Search Publications
The properties of (sub-)millimetre-selected galaxies as revealed by CANDELS HST WFC3/IR imaging in GOODS-South
Kartaltepe, J. S.; Ferguson, H. C.; McLure, R. J. +16 more
We have exploited the Hubble Space Telescope (HST) Cosmic Assembly Near-IR Deep Extragalactic Legacy Survey (CANDELS) J and H-band Wide Field Camera 3 (WFC3)/infrared (IR) imaging to study the properties of (sub-)millimetre galaxies within the Great Observatories Origins Deep Survey South (GOODS-South) field. After using the deep radio (Very Large…
New image statistics for detecting disturbed galaxy morphologies at high redshift
Koekemoer, A. M.; Lotz, J. M.; Conselice, C. J. +5 more
Testing theories of hierarchical structure formation requires estimating the distribution of galaxy morphologies and its change with redshift. One aspect of this investigation involves identifying galaxies with disturbed morphologies (e.g. merging galaxies). This is often done by summarizing galaxy images using, e.g. the concentration, asymmetry a…
Flux calibration of broad-band far-infrared and submillimetre photometric instruments: theory and application to Herschel-SPIRE
Valtchanov, I.; Bock, J.; Conley, A. +15 more
Photometric instruments operating at far-infrared to millimetre wavelengths often have broad spectral passbands (λ/Δλ ∼ 3 or less), especially those operating in space. A broad passband can result in significant variation of the beam profile and aperture efficiency across the passband, effects which thus far have not generally been taken into acco…
The binary fractions in the massive young Large Magellanic Cloud star clusters NGC 1805 and NGC 1818
Deng, Licai; de Grijs, Richard; Li, Chengyuan
Using high-resolution data sets obtained with the Hubble Space Telescope, we investigate the radial distributions of the F-type main-sequence binary fractions in the massive young Large Magellanic Cloud star clusters NGC 1805 and NGC 1818. We apply both an isochrone-fitting approach and χ2 minimization using Monte Carlo simulations, for…
A blurred reflection interpretation for the intermediate flux state in Mrk 335
Fabian, A. C.; Komossa, S.; Miniutti, G. +7 more
As part of a long-term monitoring campaign of Mrk 335, deep XMM-Newton observations catch the narrow-line Seyfert 1 galaxy (NLS1) in a complex, intermediate flux interval as the active galaxy is transiting from low to high flux. Other works on these same data examined the general behaviour of the NLS1 and the conditions of its warm absorber. The a…
The insignificance of Major mergers in driving star formation at z =~ 2.
O'Connell, R. W.; Dekel, A.; Hathi, N. P. +7 more
We study the significance of major-merger-driven star formation in the early Universe, by quantifying the contribution of this process to the total star formation budget in 80 massive (M* > 1010 M⊙) galaxies at z ≃ 2. Employing visually classified morphologies from rest-frame V-band Hubble Space Telescope (HST) …
Cosmological constraints from baryon acoustic oscillations and clustering of large-scale structure
Halpern, M.; Hinshaw, G.; Addison, G. E.
We constrain cosmological parameters using combined measurements of the baryon acoustic oscillation (BAO) feature in the correlation function of galaxies and Lyα absorbers that together cover 0.1 < z < 2.4. The BAO position measurements alone - without fixing the absolute sound horizon `standard ruler' length with cosmic microwave background…
Hard-X-ray spectra of active galactic nuclei in the INTEGRAL complete sample
Bird, A. J.; Ubertini, P.; Malizia, A. +4 more
In this paper, we present the hard-X-ray spectral analysis of a complete sample of active galactic nuclei (AGNs) detected by INTEGRAL/IBIS. In conjunction with IBIS spectra, we make use of Swift/BAT data, with the aim of cross-calibrating the two instruments, studying source variability and constraining some important spectral parameters. We find …
Fast and slow rotators in the densest environments: a FLAMES/GIRAFFE integral field spectroscopy study of galaxies in A1689 at z = 0.183
Dalla Bontà, E.; Davies, R. L.; D'Eugenio, F. +1 more
We present FLAMES/GIRAFFE integral field spectroscopy of 30 galaxies in the massive cluster A1689 at z = 0.183. Conducting an analysis similar to that of ATLAS3D, we extend the baseline of the kinematic morphology-density relation by an order of magnitude in projected density and show that it is possible to use existing instruments to i…
The accretion flow to the intermittent accreting millisecond pulsar, HETE J1900.1-2455, as observed by XMM-Newton and RXTE
Egron, E.; Papitto, A.; Di Salvo, T. +6 more
We present a study of the accretion flow to the intermittent accreting millisecond pulsar, HETE J1900.1-2455, based on observations made simultaneously by XMM-Newton and RXTE. The 0.33-50 keV energy spectrum is described by the sum of a hard Comptonized component produced in an optically thin τ ≃ 1 corona, a soft thermal kTin ≃ 0.2 keV …