Search Publications
Sub-Femto-g Free Fall for Space-Based Gravitational Wave Observatories: LISA Pathfinder Results
Mendes, L.; Madden, S.; Russano, G. +116 more
We report the first results of the LISA Pathfinder in-flight experiment. The results demonstrate that two free-falling reference test masses, such as those needed for a space-based gravitational wave observatory like LISA, can be put in free fall with a relative acceleration noise with a square root of the power spectral density of 5.2 ±0.1 fm s
Kinematic Sunyaev-Zel'dovich Effect with Projected Fields: A Novel Probe of the Baryon Distribution with Planck, WMAP, and WISE Data
Spergel, David N.; Ferraro, Simone; Hill, J. Colin +2 more
The kinematic Sunyaev-Zel'dovich (KSZ) effect—the Doppler boosting of cosmic microwave background (CMB) photons due to Compton scattering off free electrons with nonzero bulk velocity—probes the abundance and the distribution of baryons in the Universe. All KSZ measurements to date have explicitly required spectroscopic redshifts. Here, we impleme…
How Isotropic is the Universe?
Peiris, Hiranya V.; Feeney, Stephen M.; Pontzen, Andrew +2 more
A fundamental assumption in the standard model of cosmology is that the Universe is isotropic on large scales. Breaking this assumption leads to a set of solutions to Einstein's field equations, known as Bianchi cosmologies, only a subset of which have ever been tested against data. For the first time, we consider all degrees of freedom in these s…
Demonstration of Cosmic Microwave Background Delensing Using the Cosmic Infrared Background
Sherwin, Blake D.; Challinor, Anthony; Larsen, Patricia +1 more
Delensing is an increasingly important technique to reverse the gravitational lensing of the cosmic microwave background (CMB) and thus reveal primordial signals the lensing may obscure. We present a first demonstration of delensing on Planck temperature maps using the cosmic infrared background (CIB). Reversing the lensing deflections in Planck C…
Observational Test for a Random Sweeping Model in Solar Wind Turbulence
Glassmeier, K. H.; Narita, Y.; Perschke, C. +1 more
Evidence of frequency broadening at ion kinetic scales due to large-scale eddies and waves is found in solar wind turbulence by a test for a random sweeping model using the magnetic energy spectrum in the frequency vs wave number domain in the comoving frame of the flow obtained from multispacecraft observations. The statistical analysis of the fr…
Nonlinear Waves in the Terrestrial Quasiparallel Foreshock
Nakariakov, V. M.; Hnat, B.; Kolotkov, D. Y. +2 more
We provide strongly conclusive evidence that the cubic nonlinearity plays an important part in the evolution of the large amplitude magnetic structures in the terrestrial foreshock. Large amplitude nonlinear wave trains at frequencies above the proton cyclotron frequency are identified after nonharmonic slow variations are filtered out by applying…
Joint Analysis of BICEP2/Keck Array and Planck Data
Kneissl, R.; Miville-Deschênes, M. -A.; Boulanger, F. +277 more
We report the results of a joint analysis of data from BICEP2/Keck Array and Planck. BICEP2 and Keck Array have observed the same approximately 400 deg2 patch of sky centered on RA 0 h, Dec. -57.5 ° . The combined maps reach a depth of 57 nK deg in Stokes Q and U in a band centered at 150 GHz. Planck has observed the full sky in polariz…
Checking the Dark Matter Origin of a 3.53 keV Line with the Milky Way Center
Boyarsky, A.; Franse, J.; Iakubovskyi, D. +1 more
We detect a line at 3.539 ±0.011 keV in the deep exposure data set of the Galactic center region, observed with the x-ray multi-mirror mission Newton. The dark matter interpretation of the signal observed in the Perseus galaxy cluster, the Andromeda galaxy [A. Boyarsky et al., Phys. Rev. Lett. 113, 251301 (2014)], and in the stacked spectra of gal…
Observing Inflationary Reheating
Ringeval, Christophe; Martin, Jérôme; Vennin, Vincent
Reheating is the epoch which connects inflation to the subsequent hot big-bang phase. Conceptually very important, this era is, however, observationally poorly known. We show that the current Planck satellite measurements of the cosmic microwave background (CMB) anisotropies constrain the kinematic properties of the reheating era for most of the i…
First Detection of the Acoustic Oscillation Phase Shift Expected from the Cosmic Neutrino Background
Follin, Brent; Knox, Lloyd; Millea, Marius +1 more
The unimpeded relativistic propagation of cosmological neutrinos prior to recombination of the baryon-photon plasma alters gravitational potentials and therefore the details of the time-dependent gravitational driving of acoustic oscillations. We report here a first detection of the resulting shifts in the temporal phase of the oscillations, which…