Search Publications
Studying the asymmetry of the globular cluster population of NGC 4261
Zezas, A.; Wolter, A.; O'Sullivan, E. +5 more
We present an analysis of the globular cluster (GC) population of the elliptical galaxy NGC 4261 based on Hubble Space Telescope Wide Field Planetary Camera 2 data in the B, V and I bands. We study the spatial distribution of the GCs in order to probe the anisotropy in the azimuthal distribution of the discrete X-ray sources in the galaxy revealed…
Electron optical depths and temperatures of symbiotic nebulae from Thomson scattering
Skopal, A.; Sekeráš, M.
Symbiotic binaries are comprised of nebulae, whose densest portions have electron concentrations of 108-1012 cm-3 and extend to a few astronomical units. They are optically thick enough to cause a measurable effect of the scattering of photons on free electrons. In this paper, we model the extended wings of strong …
Herschel-ATLAS/GAMA: spatial clustering of low-redshift submm galaxies
Rodighiero, G.; Valtchanov, I.; Ivison, R. J. +44 more
We have measured the clustering properties of low-redshift (z < 0.3) submm galaxies detected at 250 µm in the Herschel-ATLAS science demonstration phase field. We selected a sample for which we have high-quality spectroscopic redshifts, obtained from reliably matching the 250-µm sources to a complete (for r < 19.4) sample of gala…
Evidence of merging in the Seyfert galaxy NGC 3393, revealed by modelling the spectra
Contini, M.
The discovery (Fabbiano et al. 2001) of two active black holes in the Seyfert galaxy NGC 3393, which are separated by about 490 light years, has revealed a merging event. This has led us to look for other evidence of galaxy collision and merging, using an analysis of the observed spectra in different frequency ranges. In the narrow-line region (NL…
Parametrization effects in the analysis of AMI Sunyaev-Zel'dovich observations
AMI Consortium; Olamaie, Malak; Rodríguez-Gonzálvez, Carmen +16 more
Most Sunyaev-Zel'dovich (SZ) and X-ray analyses of galaxy clusters try to constrain the cluster total mass (MT(r)) and/or gas mass (Mg(r)) using parametrized models derived from both simulations and imaging observations, and assumptions of spherical symmetry and hydrostatic equilibrium. By numerically exploring the probabilit…
The unseen population of F- to K-type companions to hot subdwarf stars
Gänsicke, B. T.; Heber, U.; Breedt, E. +6 more
We present a method to select hot subdwarf stars with A- to M-type companions using photometric selection criteria. We cover a wide range in wavelength by combining Galaxy Evolution Explorer (GALEX) ultraviolet data, optical photometry from the Sloan Digital Sky Survey (SDSS) and the Carlsberg Meridian Telescope, near-infrared data from Two-Micron…
The structures of distant galaxies - V. The evolution of galaxy structure in stellar mass at z<1
Conselice, C. J.; Lanyon-Foster, M. M.; Merrifield, M. R.
The structure and morphology of a galaxy are nearly always studied using the light originating from stars; however, ideally one is interested in measuring structure using the stellar mass distribution. Not only does stellar mass trace out the underlying distribution of matter, it also minimizes the effects of star formation and dust on the appeara…
Spatial matter density mapping of the STAGES Abell A901/2 supercluster field with 3D lensing
Simon, P.; Heymans, C.; Schrabback, T. +13 more
We present weak lensing data from the Hubble Space Telescope(HST)/Space Telescope A901/902 Galaxy Evolution Survey (STAGES) survey to study the three-dimensional spatial distribution of matter and galaxies in the Abell 901/902 supercluster complex. Our method improves over the existing 3D lensing mapping techniques by calibrating and removing reds…
Atomic hydrogen, star formation and feedback in the lowest mass blue compact dwarf galaxies
Chiboucas, Kristin; Tully, R. Brent; Karachentsev, Igor D. +3 more
We present the results from a search for H I emission from a sample of newly discovered dwarf galaxies in the M81 group. H I is detected in three galaxies, all of which are classified as blue compact dwarf galaxies (BCDs). The H I masses of these galaxies are ∼106 M⊙, making them some of the lowest mass BCDs known. For these …
Orbit determination of close binary systems using lucky imaging
Rica, F. M.; Barrena, R.; Vázquez, G. +2 more
We present relative positions of visual binaries observed in 2009 with the FastCam 'lucky-imaging' camera mounted on the 1.5-m Carlos Sánchez Telescope at the Observatorio del Teide. We obtained 424 CCD observations (averaged in 198 mean relative positions) of 157 binaries with angular separations in the range 0.14-15.40 arcsec, with a median sepa…