Search Publications
Detection of atmospheric haze on an extrasolar planet: the 0.55-1.05 µm transmission spectrum of HD 189733b with the HubbleSpaceTelescope
Moutou, C.; Pont, F.; Knutson, H. +2 more
The nearby transiting planet HD 189733b was observed during three transits with the Advanced Camera for Surveys of the Hubble Space Telescope in spectroscopic mode. The resulting time-series of 675 spectra covers the 550-1050 nm range, with a resolution element of ~8 nm, at extremely high accuracy (signal-to-noise ratio up to 10000 in 50-nm interv…
Galaxy merger morphologies and time-scales from simulations of equal-mass gas-rich disc mergers
Lotz, Jennifer M.; Primack, Joel R.; Jonsson, Patrik +1 more
A key obstacle to understanding the galaxy merger rate and its role in galaxy evolution is the difficulty in constraining the merger properties and time-scales from instantaneous snapshots of the real Universe. The most common way to identify galaxy mergers is by morphology, yet current theoretical calculations of the time-scales for galaxy distur…
Homogeneous studies of transiting extrasolar planets - I. Light-curve analyses
Southworth, John
I present a homogeneous analysis of the transit light curves of 14 well-observed transiting extrasolar planets. The light curves are modelled using JKTEBOP, random errors are measured using Monte Carlo simulations and the effects of correlated noise are included using a residual-permutation algorithm. The importance of stellar limb darkening on th…
The structures of distant galaxies - I. Galaxy structures and the merger rate to z ~ 3 in the Hubble Ultra-Deep Field
Conselice, Christopher J.; Rajgor, Sheena; Myers, Robert
This paper begins a series in which we examine the structures of distant galaxies to directly determine the history of their formation modes. We start this series by examining the structures of zF850LP < 27 galaxies in the Hubble Ultra-Deep Field (UDF), the deepest high-resolution optical image taken to date. We investigate a few bas…
On the star formation rate - brightest cluster relation: estimating the peak star formation rate in post-merger galaxies
Bastian, N.
We further the recent discussion on the relation between the star formation rate (SFR) of a galaxy and the luminosity of its brightest star cluster (SFR versus MbrightestV). We first show that the observed trend of SFR versus MbrightestV is due to the brightest cluster in a galaxy being preferentially yo…
Black holes and core expansion in massive star clusters
Davies, M. B.; Mackey, A. D.; Wilkinson, M. I. +1 more
In this study we present the results from realistic N-body modelling of massive star clusters in the Magellanic Clouds. We have computed eight simulations with N ~ 105 particles; six of these were evolved for at least a Hubble time. The aim of this modelling is to examine in detail the possibility of large-scale core expansion in massiv…
Chandra unveils a binary active galactic nucleus in Mrk 463
Guainazzi, Matteo; Bianchi, Stefano; Piconcelli, Enrico +2 more
We analyse Chandra, XMM-Newton and Hubble Space Telescope (HST) data of the double-nucleus Ultraluminous Infrared Galaxy (ULIRG), Mrk 463. The Chandra detection of two luminous (L2-10keV = 1.5 × 1043 and 3.8 × 1042 erg cm-2 s-1), unresolved nuclei in Mrk 463 indicates that this galaxy hosts a …
The fraction of second generation stars in globular clusters from the analysis of the horizontal branch
D'Antona, F.; Caloi, V.
The majority of globular clusters show chemical inhomogeneities in the composition of their stars, apparently due to a second stellar generation in which the forming gas is enriched by hot-CNO cycled material processed in stars belonging to a first stellar generation. Clearly this evidence prompts questions on the modalities of formation of globul…
Mapping of molecular gas inflow towards the Seyfert nucleus of NGC4051 using Gemini NIFS
Storchi-Bergmann, Thaisa; Riffel, Rogemar A.; Winge, Cláudia +3 more
We present 2D stellar and gaseous kinematics of the inner ~130×180 pc2 of the Narrow-Line Seyfert 1 galaxy NGC4051 at a sampling of 4.5pc, from near-infrared K-band spectroscopic observations obtained with the Gemini's Near-infrared Integral Field Spectrograph (NIFS) operating with the ALTAIR adaptive optics module. We have used the CO …
Precision photometric redshift calibration for galaxy-galaxy weak lensing
Kneib, J. -P.; Cunha, C. E.; Bolzonella, M. +26 more
Accurate photometric redshifts are among the key requirements for precision weak lensing measurements. Both the large size of the Sloan Digital Sky Survey (SDSS) and the existence of large spectroscopic redshift samples that are flux-limited beyond its depth have made it the optimal data source for developing methods to properly calibrate photomet…