Search Publications
Probing the haze in the atmosphere of HD 189733b with Hubble Space Telescope/WFC3 transmission spectroscopy
Aigrain, S.; Pont, F.; Gibson, N. P. +6 more
We present Hubble Space Telescope near-infrared transmission spectroscopy of the transiting exoplanet HD 189733b, using the Wide Field Camera 3 (WFC3). This consists of time series spectra of two transits, used to measure the wavelength dependence of the planetary radius. These observations aim to test whether the Rayleigh scattering haze detected…
The Herschel Multi-tiered Extragalactic Survey: SPIRE-mm photometric redshifts
Aussel, H.; Elbaz, D.; Pérez-Fournon, I. +78 more
We investigate the potential of submm-mm and submm-mm-radio photometric redshifts using a sample of mm-selected sources as seen at 250, 350 and 500µm by the SPIRE instrument on Herschel. From a sample of 63 previously identified mm sources with reliable radio identifications in the Great Observatories Origins Deep Survey North and Lockman Ho…
Anisotropy in Space Plasma Turbulence: Solar Wind Observations
Horbury, T. S.; Chen, C. H. K.; Wicks, R. T.
The local magnetic field induces many types of anisotropy in plasma turbulence, changing the rate of energy transfer and affecting the propagation of energetic particles. It is challenging to measure this anisotropy in the solar wind due to the limited number of sampling points and measurement difficulties and many aspects remain poorly understood…
Particle Acceleration in Turbulence and Weakly Stochastic Reconnection
Lazarian, A.; Kowal, Grzegorz; de Gouveia Dal Pino, Elisabete M.
In this Letter we analyze the energy distribution evolution of test particles injected in three dimensional (3D) magnetohydrodynamic (MHD) simulations of different magnetic reconnection configurations. When considering a single Sweet-Parker topology, the particles accelerate predominantly through a first-order Fermi process, as predicted in and de…
An Integral Field Study of Abundance Gradients in nearby Luminous Infrared Galaxies
Rupke, D. S. N.; Kewley, L. J.; Dopita, M. A. +2 more
We present for the first time metallicity maps generated using data from the Wide Field Spectrograph on the ANU 2.3 m of 10 luminous infrared galaxies (LIRGs) and discuss the abundance gradients and distribution of metals in these systems. We have carried out optical integral field spectroscopy (IFS) of several LIRGs in various merger phases to in…
Ion Acceleration at the Earth's Bow Shock
Möbius, E.; Scholer, M.; Burgess, D.
The Earth's bow shock is the most studied example of a collisionless shock in the solar system. It is also widely used to model or predict the behaviour at other astrophysical shock systems. Spacecraft observations, theoretical modelling and numerical simulations have led to a detailed understanding of the bow shock structure, the spatial organiza…
Quantitative Spectroscopy of Blue Supergiant Stars in the Disk of M81: Metallicity, Metallicity Gradient, and Distance
Bresolin, Fabio; Kudritzki, Rolf-Peter; Urbaneja, Miguel A. +4 more
The quantitative spectral analysis of low-resolution (~5 Å) Keck LRIS spectra of blue supergiants in the disk of the giant spiral galaxy M81 is used to determine stellar effective temperatures, gravities, metallicities, luminosities, interstellar reddening, and a new distance using the flux-weighted gravity-luminosity relationship. Substantial red…
The Fermi GBM Gamma-Ray Burst Catalog: The First Two Years
Goldstein, Adam; Preece, Robert D.; Kouveliotou, Chryssa +26 more
The Fermi Gamma-ray Burst Monitor (GBM) is designed to enhance the scientific return from Fermi in studying gamma-ray bursts (GRBs). In its first two years of operation GBM triggered on 491 GRBs. We summarize the criteria used for triggering and quantify the general characteristics of the triggered GRBs, including their locations, durations, peak …
The heating of dust by old stellar populations in the bulge of M31
Schinnerer, Eva; Rix, Hans-Walter; Walter, Fabian +9 more
We use new Herschel multiband imaging of the Andromeda galaxy to analyse how dust heating occurs in the central regions of galaxy spheroids that are essentially devoid of young stars. We construct a dust temperature map of M31 through fitting modified blackbodies to the Herschel data, and find that the temperature within 2 kpc rises strongly from …
Herschel measurements of the D/H and 16O/18O ratios in water in the Oort-cloud comet C/2009 P1 (Garradd)
Küppers, M.; Hartogh, P.; Lellouch, E. +19 more
The D/H ratio in cometary water is believed to be an important indicator of the conditions under which icy planetesimals formed and can provide clues to the contribution of comets to the delivery of water and other volatiles to Earth. Available measurements suggest that there is isotopic diversity in the comet population. The Herschel Space Observ…