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Title: Cosmological data and indications for new physics

Data from the Atacama Cosmology Telescope (ACT) and the South Pole Telescope (SPT), combined with the nine-year data release from the WMAP satellite, provide very precise measurements of the cosmic microwave background (CMB) angular anisotropies down to very small angular scales. Augmented with measurements from Baryonic Acoustic Oscillations surveys and determinations of the Hubble constant, we investigate whether there are indications for new physics beyond a Harrison-Zel'dovich model for primordial perturbations and the standard number of relativistic degrees of freedom at primordial recombination. All combinations of datasets point to physics beyond the minimal Harrison-Zel'dovich model in the form of either a scalar spectral index different from unity or additional relativistic degrees of freedom at recombination (e.g., additional light neutrinos). Beyond that, the extended datasets including either ACT or SPT provide very different indications: while the extended-ACT (eACT) dataset is perfectly consistent with the predictions of standard slow-roll inflation, the extended-SPT (eSPT) dataset prefers a non-power-law scalar spectral index with a very large variation with scale of the spectral index. Both eACT and eSPT favor additional light degrees of freedom on top of the Harrison-Zel'dovich model. eACT is consistent with zero neutrino masses, while eSPT favors nonzero neutrino masses at moremore » than 95% confidence.« less
Authors:
 [1] ; ; ;  [2] ;  [3] ;  [4] ;  [5] ;  [6]
  1. Physics Department and ICRA, Università di Roma ''La Sapienza'', Ple. Aldo Moro 2, 00185, Rome (Italy)
  2. Physics Department and INFN, Università di Roma ''La Sapienza'', Ple Aldo Moro 2, 00185, Rome (Italy)
  3. Department of Physics, University at Buffalo, the State University of New York, Buffalo, NY 14260-1500 (United States)
  4. Department of Astronomy and Astrophysics, Enrico Fermi Institute, and Kavli Institute for Cosmological Physics, University of Chicago, Chicago, Illinois 60637-1433 (United States)
  5. Dipartimento di Fisica e Science della Terra, Università di Ferrara and INFN, sezione di Ferrara, Polo Scientifico e Tecnologico - Edificio C Via Saragat, 1, I-44122 Ferrara Italy (Italy)
  6. Department of Theoretical Physics and Center for Astroparticle Physics (CAP) 24 quai E. Ansermet, CH-1211 Geneva 4 (Switzerland)
Publication Date:
OSTI Identifier:
22282624
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2013; Journal Issue: 10; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ANISOTROPY; BARYONS; COSMOLOGY; DEGREES OF FREEDOM; INFLATIONARY UNIVERSE; INFLATONS; MASS; NEUTRINOS; OSCILLATIONS; PERTURBATION THEORY; RECOMBINATION; RELATIVISTIC RANGE; RELICT RADIATION; SCALARS; TELESCOPES; VISIBLE RADIATION