Search Publications
Hubble Space Telescope transmission spectroscopy of the exoplanet HD 189733b: high-altitude atmospheric haze in the optical and near-ultraviolet with STIS
Mazeh, T.; Aigrain, S.; Pont, F. +10 more
We present Hubble Space Telescope (HST) optical and near-ultraviolet transmission spectra of the transiting hot Jupiter HD 189733b, taken with the repaired Space Telescope Imaging Spectrograph (STIS) instrument. The resulting spectra cover the range 2900-5700 Å and reach per exposure signal-to-noise ratio levels greater than 11 000 within a 500-Å …
Luminous blue variable eruptions and related transients: diversity of progenitors and outburst properties
Filippenko, Alexei V.; Smith, Nathan; Li, Weidong +2 more
We present new light curves and optical spectra for a number of extragalactic optical transients or 'supernova impostors' related to giant eruptions of luminous blue variables (LBVs), and we provide a comparative discussion of LBV-like giant eruptions known thus far. New data include photometry and spectroscopy of supernovae (SNe) 1999bw, 2000ch, …
Creation of cosmic structure in the complex galaxy cluster merger Abell 2744
Okabe, N.; Zitrin, A.; Meneghetti, M. +15 more
We present a detailed strong-lensing, weak-lensing and X-ray analysis of Abell 2744 (z= 0.308), one of the most actively merging galaxy clusters known. It appears to have unleashed 'dark', 'ghost', 'bullet' and 'stripped' substructures, each ∼1014 M⊙. The phenomenology is complex and will present a challenge for numerical sim…
Two-dimensional kinematics of SLACS lenses - III. Mass structure and dynamics of early-type lens galaxies beyond z ≃ 0.1
Treu, Tommaso; Czoske, Oliver; Koopmans, Léon V. E. +2 more
We combine in a self-consistent way the constraints from both gravitational lensing and stellar kinematics to perform a detailed investigation of the internal mass distribution, amount of dark matter, and dynamical structure of the 16 early-type lens galaxies from the SLACS Survey, at z = 0.08 - 0.33, for which both HST/ACS and NICMOS high-resolut…
Discovery of the nearby long, soft GRB 100316D with an associated supernova
Sakamoto, T.; Covino, S.; D'Avanzo, P. +43 more
We report the Swift discovery of the nearby long, soft gamma-ray burst GRB 100316D, and the subsequent unveiling of its low-redshift host galaxy and associated supernova. We derive the redshift of the event to be z= 0.0591 ± 0.0001 and provide accurate astrometry for the gamma-ray burst (GRB) supernova (SN). We study the extremely unusual prompt e…
A robust sample of galaxies at redshifts 6.0<z<8.7: stellar populations, star formation rates and stellar masses
Bowler, R. A. A.; McLure, R. J.; Dunlop, J. S. +7 more
We present the results of a photometric redshift analysis designed to identify z≥ 6 galaxies from the near-infrared Hubble Space Telescope imaging in three deep fields [Hubble Ultra Deep Field (HUDF), HUDF09-2 and Early Release Science] covering a total area of 45 square arcmin. By adopting a rigorous set of criteria for rejecting low-redshift int…
Dynamical masses of early-type galaxies: a comparison to lensing results and implications for the stellar initial mass function and the distribution of dark matter
Saglia, R. P.; Thomas, D.; Thomas, J. +6 more
This work aims to study the distribution of the luminous and dark matter in Coma early-type galaxies. Dynamical masses obtained under the assumption that mass follows light do not match with the masses of strong gravitational lens systems of similar velocity dispersions. Instead, dynamical fits with dark matter haloes are in good agreement with le…
Families of dynamically hot stellar systems over 10 orders of magnitude in mass
Hilker, M.; Misgeld, I.
Dynamically hot stellar systems, whether star clusters or early-type galaxies, follow well-defined scaling relations over many orders of magnitudes in mass. These Fundamental Plane relations have been subject of several studies, which have been mostly confined to certain types of galaxies and/or star clusters so far. Here, we present a complete pi…
The dependence of star formation activity on environment and stellar mass at z∼ 1 from the HiZELS-Hα survey
Smail, Ian; Sobral, David; Geach, James E. +4 more
This paper presents an environment and stellar mass study of a large sample of star-forming Hα emitters at z= 0.84 from the High-z Emission Line Survey (HiZELS), over 1.3 deg2 split over two fields (COSMOS and UKIDSS UDS). By taking advantage of a truly panoramic coverage of a wide range of environments, from the field to a rich cluster…
Dissecting the size evolution of elliptical galaxies since z∼ 1: puffing-up versus minor-merging scenarios
Trujillo, Ignacio; Ferreras, Ignacio; de La Rosa, Ignacio G.
At a fixed stellar mass, the size of low-redshift early-type galaxies is found to be a factor of 2 larger than that of their counterparts at z∼ 1, a result with important implications for galaxy formation models. In this paper, we have explored the buildup of the local mass-size relation of elliptical galaxies using two visually classified samples…