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Moonlets wandering on a leash-ring
Spahn, F.; Winter, O. C.; Mourão, D. C. +2 more
Since the Voyager flybys, embedded moonlets have been proposed to explain some of the surprising structures observed in Saturn's narrow F ring. Experiments conducted with the Cassini spacecraft support this suggestion. Images of the F ring show bright compact spots, and seven occultations of stars by the F ring, monitored by ultraviolet and infrar…
SuperWASP-North extrasolar planet candidates between 3h < RA < 6h
Hodgkin, S. T.; Lister, T. A.; Christian, D. J. +21 more
The Wide Angle Search for Planets (WASP) photometrically surveys a large number of nearby stars to uncover candidate extrasolar planet systems by virtue of small-amplitude light curve dips on a <~5-d time-scale typical of the `Hot-Jupiters'. Observations with the SuperWASP-North instrument between 2004 April and September produced a rich photom…
Estimating stellar parameters from spectra using a hierarchical Bayesian approach
Aerts, C.; Decin, L.; Molenberghs, G. +1 more
A method is developed for fitting theoretically predicted astronomical spectra to an observed spectrum. Using a hierarchical Bayesian principle, the method takes both systematic and statistical measurement errors into account, which has not been done before in the astronomical literature. The goal is to estimate fundamental stellar parameters and …
VLT/SINFONI integral field spectroscopy of the Super-antennae
Ivanov, V. D.; Reunanen, J.; Tacconi-Garman, L. E.
We present the results of H- and K-band very large telescope/Spectrograph for INtegral Field Observations in the Near Infrared (VLT/SINFONI) integral field spectroscopy of the Ultraluminous Infrared Galaxy (ULIRG) IRAS 19254-7245 (the Super-antennae), an interacting double galaxy system containing an embedded active galactic nuclei. Deep K-band sp…
Broad-band X-ray spectrum of the newly discovered broad-line radio galaxy IGR J21247+5058
de Rosa, A.; Giroletti, M.; Bird, A. J. +7 more
In this paper, we present radio and high-energy observations of the INTEGRAL source IGR J21247+5058, a broad line emitting galaxy obscured by the Galactic plane. Archival Very Large Array radio data indicate that IGR J21247+5058 can be classified as an Faranoff-Riley type II Broad-Line Radio Galaxy. The spectrum between 610 MHz and 15 GHz is typic…
Hidden activity in high-redshift spheroidal galaxies from mid-infrared and X-ray observations in the GOODS-North field
Rodighiero, G.; Fritz, J.; Franceschini, A. +6 more
We exploit very deep mid-infrared (MIR) and X-ray observations by Spitzer and Chandra in the GOODS-North field to identify signs of hidden [either starburst or active galactic nucleus (AGN)] activity in spheroidal galaxies between z ~= 0.3 and 1. Our reference is a complete sample of 168 morphologically classified spheroidal (elliptical/lenticular…
Radio emission from the Sy 1.5 galaxy NGC 5033
Alberdi, A.; Pérez-Torres, M. A.
We present new continuum VLA observations of the nearby Sy 1.5 galaxy NGC 5033, made at 4.9 and 8.4 GHz on 2003 April 8. Combined with VLA archival observations at 1.4- and 4.9-GHz made on 1993 August 7, 1999 August 29 and 1999 October 31, we sample the galaxy radio emission at scales ranging from the nuclear regions (<~100 pc) to the outer reg…
Further observations of Hipparcos red stars and standards for UBV(RI)C photometry
Kilkenny, D.; Marang, F.; Koen, C. +2 more
We present homogeneous and standardized UBV(RI)C JHK photometry for over 100 M stars selected from an earlier paper on the basis of apparent photometric constancy. L photometry has been obtained for stars brighter than about L = 6. Most of the stars have a substantial number of UBV(RI)C observations and, it is hoped, will pro…
The use of genetic algorithms to model protoplanetary discs
Hetem, Annibal; Gregorio-Hetem, Jane
The protoplanetary discs of T Tauri and Herbig Ae/Be stars have previously been studied using geometric disc models to fit their spectral energy distribution (SED). The simulations provide a means to reproduce the signatures of various circumstellar structures, which are related to different levels of infrared excess. With the aim of improving our…
Ionized and neutral gas in the peculiar star/cluster complex in NGC 6946
Larsen, S.; Bastian, N.; Afanasiev, V. L. +8 more
The characteristics of ionized and H I gas in the peculiar star/cluster complex in NGC 6946, obtained with the 6-m telescope (BTA) Special Astrophysical Observatory Russian Academy of Sciences (RAS), the Gemini North telescope, and the Westerbork Synthesis Radio Telescope, are presented. The complex is unusual as hosting a super star cluster, the …