|   | 
Details
   web
Records
Author Pandolfi, S.; Cooray, A.; Giusarma, E.; Kolb, E.W.; Melchiorri, A.; Mena, O.; Serra, P.
Title Harrison-Zel'dovich primordial spectrum is consistent with observations Type Journal Article
Year 2010 Publication (up) Physical Review D Abbreviated Journal Phys. Rev. D
Volume 81 Issue 12 Pages 123509 - 6pp
Keywords
Abstract Inflation predicts primordial scalar perturbations with a nearly scale-invariant spectrum and a spectral index approximately unity [the Harrison-Zel'dovich (HZ) spectrum]. The first important step for inflationary cosmology is to check the consistency of the HZ primordial spectrum with current observations. Recent analyses have claimed that a HZ primordial spectrum is excluded at more than 99% c. l. Here we show that the HZ spectrum is only marginally disfavored if one considers a more general reionization scenario. Data from the Planck mission will settle the issue.
Address [Pandolfi, Stefania] Univ Roma La Sapienza, ICRA, I-00185 Rome, Italy
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes ISI:000278555900003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 426
Permanent link to this record
 

 
Author Martinelli, M.; Lopez Honorez, L.; Melchiorri, A.; Mena, O.
Title Future CMB cosmological constraints in a dark coupled universe Type Journal Article
Year 2010 Publication (up) Physical Review D Abbreviated Journal Phys. Rev. D
Volume 81 Issue 10 Pages 103534 - 7pp
Keywords
Abstract Cosmic microwave background satellite missions as the ongoing Planck experiment are expected to provide the strongest constraints on a wide set of cosmological parameters. Those constraints, however, could be weakened when the assumption of a cosmological constant as the dark energy component is removed. Here we show that it will indeed be the case when there exists a coupling among the dark energy and the dark matter fluids. In particular, the expected errors on key parameters as the cold dark matter density and the angular diameter distance at decoupling are significantly larger when a dark coupling is introduced. We show that it will be the case also for future satellite missions as EPIC, unless CMB lensing extraction is performed.
Address [Martinelli, Matteo; Melchiorri, Alessandro] Univ Roma La Sapienza, Dept Phys, I-00185 Rome, Italy
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes ISI:000278146700047 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 429
Permanent link to this record
 

 
Author Calabrese, E.; de Putter, R.; Huterer, D.; Linder, E.V.; Melchiorri, A.
Title Future CMB constraints on early, cold, or stressed dark energy Type Journal Article
Year 2011 Publication (up) Physical Review D Abbreviated Journal Phys. Rev. D
Volume 83 Issue 2 Pages 023011 - 11pp
Keywords
Abstract We investigate future constraints on early dark energy (EDE) achievable by the Planck and CMBPol experiments, including cosmic microwave background (CMB) lensing. For the dark energy, we include the possibility of clustering through a sound speed c(s)(2) < 1 (cold dark energy) and anisotropic stresses parametrized with a viscosity parameter c(vis)(2). We discuss the degeneracies between cosmological parameters and EDE parameters. In particular we show that the presence of anisotropic stresses in EDE models can substantially undermine the determination of the EDE sound speed parameter c(s)(2). The constraints on EDE primordial energy density are however unaffected. We also calculate the future CMB constraints on neutrino masses and find that they are weakened by a factor of 2 when allowing for the presence of EDE, and highly biased if it is incorrectly ignored.
Address [Calabrese, Erminia; Melchiorri, Alessandro] Univ Roma La Sapienza, Dept Phys, I-00185 Rome, Italy
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes ISI:000286803300002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 563
Permanent link to this record
 

 
Author Giusarma, E.; Corsi, M.; Archidiacono, M.; de Putter, R.; Melchiorri, A.; Mena, O.; Pandolfi, S.
Title Constraints on massive sterile neutrino species from current and future cosmological data Type Journal Article
Year 2011 Publication (up) Physical Review D Abbreviated Journal Phys. Rev. D
Volume 83 Issue 11 Pages 115023 - 10pp
Keywords
Abstract Sterile massive neutrinos are a natural extension of the standard model of elementary particles. The energy density of the extra sterile massive states affects cosmological measurements in an analogous way to that of active neutrino species. We perform here an analysis of current cosmological data and derive bounds on the masses of the active and the sterile neutrino states, as well as on the number of sterile states. The so-called (3 + 2) models, with three sub-eV active massive neutrinos plus two sub-eV massive sterile species, is well within the 95% CL allowed regions when considering cosmological data only. If the two extra sterile states have thermal abundances at decoupling, big bang nucleosynthesis bounds compromise the viability of (3 + 2) models. Forecasts from future cosmological data on the active and sterile neutrino parameters are also presented. Independent measurements of the neutrino mass from tritium beta-decay experiments and of the Hubble constant could shed light on sub-eV massive sterile neutrino scenarios.
Address [Giusarma, Elena; de Putter, Roland; Mena, Olga] Univ Valencia, CSIC, IFIC, Valencia 46071, Spain
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes ISI:000292039800003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 660
Permanent link to this record
 

 
Author De Bernardis, F.; Martinelli, M.; Melchiorri, A.; Mena, O.; Cooray, A.
Title Future weak lensing constraints in a dark coupled universe Type Journal Article
Year 2011 Publication (up) Physical Review D Abbreviated Journal Phys. Rev. D
Volume 84 Issue 2 Pages 023504 - 10pp
Keywords
Abstract Probing the dark matter clustering and its evolution with weak lensing surveys constitutes a unique tool to constrain interacting dark energy models. We focus here on weak lensing forecasts from future Euclid and LSST-like surveys combined with the expected results from the ongoing Planck cosmic microwave background satellite experiment. We find that these future data could constrain the dimensionless coupling between dark matter and dark energy to be smaller than a few x 10(-2), improving the CMB-only constraint by at least 2 orders of magnitude. We also show that coupled cosmologies can substantially alter the constraints on cosmological parameters obtained from CMB experiments under the assumption of noninteracting cosmologies unless weak lensing data is considered.
Address [De Bernardis, F; Cooray, A] Univ Calif Irvine, Dept Phys & Astron, Irvine, CA 92697 USA
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000292515000001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 681
Permanent link to this record