Search Publications
Strong lensing signatures of luminous structure and substructure in early-type galaxies
Treu, Tommaso; Keeton, Charles R.; Nierenberg, Anna M. +2 more
The arrival times, positions and fluxes of multiple images in strong lens systems can be used to infer the presence of dark subhaloes in the deflector, and thus test predictions of cold dark matter models. However, gravitational lensing does not distinguish between perturbations to a smooth gravitational potential arising from baryonic and non-bar…
A Survey For Planetary-mass Brown Dwarfs in the Taurus and Perseus Star-forming Regions
Luhman, K. L.; Esplin, T. L.
We present the initial results from a survey for planetary-mass brown dwarfs in the Taurus star-forming region. We have identified brown dwarf candidates in Taurus using proper motions and photometry from several ground- and space-based facilities. Through spectroscopy of some of the more promising candidates, we have found 18 new members of Tauru…
Detection of methyl isocyanate (CH3NCO) in a solar-type protostar
Testi, L.; Martín-Pintado, J.; Jiménez-Serra, I. +3 more
We report the detection of the pre-biotic molecule CH3NCO in a solar-type protostar, IRAS16293-2422 B. A significant abundance of this species on the surface of the comet 67P/Churyumov-Gerasimenko has been proposed, and it has recently been detected in hot cores around high-mass protostars. We observed IRAS16293-2422 B with the Atacama …
The faint radio sky: VLBA observations of the COSMOS field
Smolčić, V.; Momjian, E.; Schinnerer, E. +10 more
Context. Quantifying the fraction of active galactic nuclei (AGN) in the faint radio population and understanding their relation with star-forming activity are fundamental to studies of galaxy evolution. Very long baseline interferometry (VLBI) observations are able to identify AGN above relatively low redshifts (z> 0.1) since they provide mill…
The VLT-FLAMES Tarantula Survey. XXVI. Properties of the O-dwarf population in 30 Doradus
Crowther, P. A.; Lennon, D. J.; Herrero, A. +21 more
Context. The VLT-FLAMES Tarantula Survey has observed hundreds of O-type stars in the 30 Doradus region of the Large Magellanic Cloud (LMC).
Aims: We study the properties of a statistically significant sample of O-type dwarfs in the same star-forming region and test the latest atmospheric and evolutionary models of the early main-sequence pha…
Illuminating gas inflows/outflows in the MUSE deepest fields: Lyα nebulae around forming galaxies at z ≃ 3.3
Gilli, R.; Grillo, C.; Tozzi, P. +11 more
We report the identification of extended Lyα nebulae at z ≃ 3.3 in the Hubble Ultra Deep Field (HUDF, ≃40 kpc × 80 kpc) and behind the Hubble Frontier Field galaxy cluster MACSJ0416 (≃40 kpc), spatially associated with groups of star-forming galaxies. VLT/MUSE integral field spectroscopy reveals a complex structure with a spatially varying double-…
How primordial is the structure of comet 67P?. Combined collisional and dynamical models suggest a late formation
Benz, W.; Morbidelli, A.; Jutzi, M. +2 more
Context. There is an active debate about whether the properties of comets as observed today are primordial or, alternatively, if they are a result of collisional evolution or other processes.
Aims: We investigate the effects of collisions on a comet with a structure like 67P/Churyumov-Gerasimenko (67P). We develop scaling laws for the critica…
The scattering phase function of comet 67P/Churyumov-Gerasimenko coma as seen from the Rosetta/OSIRIS instrument
Jorda, L.; Lara, L. M.; Bertaux, J. -L. +52 more
The study of dust, the most abundant material in cometary nuclei, is pivotal in understanding the original materials forming the Solar system. Measuring the coma phase function provides a tool to investigate the nature of cometary dust. Rosetta/OSIRIS sampled the coma phase function of comet 67P/Churyumov-Gerasimenko, covering a large phase angle …
High energy polarimetry of prompt GRB emission
McConnell, Mark L.
[Evidence] of polarized γ-ray emission (> 50 keV) from Gamma-Ray Bursts (GRBs) has been accumulated in recent years. Measurements have been reported with levels in the range of 30-80%, typically with limited statistical significance. No clear picture has yet emerged with regards to the polarization properties of GRBs. Taken at face value, the d…
A Gaia-PS1-SDSS (GPS1) Proper Motion Catalog Covering 3/4 of the Sky
Goldman, Bertrand; Tian, Hai-Jun; Rix, Hans-Walter +7 more
We combine Gaia DR1, PS1, Sloan Digital Sky Survey (SDSS), and 2MASS astrometry to measure proper motions for 350 million sources across three-fourths of the sky down to a magnitude of {m}r∼ 20. Using positions of galaxies from PS1, we build a common reference frame for the multi-epoch PS1, single-epoch SDSS and 2MASS data, and calibrat…