Search Publications
A study of the gas-star formation relation over cosmic time
Lutz, D.; Förster Schreiber, N. M.; Genzel, R. +19 more
We use the first systematic data sets of CO molecular line emission in z ~ 1-3 normal star-forming galaxies (SFGs) for a comparison of the dependence of galaxy-averaged star formation rates on molecular gas masses at low and high redshifts, and in different galactic environments. Although the current high-z samples are still small and biased towar…
The R136 star cluster hosts several stars whose individual masses greatly exceed the accepted 150Msolar stellar mass limit
Parker, Richard J.; Crowther, Paul A.; Goodwin, Simon P. +4 more
Spectroscopic analyses of hydrogen-rich WN5-6 stars within the young star clusters NGC3603 and R136 are presented, using archival Hubble Space Telescope and Very Large Telescope spectroscopy, and high spatial resolution near-IR photometry, including Multi-Conjugate Adaptive Optics Demonstrator (MAD) imaging of R136. We derive high stellar temperat…
The WiggleZ Dark Energy Survey: survey design and first data release
Glazebrook, Karl; Pimbblet, Kevin A.; Drinkwater, Michael J. +24 more
The WiggleZ Dark Energy Survey is a survey of 240000 emission-line galaxies in the distant Universe, measured with the AAOmega spectrograph on the 3.9-m Anglo-Australian Telescope (AAT). The primary aim of the survey is to precisely measure the scale of baryon acoustic oscillations (BAO) imprinted on the spatial distribution of these galaxies at l…
The dependence of Type Ia Supernovae luminosities on their host galaxies
Sullivan, M.; Lidman, C.; Astier, P. +22 more
Precision cosmology with Type Ia supernovae (SNe Ia) makes use of the fact that SN Ia luminosities depend on their light-curve shapes and colours. Using Supernova Legacy Survey (SNLS) and other data, we show that there is an additional dependence on the global characteristics of their host galaxies: events of the same light-curve shape and colour …
Detection of a dark substructure through gravitational imaging
Vegetti, S.; Treu, T.; Gavazzi, R. +2 more
We report the detection of a dark substructure - undetected in the Hubble Space Telescope HST ACS F814W image - in the gravitational lens galaxy SDSSJ0946+1006 (the `double Einstein ring'), through direct gravitational imaging. The detection of a small mass concentration in the surface density maps, at 4.3 kpc from the galaxy centre, has a strong …
Star formation rates and masses of z ~ 2 galaxies from multicolour photometry
Dickinson, Mark; Daddi, Emanuele; Maraston, Claudia +4 more
Fitting synthetic spectral energy distributions (SEDs) to the multiband photometry of galaxies to derive their star formation rates (SFRs), stellar masses, ages, etc. requires making a priori assumptions about their star formation histories (SFHs). A widely adopted parametrization of the SFH, the so-called τ models where SFR ~ e-t/τ is …
Accurate fundamental parameters for 23 bright solar-type stars
Butler, R. P.; Carrier, F.; Lo Curto, G. +7 more
We combine results from interferometry, asteroseismology and spectroscopy to determine accurate fundamental parameters of 23 bright solar-type stars, from spectral type F5 to K2 and luminosity classes III-V. For some stars we can use direct techniques to determine the mass, radius, luminosity and effective temperature, and we compare with indirect…
Galaxies at z = 6-9 from the WFC3/IR imaging of the Hubble Ultra Deep Field
McLure, R. J.; Dunlop, J. S.; Koekemoer, A. M. +5 more
We present the results of a systematic search for galaxies in the redshift range z = 6-9, within the new, deep, near-infrared (Y, J, H) imaging of the Hubble Ultra Deep Field provided by the Wide Field Camera 3 (WFC3) on the Hubble Space Telescope. We have performed full spectral energy distribution fitting to the optical+infrared photometry of al…
Broad iron L line and X-ray reverberation in 1H0707-495
Ponti, G.; Fabian, A. C.; Miller, J. M. +5 more
A detailed analysis of a long XMM-Newton observation of the narrow-line type 1 Seyfert galaxy 1H0707-495 is presented, including spectral fitting, spectral variability and timing studies. The two main features in the spectrum are the drop at ~7keV and a complex excess below 1keV. These are well described by two broad, K and L, iron lines. Alternat…
The contribution of high-redshift galaxies to cosmic reionization: new results from deep WFC3 imaging of the Hubble Ultra Deep Field
Bunker, Andrew J.; Stark, Daniel P.; Ellis, Richard S. +6 more
We have searched for star-forming galaxies at z ~ 7-10 by applying the Lyman-break technique to newly released Y-, J- and H-band images (1.1, 1.25 and 1.6µm) from Wide Field Camera 3 (WFC3) on the Hubble Space Telescope. By comparing these images of the Hubble Ultra Deep Field with the Advanced Camera for Surveys (ACS) z'-band (0.85µm)…