Search Publications
Clouds, Streams and Bridges. Redrawing the blueprint of the Magellanic System with Gaia DR1
Erkal, Denis; Belokurov, Vasily; Mackey, Dougal +5 more
We present the discovery of stellar tidal tails around the Large and the Small Magellanic Clouds (LMC and SMC, respectively) in the Gaia DR1 data. In between the Clouds, their tidal arms are stretched towards each other to form an almost continuous stellar bridge. Our analysis relies on the exquisite quality of the Gaia's photometric catalogue to …
The dust mass in Cassiopeia A from a spatially resolved Herschel analysis
De Looze, I.; Rho, J.; Gomez, H. L. +4 more
Theoretical models predict that core-collapse supernovae (CCSNe) can be efficient dust producers (0.1-1.0 M⊙), potentially accounting for most of the dust production in the early Universe. Observational evidence for this dust production efficiency is however currently limited to only a few CCSN remnants (e.g. SN 1987A, Crab nebula). In …
A radiation transfer model for the Milky Way: I. Radiation fields and application to high-energy astrophysics★
Aharonian, F.; Yang, R.; Tuffs, R. J. +3 more
We present a solution for the ultraviolet - submillimetre (submm) interstellar radiation fields (ISRFs) of the Milky Way (MW), derived from modelling COBE, IRAS and Planck maps of the all-sky emission in the near-, mid-, far-infrared and submm. The analysis uses the axisymmetric radiative transfer model that we have previously implemented to model…
The Herschel-ATLAS: a sample of 500 µm-selected lensed galaxies over 600 deg2
Ivison, R. J.; Omont, A.; Danese, L. +43 more
We present a sample of 80 candidate strongly lensed galaxies with flux density above 100 mJy at 500 µm extracted from the Herschel Astrophysical Terahertz Large Area Survey, over an area of 600 deg2. Available imaging and spectroscopic data allow us to confirm the strong lensing in 20 cases and to reject it in one case. For other …
Stellar inventory of the solar neighbourhood using Gaia DR1
Bovy, Jo
The absolute number and the density profiles of different types of stars in the solar neighbourhood are a fundamental anchor for studies of the initial mass function, stellar evolution, and Galactic structure. Using data from Gaia DR1, we reconstruct Gaia's selection function and determine Gaia's volume completeness, the local number density, and …
Galactic rotation in Gaia DR1
Bovy, Jo
The spatial variations of the velocity field of local stars provide direct evidence of Galactic differential rotation. The local divergence, shear and vorticity of the velocity field - the traditional Oort constants - can be measured based purely on astrometric measurements and in particular depend linearly on proper motion and parallax. I use dat…
Seasonal mass transfer on the nucleus of comet 67P/Chuyumov-Gerasimenko
Jorda, L.; Bertaux, J. -L.; Lamy, P. +47 more
We collect observational evidence that supports the scheme of mass transfer on the nucleus of comet 67P/Churyumov-Gerasimenko. The obliquity of the rotation axis of 67P causes strong seasonal variations. During perihelion the southern hemisphere is four times more active than the north. Northern territories are widely covered by granular material …
The production and escape of Lyman-Continuum radiation from star-forming galaxies at z ∼ 2 and their redshift evolution
Sobral, David; Khostovan, Ali Ahmad; Bouwens, Rychard +4 more
We study the production rate of ionizing photons of a sample of 588 Hα emitters (HAEs) and 160 Lyman-α emitters (LAEs) at z = 2.2 in the COSMOS field in order to assess the implied emissivity from galaxies, based on their ultraviolet (UV) luminosity. By exploring the rest-frame Lyman Continuum (LyC) with GALEX/NUV data, we find fesc <…
Multitemperature mapping of dust structures throughout the Galactic Plane using the PPMAP tool with Herschel Hi-GAL data
Palmeirim, P.; Schneider, N.; Becciani, U. +13 more
We describe new Hi-GAL based maps of the entire Galactic Plane, obtained using continuum data in the wavelength range 70-500 µm. These maps are derived with the PPMAP procedure, and therefore represent a significant improvement over those obtained with standard analysis techniques. Specifically they have greatly improved resolution (12 arcse…
HELP: XID+, the probabilistic de-blender for Herschel SPIRE maps
Le Floc'h, E.; Valtchanov, I.; Wang, L. +13 more
We have developed a new prior-based source extraction tool, XID+, to carry out photometry in the Herschel SPIRE (Spectral and Photometric Imaging Receiver) maps at the positions of known sources. XID+ is developed using a probabilistic Bayesian framework that provides a natural framework in which to include prior information, and uses the Bayesian…