Search Publications
Cosmological constraints on exotic injection of electromagnetic energy
Lesgourgues, Julien; Poulin, Vivian; Serpico, Pasquale D.
We compute cosmic microwave background (CMB) anisotropy constraints on exotic forms of energy injection in electromagnetic (e.m.) channels over a large range of timescales. We show that these constraints are very powerful around or just after recombination, although CMB keeps some sensitivity e.g. to decaying species with lifetimes as long as 10
The Atacama Cosmology Telescope: two-season ACTPol spectra and parameters
Hilton, Matt; Hasselfield, Matthew; Battaglia, Nicholas +80 more
We present the temperature and polarization angular power spectra measured by the Atacama Cosmology Telescope Polarimeter (ACTPol). We analyze night-time data collected during 2013-14 using two detector arrays at 149 GHz, from 548 deg2 of sky on the celestial equator. We use these spectra, and the spectra measured with the MBAC camera o…
Galileon gravity in light of ISW, CMB, BAO and H0 data
Barreira, Alexandre; Montanari, Francesco; Renk, Janina +1 more
Cosmological models with Galileon gravity are an alternative to the standard ΛCDM paradigm with testable predictions at the level of its self-accelerating solutions for the expansion history, as well as large-scale structure formation. Here, we place constraints on the full parameter space of these models using data from the cosmic microwave backg…
Constraints on neutrino masses from Lyman-alpha forest power spectrum with BOSS and XQ-100
Palanque-Delabrouille, Nathalie; Yèche, Christophe; Baur, Julien +1 more
We present constraints on masses of active and sterile neutrinos in the context of the ΛCDMν and ΛWDM models, respectively. We use the one-dimensional Lyα-forest power spectrum from the Baryon Oscillation Spectroscopic Survey (BOSS) of the Sloan Digital Sky Survey (SDSS-III) measured by Palanque-Delabrouille et al. [1], and from the VLT/XSHOOTER l…
A tale of two modes: neutrino free-streaming in the early universe
Knox, Lloyd; Pan, Zhen; Lancaster, Lachlan +1 more
We present updated constraints on the free-streaming nature of cosmological neutrinos from cosmic microwave background (CMB) temperature and polarization power spectra, baryonic acoustic oscillation data, and distance ladder measurements of the Hubble constant. Specifically, we consider a Fermi-like four-fermion interaction between massless neutri…
Interacting neutrinos in cosmology: exact description and constraints
Tram, Thomas; Wong, Yvonne Y. Y.; Oldengott, Isabel M. +1 more
We consider the impact of neutrino self-interactions described by an effective four-fermion coupling on cosmological observations. Implementing the exact Boltzmann hierarchy for interacting neutrinos first derived in [1] into the Boltzmann solver CLASS, we perform a detailed numerical analysis of the effects of the interaction on the cosmic microw…
Constraints on interacting dark energy models from Planck 2015 and redshift-space distortion data
Costa, André A.; Abdalla, E.; Wang, Bin +1 more
We investigate phenomenological interactions between dark matter and dark energy and constrain these models by employing the most recent cosmological data including the cosmic microwave background radiation anisotropies from Planck 2015, Type Ia supernovae, baryon acoustic oscillations, the Hubble constant and redshift-space distortions. We find t…
Lensing substructure quantification in RXJ1131-1231: a 2 keV lower bound on dark matter thermal relic mass
Amara, Adam; Refregier, Alexandre; Birrer, Simon
We study the substructure content of the strong gravitational lens RXJ1131-1231 through a forward modelling approach that relies on generating an extensive suite of realistic simulations. We use a semi-analytic merger tree prescription that allows us to stochastically generate substructure populations whose properties depend on the dark matter par…
Determining H0 with Bayesian hyper-parameters
Kunz, Martin; Pettorino, Valeria; Cardona, Wilmar
We re-analyse recent Cepheid data to estimate the Hubble parameter H0 by using Bayesian hyper-parameters (HPs). We consider the two data sets from Riess et al. 2011 and 2016 (labelled R11 and R16, with R11 containing less than half the data of R16) and include the available anchor distances (megamaser system NGC4258, detached eclipsing …
Observational constraints on successful model of quintessential Inflation
Starobinsky, Alexei A.; Geng, Chao-Qiang; Lee, Chung-Chi +2 more
We study quintessential inflation using a generalized exponential potential V(phi)propto \exp(-λ phin/MPln), n>1, the model admits slow-roll inflation at early times and leads to close-to-scaling behaviour in the post inflationary era with an exit to dark energy at late times. We present detailed investigations …