Search Publications
Revisiting CMB constraints on warm inflation
Arya, Richa; Dasgupta, Arnab; Goswami, Gaurav +2 more
We revisit the constraints that Planck 2015 temperature, polarization and lensing data impose on the parameters of warm inflation. To this end, we study warm inflation driven by a single scalar field with a quartic self interaction potential in the weak dissipative regime. We analyse the effect of the parameters of warm inflation, namely, the infl…
The metal-poor stellar halo in RAVE-TGAS and its implications for the velocity distribution of dark matter
Lisanti, Mariangela; Herzog-Arbeitman, Jonah; Necib, Lina
The local velocity distribution of dark matter plays an integral role in interpreting the results from direct detection experiments. We previously showed that metal-poor halo stars serve as excellent tracers of the virialized dark matter velocity distribution using a high-resolution hydrodynamic simulation of a Milky Way-like halo. In this paper, …
Fast point spread function modeling with deep learning
Herbel, Jörg; Amara, Adam; Refregier, Alexandre +2 more
Modeling the Point Spread Function (PSF) of wide-field surveys is vital for many astrophysical applications and cosmological probes including weak gravitational lensing. The PSF smears the image of any recorded object and therefore needs to be taken into account when inferring properties of galaxies from astronomical images. In the case of cosmic …
Probing features in inflaton potential and reionization history with future CMB space observations
Ballardini, Mario; Finelli, Fabio; Paoletti, Daniela +4 more
We consider the prospects of probing features in the primordial power spectrum with future Cosmic Microwave Background (CMB) polarization measurements. In the scope of the inflationary scenario, such features in the spectrum can be produced by local non-smooth pieces in an inflaton potential (smooth and quasi-flat in general) which in turn may ori…
Exploring cosmic origins with CORE: Extragalactic sources in cosmic microwave background maps
Boulanger, F.; Ashdown, M.; Banday, A. J. +124 more
We discuss the potential of a next generation space-borne Cosmic Microwave Background (CMB) experiment for studies of extragalactic sources. Our analysis has particular bearing on the definition of the future space project, CORE, that has been submitted in response to ESA's call for a Medium-size mission opportunity as the successor of the Planck …
Exploring cosmic origins with CORE: Effects of observer peculiar motion
Boulanger, F.; Ashdown, M.; Banday, A. J. +117 more
We discuss the effects on the cosmic microwave background (CMB), cosmic infrared background (CIB), and thermal Sunyaev-Zeldovich effect due to the peculiar motion of an observer with respect to the CMB rest frame, which induces boosting effects. After a brief review of the current observational and theoretical status, we investigate the scientific…
Exploring cosmic origins with CORE: Cluster science
Boulanger, F.; Ashdown, M.; Banday, A. J. +118 more
We examine the cosmological constraints that can be achieved with a galaxy cluster survey with the future CORE space mission. Using realistic simulations of the millimeter sky, produced with the latest version of the Planck Sky Model, we characterize the CORE cluster catalogues as a function of the main mission performance parameters. We pay parti…
CMB constraints on β-exponential inflationary models
Alcaniz, J. S.; Silva, R.; Benetti, M. +2 more
We analyze a class of generalized inflationary models proposed in ref. [1], known as β-exponential inflation. We show that this kind of potential can arise in the context of brane cosmology, where the field describing the size of the extra-dimension is interpreted as the inflaton. We discuss the observational viability of this class of model in li…
A Bayesian analysis of inflationary primordial spectrum models using Planck data
Benetti, Micol; Alcaniz, Jailson; Santos da Costa, Simony
The current available Cosmic Microwave Background (CMB) data show an anomalously low value of the CMB temperature fluctuations at large angular scales (l < 40). This lack of power is not explained by the minimal ΛCDM model, and one of the possible mechanisms explored in the literature to address this problem is the presence of features in the p…
CMB constraints on running non-Gaussianity
Bartolo, N.; Liguori, M.; Renzi, A. +2 more
We develop a complete set of tools for CMB forecasting, simulation and estimation of primordial running bispectra, arising from a variety of curvaton and single-field (DBI) models of Inflation. We validate our pipeline using mock CMB running non-Gaussianity realizations and test it on real data by obtaining experimental constraints on the fNL…