{
  "id": "0706.1314",
  "version": "v1",
  "published": "2007-06-10T13:59:11.000Z",
  "updated": "2007-06-10T13:59:11.000Z",
  "title": "When Did Cosmic Acceleration Start ?",
  "authors": [
    "Alessandro Melchiorri",
    "Luca Pagano",
    "Stefania Pandolfi"
  ],
  "comment": "5 pages, 2 figures",
  "journal": "Phys.Rev.D76:041301,2007",
  "doi": "10.1103/PhysRevD.76.041301",
  "categories": [
    "astro-ph",
    "gr-qc",
    "hep-ph"
  ],
  "abstract": "A precise determination, and comparison, of the epoch of the onset of cosmic acceleration, at redshift z_acc, and of dark energy domination, at z_eq, provides an interesting measure with which to parameterize dark energy models. By combining several cosmological datasets we place constraints on the redshift and age of cosmological acceleration. For a Lambda-CDM model, we find the constraint z_acc=0.76\\pm0.10 at 95% c.l., occurring 6.7\\pm0.4 Gyrs ago. Allowing a constant equation of state but different from -1 changes the constraints to z_acc=0.81\\pm0.12 (6.9\\pm0.5 Gyrs ago) and z_eq=0.48\\pm0.14(4.9\\pm0.9 Gyrs ago), while dynamical models markedly increase the error on the constraints with z_acc=0.81\\pm0.30 (6.8\\pm1.4 Gyrs ago) and z_eq=0.44\\pm0.20 (4.5\\pm1.0 Gyrs ago). Unified dark energy models as Silent Quartessence yield: z_acc=0.80\\pm0.16 (6.8\\pm0.6 Gyrs ago).",
  "revisions": [
    {
      "version": "v1",
      "updated": "2007-06-10T13:59:11.000Z"
    }
  ],
  "analyses": {
    "subjects": [
      "95.36.+x"
    ],
    "keywords": [
      "cosmic acceleration start",
      "constraint",
      "dark energy domination",
      "parameterize dark energy models",
      "unified dark energy models"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "publisher": "APS",
      "journal": "Physical Review D",
      "year": 2007,
      "month": "Aug",
      "volume": 76,
      "number": 4,
      "pages": "041301"
    },
    "note": {
      "typesetting": "TeX",
      "pages": 5,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 752771,
      "adsabs": "2007PhRvD..76d1301M"
    }
  }
}