Search Publications
Constraints on the structure of hot exozodiacal dust belts
Kirchschlager, Florian; Krivov, Alexander V.; Wolf, Sebastian +2 more
Recent interferometric surveys of nearby main-sequence stars show a faint but significant near-infrared excess in roughly two dozen systems, I.e. around 10-30 per cent of stars surveyed. This excess is attributed to dust located in the immediate vicinity of the star, the origin of which is highly debated. We used previously published interferometr…
Near-infrared variability study of the central 2.3 × 2.3 arcmin2 of the Galactic Centre - II. Identification of RR Lyrae stars in the Milky Way nuclear star cluster
Morris, Mark R.; Williams, Benjamin F.; Rich, R. Michael +8 more
Because of strong and spatially highly variable interstellar extinction and extreme source crowding, the faint (K ≥ 15) stellar population in the Milky Way's nuclear star cluster is still poorly studied. RR Lyrae stars provide us with a tool to estimate the mass of the oldest, relative dim stellar population. Recently, we analysed <italic>&l…
Asteroseismic masses of retired planet-hosting A-stars using SONG
Huber, Daniel; Bedding, Timothy R.; Stello, Dennis +9 more
To better understand how planets form, it is important to study planet occurrence rates as a function of stellar mass. However, estimating masses of field stars is often difficult. Over the past decade, a controversy has arisen about the inferred occurrence rate of gas-giant planets around evolved intermediate-mass stars - the so-called 'retired A…
The merger remnant NGC 3610 and its globular cluster system: a large-scale study
Bassino, Lilia P.; Caso, Juan P.
We present a photometric study of the prototype merger remnant NGC 3610 and its globular cluster (GC) system, based on new Gemini/GMOS and Advanced Camera for Surveys/Hubble Space Telescope archival images. Thanks to the large field of view of our GMOS data, larger than previous studies, we are able to detect a 'classical' bimodal GC colour distri…
Extremely late photometry of the nearby SN 2011fe
Spyromilio, J.; Fransson, C.; Jerkstrand, A. +6 more
Type Ia supernovae are widely accepted to be the outcomes of thermonuclear explosions in white dwarf stars. However, many details of these explosions remain uncertain (e.g. the mass, ignition mechanism and flame speed). Theory predicts that at very late times (beyond 1000 d) it might be possible to distinguish between explosion models. Few very ne…
Quantifying the (X/peanut)-shaped structure of the Milky Way - new constraints on the bar geometry
Ciambur, Bogdan C.; Bland-Hawthorn, Joss; Graham, Alister W.
The nature, size and orientation of the Milky Way's bar and `bulge' have been the subject of conflicting interpretations in the literature. Here, we present a novel approach to inferring the properties of the long bar, which extends beyond the inner `bulge', by using information encoded in the Galaxy's X/peanut (X/P)-shaped structure. We perform a…
What planetary nebulae can tell us about jets in core collapse supernovae
Soker, Noam; Bear, Ealeal
We compare the morphology of the core collapse supernova remnant (CCSNR) W49B with the morphology of many planetary nebulae (PNe), and deduce the orientation of the jets that shaped this CCSNR and estimate their energy. We find morphological features that are shared by some PNe and by the CCSNR W49B. In PNe these features, such as a barrel-shaped …
The dust environment of comet 67P/Churyumov-Gerasimenko: results from Monte Carlo dust tail modelling applied to a large ground-based observation data set
Della Corte, Vincenzo; Lara, Luisa M.; Moreno, Fernando +6 more
We present an extensive data set of ground-based observations and models of the dust environment of comet 67P/Churyumov-Gerasimenko covering a large portion of the orbital arc from about 4.5 au pre-perihelion through 3.0 au post-perihelion, acquired during the current orbit. In addition, we have also applied the model to a dust trail image acquire…
Dynamical histories of the IC 348 and NGC 1333 star-forming regions in Perseus
Parker, Richard J.; Alves de Oliveira, Catarina
We present analyses of the spatial distributions of stars in the young (1-3 Myr) star-forming regions IC 348 and NGC 1333 in the Perseus giant molecular cloud. We quantify the spatial structure using the Q-parameter and find that both IC 348 and NGC 1333 are smooth and centrally concentrated with Q-parameters of 0.98 and 0.89, respectively. Neithe…
Large decay of X-ray flux in 2XMM J123103.2+110648: evidence for a tidal disruption event
Ho, Luis C.; Lin, Dacheng; Godet, Olivier +3 more
The X-ray source 2XMM J123103.2+110648 was previously found to show pure thermal X-ray spectra and an ∼3.8 h periodicity in three XMM-Newton X-ray observations in 2003-2005, and the optical spectrum of the host galaxy suggested it as a type 2 active galactic nucleus candidate. We have obtained new X-ray observations of the source, with Swift and C…