Search Publications
Inflationary features and shifts in cosmological parameters from Planck 2015 data
Dvorkin, Cora; Obied, Georges; Miranda, Vinicius +2 more
We explore the relationship between features in the Planck 2015 temperature and polarization data, shifts in the cosmological parameters, and features from inflation. Residuals in the temperature data from the best-fit power-law Λ CDM model at low multipole ℓ≲40 are mainly responsible for the high H0 and low σ8Ωm
Baryons still trace dark matter: Probing CMB lensing maps for hidden isocurvature
Muñoz, Julian B.; Grin, Daniel; Smith, Tristan L. +2 more
Compensated isocurvature perturbations (CIPs) are primordial fluctuations that balance baryon and dark-matter isocurvature to leave the total matter density unperturbed. The effects of CIPs on the cosmic microwave background (CMB) anisotropies are similar to those produced by weak lensing of the CMB: smoothing of the power spectrum and generation …
Constraining f (R ) gravity with Sunyaev-Zel'dovich clusters detected by the Planck satellite
Viel, Matteo; Peirone, Simone; Raveri, Marco +2 more
Clusters of galaxies have the potential of providing powerful constraints on possible deviations from General Relativity. We use the catalog of Sunyaev-Zel'dovich (SZ) sources detected by Planck and consider a correction to the halo mass function for a f (R ) class of modified gravity models, which has been recently found to reproduce well results…
Cosmological searches for a noncold dark matter component
Mena, Olga; Gariazzo, Stefano; Diamanti, Roberta +1 more
We explore an extended cosmological scenario where the dark matter is an admixture of cold and additional noncold species. The mass and temperature of the noncold dark matter particles are extracted from a number of cosmological measurements. Among others, we consider tomographic weak lensing data and Milky Way dwarf satellite galaxy counts. We al…
Line-of-sight extrapolation noise in dust polarization
Dodelson, Scott; Poh, Jason
The B-modes of polarization at frequencies ranging from 50-1000 GHz are produced by Galactic dust, lensing of primordial E-modes in the cosmic microwave background (CMB) by intervening large scale structure, and possibly by primordial B-modes in the CMB imprinted by gravitational waves produced during inflation. The conventional method used to sep…
Constraining holographic cosmology using Planck data
Afshordi, Niayesh; Gould, Elizabeth; Skenderis, Kostas
Holographic cosmology offers a novel framework for describing the very early Universe in which cosmological predictions are expressed in terms of the observables of a three-dimensional quantum field theory (QFT). This framework includes conventional slow-roll inflation, which is described in terms of a strongly coupled QFT, but it also allows for …
Effects of electrically charged dark matter on cosmic microwave background anisotropies
Yoshida, Naoki; Kohri, Kazunori; Kamada, Ayuki +1 more
We examine the possibility that dark matter consists of charged massive particles (CHAMPs) in view of the cosmic microwave background (CMB) anisotropies. The evolution of cosmological perturbations of CHAMPs with other components is followed in a self-consistent manner, without assuming that CHAMPs and baryons are tightly coupled. We incorporate f…
Constraining scalar-Gauss-Bonnet inflation by reheating, unitarity, and Planck data
Bhattacharjee, Srijit; Maity, Debaprasad; Mukherjee, Rupak
We revisit the inflationary dynamics in detail for theories with Gauss-Bonnet gravity coupled to scalar functions, in light of the Planck data. Considering the chaotic inflationary scenario, we constrain the parameters of two models involving inflaton-Gauss-Bonnet coupling by current Planck data. For nonzero inflaton-Gauss-Bonnet coupling β , an i…
Integrated cosmological probes: Extended analysis
Amara, Adam; Refregier, Alexandre; Nicola, Andrina
Recent progress in cosmology has relied on combining different cosmological probes. In an earlier work, we implemented an integrated approach to cosmology where the probes are combined into a common framework at the map level. This has the advantage of taking full account of the correlations between the different probes, to provide a stringent tes…
Molecular clouds as origin of the Fermi gamma-ray GeV excess
Biermann, Peter L.; de Boer, Wim; Bosse, Léo +2 more
The so-called GeV excess of the diffuse Galactic gamma-ray emission, as observed by the Fermi-LAT satellite, is studied with a spectral template fit based on energy spectra for each relevant process of gamma-ray emission. This has the advantage over "conventional" analysis because one includes the spectral knowledge of physical processes into the …