Search Publications
The Canadian Cluster Comparison Project: detailed study of systematics and updated weak lensing masses
Muzzin, Adam; Hoekstra, Henk; Babul, Arif +4 more
Masses of clusters of galaxies from weak gravitational lensing analyses of ever larger samples are increasingly used as the reference to which baryonic scaling relations are compared. In this paper we revisit the analysis of a sample of 50 clusters studied as part of the Canadian Cluster Comparison Project. We examine the key sources of systematic…
Ongoing hydrothermal activities within Enceladus
Postberg, Frank; Altobelli, Nicolas; Sekine, Yasuhito +12 more
Detection of sodium-salt-rich ice grains emitted from the plume of the Saturnian moon Enceladus suggests that the grains formed as frozen droplets from a liquid water reservoir that is, or has been, in contact with rock. Gravitational field measurements suggest a regional south polar subsurface ocean of about 10 kilometres thickness located beneat…
Wind from the black-hole accretion disk driving a molecular outflow in an active galaxy
Veilleux, S.; Reynolds, C. S.; Tombesi, F. +3 more
Powerful winds driven by active galactic nuclei are often thought to affect the evolution of both supermassive black holes and their host galaxies, quenching star formation and explaining the close relationship between black holes and galaxies. Recent observations of large-scale molecular outflows in ultraluminous infrared galaxies support this qu…
The evolution of the X-ray luminosity functions of unabsorbed and absorbed AGNs out to z∼ 5
Georgakakis, A.; Nandra, K.; Aird, J. +3 more
We present new measurements of the evolution of the X-ray luminosity functions (XLFs) of unabsorbed and absorbed active galactic nuclei (AGNs) out to z ∼ 5. We construct samples containing 2957 sources detected at hard (2-7 keV) X-ray energies and 4351 sources detected at soft (0.5-2 keV) energies from a compilation of Chandra surveys supplemented…
The VIMOS Ultra-Deep Survey: ~10 000 galaxies with spectroscopic redshifts to study galaxy assembly at early epochs 2 < z ≃ 6
Maccagni, D.; Cimatti, A.; Ilbert, O. +42 more
We present the VIMOS Ultra Deep Survey (VUDS), a spectroscopic redshift survey of ~10 000 very faint galaxies to study the main phase of galaxy assembly in 2 < z ≃ 6. The survey covers 1 deg2 in three separate fields: COSMOS, ECDFS, and VVDS-02h, with the selection of targets based on an inclusive combination of photometric redshifts…
A dusty, normal galaxy in the epoch of reionization
Richard, Johan; Gallazzi, Anna; Christensen, Lise +3 more
Candidates for the modest galaxies that formed most of the stars in the early Universe, at redshifts z > 7, have been found in large numbers with extremely deep restframe-ultraviolet imaging. But it has proved difficult for existing spectrographs to characterize them using their ultraviolet light. The detailed properties of these galaxies could…
On the nucleus structure and activity of comet 67P/Churyumov-Gerasimenko
Bertaux, Jean-Loup; Da Deppo, Vania; Naletto, Giampiero +63 more
Images from the OSIRIS scientific imaging system onboard Rosetta show that the nucleus of 67P/Churyumov-Gerasimenko consists of two lobes connected by a short neck. The nucleus has a bulk density less than half that of water. Activity at a distance from the Sun of >3 astronomical units is predominantly from the neck, where jets have been seen c…
Fundamental Parameters and Spectral Energy Distributions of Young and Field Age Objects with Masses Spanning the Stellar to Planetary Regime
Faherty, Jacqueline; Cruz, Kelle L.; Rice, Emily L. +3 more
We combine optical, near-infrared, and mid-infrared spectra and photometry to construct expanded spectral energy distributions for 145 field age (>500 Myr) and 53 young (lower age estimate <500 Myr) ultracool dwarfs (M6-T9). This range of spectral types includes very low mass stars, brown dwarfs, and planetary mass objects, providing fundame…
Faint AGNs at z > 4 in the CANDELS GOODS-S field: looking for contributors to the reionization of the Universe
Dickinson, M.; Salvato, M.; Fiore, F. +14 more
Context. Establishing the number of faint active galactic nuclei (AGNs) at z = 4-6 is crucial to understanding their cosmological importance as main contributors to the reionization of the Universe.
Aims: In order to derive the AGN contribution to the cosmological ionizing emissivity we have selected faint AGN candidates at z> 4 in the CAN…
Neutrino physics from the cosmic microwave background and large scale structure
Hu, W.; Bond, J. R.; Borrill, J. +74 more
This is a report on the status and prospects of the quantification of neutrino properties through the cosmological neutrino background for the Cosmic Frontier of the Division of Particles and Fields Community Summer Study long-term planning exercise. Experiments planned and underway are prepared to study the cosmological neutrino background in det…