|   | 
Details
   web
Records
Author Semikoz, V.B.; Valle, J.W.F.
Title Chern-Simons anomaly as polarization effect Type Journal Article
Year (down) 2011 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 11 Issue 11 Pages 048
Keywords
Abstract The parity violating, Chern-Simons term in the epoch before the electroweak phase transition can be interpreted as a polarization effect associated to massless right-handed electrons (positrons) in the presence of a large-scale seed hypermagnetic field. We reconfirm the viability of a unified seed field scenario relating the cosmological baryon asymmetry and the origin of the protogalactic large-scale magnetic fields observed in astronomy.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:000298141300048 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 866
Permanent link to this record
 

 
Author Cervantes-Cota, J.L.; de Putter, R.; Linder, E.V.
Title Induced gravity and the attractor dynamics of dark energy/dark matter Type Journal Article
Year (down) 2010 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 12 Issue 12 Pages 019 - 20pp
Keywords modified gravity; dark energy theory
Abstract Attractor solutions that give dynamical reasons for dark energy to act like the cosmological constant, or behavior close to it, are interesting possibilities to explain cosmic acceleration. Coupling the scalar field to matter or to gravity enlarges the dynamical behavior; we consider both couplings together, which can ameliorate some problems for each individually. Such theories have also been proposed in a Higgs-like fashion to induce gravity and unify dark energy and dark matter origins. We explore restrictions on such theories due to their dynamical behavior compared to observations of the cosmic expansion. Quartic potentials in particular have viable stability properties and asymptotically approach general relativity.
Address [Cervantes-Cota, Jorge L.] Inst Nacl Invest Nucl, Dept Fis, Mexico City 11801, DF, Mexico, Email: jorge.cervantes@inin.gob.mx
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes ISI:000286930700019 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 533
Permanent link to this record
 

 
Author Pierre Auger Collaboration (Abreu, P. et al); Pastor, S.
Title Update on the correlation of the highest energy cosmic rays with nearby extragalactic matter Type Journal Article
Year (down) 2010 Publication Astroparticle Physics Abbreviated Journal Astropart Phys.
Volume 34 Issue 5 Pages 314-326
Keywords Cosmic rays; UHECR; Anisotropy; Pierre Auger Observatory; Extra-galactic; GZK
Abstract Data collected by the Pierre Auger Observatory through 31 August 2007 showed evidence for anisotropy in the arrival directions of cosmic rays above the Greisen-Zatsepin-Kuz'min energy threshold, 6 x 10(19) eV. The anisotropy was measured by the fraction of arrival directions that are less than 3.1 degrees from the position of an active galactic nucleus within 75 Mpc (using the Veron-Cetty and Veron 12th catalog). An updated measurement of this fraction is reported here using the arrival directions of cosmic rays recorded above the same energy threshold through 31 December 2009. The number of arrival directions has increased from 27 to 69, allowing a more precise measurement. The correlating fraction is (38(-6)(+7))%, compared with 21% expected for isotropic cosmic rays. This is down from the early estimate of (69-(+11)(13))%. The enlarged set of arrival directions is examined also in relation to other populations of nearby extragalactic objects: galaxies in the 2 Microns All Sky Survey and active galactic nuclei detected in hard X-rays by the Swift Burst Alert Telescope. A celestial region around the position of the radiogalaxy Cen A has the largest excess of arrival directions relative to isotropic expectations. The 2-point autocorrelation function is shown for the enlarged set of arrival directions and compared to the isotropic expectation.
Address [Allekotte, I.; Asorey, H.; Bertou, X.; Golup, G.; Gomez Berisso, M.; Harari, D.; Mollerach, S.; Ponce, V. H.; Roulet, E.] Ctr Atom Bariloche, San Carlos De Bariloche, Rio Negro, Argentina
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0927-6505 ISBN Medium
Area Expedition Conference
Notes ISI:000284669100007 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 320
Permanent link to this record
 

 
Author Gavela, M.B.; Lopez Honorez, L.; Mena, O.; Rigolin, S.
Title Dark coupling and gauge invariance Type Journal Article
Year (down) 2010 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 11 Issue 11 Pages 044 - 15pp
Keywords cosmological perturbation theory; dark energy theory; dark energy experiments
Abstract
Address [Gavela, M. B.; Lopez Honorez, L.] Univ Autonoma Madrid IFT UAM CSIC, Dept Fis Teor, Madrid 28049, Spain, Email: belen.gavela@uam.es
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes ISI:000284825100044 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 316
Permanent link to this record
 

 
Author Carbone, C.; Mena, O.; Verde, L.
Title Cosmological parameters degeneracies and non-Gaussian halo bias Type Journal Article
Year (down) 2010 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 07 Issue 7 Pages 020 - 17pp
Keywords power spectrum; redshift surveys; galaxy clusters; cosmological parameters from LSS
Abstract We study the impact of the cosmological parameters uncertainties on the measurements of primordial non-Gaussianity through the large-scale non-Gaussian halo bias effect. While this is not expected to be an issue for the standard Lambda CDM model, it may not be the case for more general models that modify the large-scale shape of the power spectrum. We consider the so-called local non-Gaussianity model, parametrized by the f(NL) non-Gaussianity parameter which is zero for a Gaussian case, and make forecasts on f(NL) from planned surveys, alone and combined with a Planck CMB prior. In particular, we consider EUCLID- and LSST-like surveys and forecast the correlations among f(NL) and the running of the spectral index alpha(s), the dark energy equation of state w, the effective sound speed of dark energy perturbations c(s)(2), the total mass of massive neutrinos M-nu = Sigma m(nu), and the number of extra relativistic degrees of freedom N-nu(rel). Neglecting CMB information on f(NL) and scales k > 0.03h/Mpc, we find that, if N-nu(rel) is assumed to be known, the uncertainty on cosmological parameters increases the error on f(NL) by 10 to 30% depending on the survey. Thus the f(NL) constraint is remarkable robust to cosmological model uncertainties. On the other hand, if N-nu(rel) is simultaneously constrained from the data, the f(NL) error increases by similar to 80%. Finally, future surveys which provide a large sample of galaxies or galaxy clusters over a volume comparable to the Hubble volume can measure primordial non-Gaussianity of the local form with a marginalized 1-sigma error of the order Delta f(NL) similar to 2 – 5, after combination with CMB priors for the remaining cosmological parameters. These results are competitive with CMB bispectrum constraints achievable with an ideal CMB experiment.
Address [Carbone, Carmelita] Univ Bologna, Dipartimento Astron, I-40127 Bologna, Italy, Email: carmelita.carbone@unibo.it
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes ISI:000283573200010 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 347
Permanent link to this record