"
  ],
  "abstract": "We investigate the abundance of large-scale hot and cold spots in the WMAP-5 temperature maps and find considerable discrepancies compared to Gaussian simulations based on the LCDM best-fit model. Too few spots are present in the reliably observed cosmic microwave background (CMB) region, i.e., outside the foreground-contaminated parts excluded by the KQ75 mask. Even simulated maps created from the original WMAP-5 estimated multipoles contain more spots than visible in the measured CMB maps. A strong suppression of the lowest multipoles would lead to better agreement. The lack of spots is reflected in a low mean temperature fluctuation on scales of several degrees (4 to 8), which is only shared by less than 1% (0.16%-0.62%) of Gaussian LCDM simulations. After removing the quadrupole, the probabilities change to 2.5%-8.0%. This shows the importance of the anomalously low quadrupole for the statistical significance of the missing spots. We also analyze a possible violation of Gaussianity or statistical isotropy (spots are distributed differently outside and inside the masked region).",
  "revisions": [
    {
      "version": "v2",
      "updated": "2010-02-01T12:46:21.000Z"
    }
  ],
  "analyses": {
    "subjects": [
      "98.70.Vc",
      "98.80.-k"
    ],
    "keywords": [
      "cosmic microwave background",
      "low mean temperature fluctuation",
      "gaussian lcdm simulations",
      "lcdm best-fit model",
      "temperature maps"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "publisher": "APS",
      "journal": "Physical Review D",
      "year": 2010,
      "month": "Jan",
      "volume": 81,
      "number": 2,
      "pages": "023507"
    },
    "note": {
      "typesetting": "TeX",
      "pages": 12,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 820934,
      "adsabs": "2010PhRvD..81b3507A"
    }
  }
}