Search Publications
Bayesian evidences for dark energy models in light of current observational data
Lonappan, Anto. I.; Kumar, Sumit; Ruchika +2 more
We do a comprehensive study of the Bayesian evidences for a large number of dark energy models using a combination of latest cosmological data from SNIa, CMB, BAO, strong lensing time delay, growth measurements, measurements of Hubble parameter at different redshifts and measurements of angular diameter distance by Megamaser Cosmology Project. We …
Updated observational constraints on quintessence dark energy models
Ichiki, Kiyotomo; Sugiyama, Naoshi; Ooba, Junpei +1 more
The recent GW170817 measurement favors the simplest dark energy models, such as a single scalar field. Quintessence models can be classified in two classes, freezing and thawing, depending on whether the equation of state decreases towards -1 or departs from it. In this paper, we put observational constraints on the parameters governing the equati…
Astrometric effects of gravitational wave backgrounds with non-Einsteinian polarizations
Gilmore, Gerard; Mihaylov, Deyan P.; Moore, Christopher J. +2 more
The Gaia mission offers a new opportunity to search for the low-frequency gravitational wave background using astrometric measurements. In this paper, the astrometric effect of gravitational waves is reviewed, with a particular focus on the effect of non-Einsteinian gravitational wave polarizations. A stochastic gravitational wave background gener…
Precision charge control for isolated free-falling test masses: LISA pathfinder results
Mendes, L.; Russano, G.; Lloro, I. +83 more
The LISA Pathfinder charge management device was responsible for neutralizing the cosmic-ray-induced electric charge that inevitably accumulated on the free-falling test masses at the heart of the experiment. We present measurements made on ground and in flight that quantify the performance of this contactless discharge system which was based on p…
Cornering the P l a n c k Alens tension with future CMB data
Di Valentino, Eleonora; Melchiorri, Alessandro; Renzi, Fabrizio
The precise measurements of cosmic microwave background (CMB) anisotropy angular power spectra made by the Planck satellite show an anomalous value for the lensing amplitude, defined by the parameter Alens, at about 2 standard deviations (2.6 standard deviations when cosmic shear data are included). Moreover, considering Alens
Measurement of the thermal Sunyaev-Zel'dovich effect around cosmic voids
Spergel, David N.; Alonso, David; Hill, J. Colin +1 more
We stack maps of the thermal Sunyaev-Zel'dovich effect produced by the Planck Collaboration around the centers of cosmic voids defined by the distribution of galaxies in the CMASS sample of the Baryon Oscillation Spectroscopic Survey, scaled by the void effective radii. We report a first detection of the associated cross-correlation at the 3.4 σ l…
Measurement of the pairwise kinematic Sunyaev-Zeldovich effect with Planck and BOSS data
Moodley, Kavilan; Ma, Yin-Zhe; Remazeilles, Mathieu +1 more
We present a new measurement of the kinetic Sunyaev-Zeldovich effect (kSZ) using Planck cosmic microwave background (CMB) and Baryon Oscillation Spectroscopic Survey (BOSS) data. Using the "LowZ North/South" galaxy catalogue from BOSS DR12, and the group catalogue from BOSS DR13, we evaluate the mean pairwise kSZ temperature associated with BOSS g…
Calibrating the system dynamics of LISA Pathfinder
Mendes, L.; Russano, G.; Lloro, I. +75 more
LISA Pathfinder (LPF) was a European Space Agency mission with the aim to test key technologies for future space-borne gravitational-wave observatories like LISA. The main scientific goal of LPF was to demonstrate measurements of differential acceleration between free-falling test masses at the sub-femto-g level, and to understand the residual acc…
First cosmological constraints combining Planck with the recent gravitational-wave standard siren measurement of the Hubble constant
Di Valentino, Eleonora; Melchiorri, Alessandro
The recent observations of gravitational-wave and electromagnetic emission produced by the merger of the binary neutron-star system GW170817 have opened the possibility of using standard sirens to constrain the value of the Hubble constant. While the reported bound of H0=7 0-8+12 at 68% C.L. is significantly weaker…
Probability of warm inflation in loop quantum cosmology
Ramos, Rudnei O.; Graef, L. L.
Warm inflation is analyzed in the context of loop quantum cosmology (LQC). The bounce in LQC provides a mean through which a Liouville measure can be defined, which has been used previously to characterize the a priori probability for inflation in LQC. Here we take advantage of the tools provided by LQC to study instead the a priori probability fo…