Search Publications
Discovery of the benchmark metal-poor T8 dwarf BD +01° 2920B
Marocco, F.; Homeier, D.; Pinfield, D. J. +20 more
We have searched the Wide-field Infrared Survey Explorer first data release for widely separated (≤10 000 au) late T dwarf companions to Hipparcos and Gliese stars. We have discovered a new binary system containing a K-band suppressed T8p dwarf WISEP J142320.86+011638.1 and the mildly metal poor ([Fe/H] =-0.38 ± 0.06) primary BD +01° 2920 (HIP 703…
HerMES: point source catalogues from deep Herschel-SPIRE observations
Pérez-Fournon, I.; Rodighiero, G.; Valtchanov, I. +38 more
We describe the generation of single-band point source catalogues from submillimetre Herschel-SPIRE observations taken as part of the Science Demonstration Phase of the Herschel Multi-tiered Extragalactic Survey (HerMES). Flux densities are found by means of peak finding and the fitting of a Gaussian point-response function. With highly confused i…
Wide-field imaging of NGC 4365's globular cluster system: the third subpopulation revisited
Spitler, Lee R.; Forbes, Duncan A.; Blom, Christina
Analysis of the globular cluster (GC) system of the giant elliptical (E3) galaxy NGC 4365, from eight Hubble Space Telescope/Advanced Camera for Surveys pointings and a wide-field Subaru/Suprime-Cam image, is presented. Using magnitude, colour and size criteria, we obtain a catalogue of GC candidates. We also measure the photometric properties of …
Nuclear star clusters and the stellar spheroids of their host galaxies
Böker, Torsten; Knigge, Christian; Leigh, Nathan
We combine published photometry for the nuclear star clusters (NSCs) and stellar spheroids of 51 low-mass, early-type galaxies in the Virgo cluster with empirical mass-to-light ratios, in order to complement previous studies that explore the dependence of NSC masses on various properties of their host galaxies. We confirm a roughly linear relation…
The cosmological analysis of X-ray cluster surveys - II. Application of the CR-HR method to the XMM archive
Altieri, B.; Valtchanov, I.; Pierre, M. +5 more
We have processed 2774 high galactic observations from the XMM archive (as of 2010 May) and extracted a serendipitous catalogue of some 850 clusters of galaxies based on purely X-ray criteria, following the methodology developed for the XMM-Large-Scale Survey. Restricting the sample to the highest signal-to-noise ratio objects (347 clusters), we p…
The star formation history and dust content in the far outer disc of M31
Lewis, Geraint F.; McConnachie, Alan W.; Ibata, Rodrigo A. +7 more
We present a detailed analysis of two fields located 26 kpc (∼5 radial scalelengths) from the centre of M31 along the south-west semimajor axis of the disc. One field samples the major axis populations - the Outer Disc field - while the other is offset by ∼18 arcmin and samples the warp in the stellar disc - the warp field. The colour-magnitude di…
Triggered star formation in the inner filament of Centaurus A
Mutchler, Max; Whitmore, Bradley C.; Shabala, Stanislav S. +7 more
We present recent Hubble Space Telescope observations of the inner filament of Centaurus A, using the new Wide Field Camera 3 (WFC3) F225W, F657N and F814W filters. We find a young stellar population near the south-west tip of the filament. Combining the WFC3 data set with archival Advanced Camera for Surveys (ACS) F606W observations, we are able …
The G305 star-forming complex: the central star clusters Danks 1 and Danks 2
Kudritzki, Rolf-Peter; Figer, Donald F.; Clark, J. S. +7 more
The G305 H II complex (G305.4+0.1) is one of the most massive star-forming structures yet identified within the Galaxy. It is host to many massive stars at all stages of formation and evolution, from embedded molecular cores to post-main-sequence stars. Here, we present a detailed near-infrared analysis of the two central star clusters Danks 1 and…
A newly discovered young massive star cluster at the far end of the Galactic Bar
Figer, Donald F.; Davies, Ben; Najarro, Francisco +4 more
We present a near-infrared study of the candidate star cluster Mercer 81, located at the centre of the G338.4+0.1 H II region and close to the TeV gamma-ray source HESS 1640-465. Using Hubble Space Telescope/NICMOS imaging and VLT/ISAAC spectroscopy, we have detected a compact and highly reddened cluster of stars, although the bright stars in the …
Broad-band study of hard X-ray-selected absorbed active galactic nuclei
de Rosa, A.; Ubertini, P.; Landi, R. +6 more
In this paper we report on the broad-band X-ray properties of a complete sample of absorbed Seyfert galaxies hard X-ray selected with INTEGRAL. Our sample is composed of 33 sources, of which 15 are newly discovered active galactic nuclei (AGN) above 20 keV (IGR sources), while 18 are already known type 2 AGN ('known'). For 17 sources (15 IGR + 2 '…