Search Publications
Characterizing the Galactic warp with Gaia - I. The tilted ring model with a twist
Figueras, Francesca; Mateu, Cecilia; Romero-Gómez, Mercè +2 more
We explore the possibility of detecting and characterizing the warp of the stellar disc of our Galaxy using synthetic Gaia data. The availability of proper motions and, for the brightest stars radial velocities, adds a new dimension to this study. A family of Great Circle Cell Counts methods is used. They are ideally suited to find the tilt and tw…
Optimal integrated abundances for chemical tagging of extragalactic globular clusters
Dotter, Aaron; Sakari, Charli M.; Shetrone, Matthew +2 more
High-resolution integrated light (IL) spectroscopy provides detailed abundances of distant globular clusters whose stars cannot be resolved. Abundance comparisons with other systems (e.g. for chemical tagging) require understanding the systematic offsets that can occur between clusters, such as those due to uncertainties in the underlying stellar …
Potential solar axion signatures in X-ray observations with the XMM-Newton observatory
Read, A. M.; Carter, J. A.; Sembay, S. +2 more
The soft X-ray flux produced by solar axions in the Earth's magnetic field is evaluated in the context of the European Space Agency's XMM-Newton observatory. Recent calculations of the scattering of axion-conversion X-rays suggest that the sunward magnetosphere could be an observable source of 0.2-10 keV photons. For XMM-Newton, any conversion X-r…
Multifrequency study of a new Fe-rich supernova remnant in the Large Magellanic Cloud, MCSNR J0508-6902
Haberl, F.; Filipović, M. D.; Ehle, M. +15 more
We present a detailed radio, X-ray and optical study of a newly discovered Large Magellanic Cloud (LMC) supernova remnant (SNR) which we denote as MCSNR J0508-6902. Observations from the Australia Telescope Compact Array (ATCA) and the XMM-Newton X-ray observatory are complemented by deep Hα images and Anglo-Australian Telescope AAOmega spectrosco…
Discovery of a transparent sightline at ρ ≲ 20 kpc from an interacting pair of galaxies
Johnson, Sean D.; Tripp, Todd M.; Prochaska, J. Xavier +3 more
We report the discovery of a transparent sightline at projected distances of ρ ≲ 20 kpc to an interacting pair of mature galaxies at z = 0.12. The sightline of the UV-bright quasar PG 1522+101 at zem = 1.328 passes at ρ = 11.5 kpc from the higher mass galaxy (M* = 1010.6 M⊙) and ρ = 20.4 kpc from the low…
Caught in the act: cluster `k+a' galaxies as a link between spirals and S0s
Rodríguez Del Pino, Bruno; Aragón-Salamanca, Alfonso; Balcells, Marc +3 more
We use integral field spectroscopy of 13 disc galaxies in the cluster AC114 at z ∼ 0.31 in an attempt to disentangle the physical processes responsible for the transformation of spiral galaxies in clusters. Our sample is selected to display a dominant young stellar population, as indicated by strong Hδ absorption lines in their integrated spectra.…
The HST/ACS Coma Cluster Survey - VII. Structure and assembly of massive galaxies in the centre of the Coma cluster
Mobasher, Bahram; Kormendy, John; Balcells, Marc +16 more
We constrain the assembly history of galaxies in the projected central 0.5 Mpc of the Coma cluster by performing structural decomposition on 69 massive (M⋆ ≥ 109 M⊙) galaxies using high-resolution F814W images from the Hubble Space Telescope (HST) Treasury Survey of Coma. Each galaxy is modelled with up to three Sé…
Optical spectra of five new Be/X-ray binaries in the Small Magellanic Cloud and the link of the supergiant B[e] star LHA 115-S 18 with an X-ray source
Hatzidimitriou, D.; Zezas, A.; Antoniou, V. +1 more
The Small Magellanic Cloud (SMC) is well known to harbour a large number of high-mass X-ray binaries (HMXBs). The identification of their optical counterparts provides information on the nature of the donor stars and can help to constrain the parameters of these systems and their evolution. We obtained optical spectra for a number of HMXBs identif…
HIP 3678: a hierarchical triple stellar system in the centre of the planetary nebula NGC 246
Mugrauer, M.; Adam, C.
We report the detection of a new low-mass stellar companion to the white dwarf HIP 3678 A, the central star of the planetary nebula NGC 246. The newly found companion is located about 1 arcsec (at projected separation of about 500 au) north-east of HIP 3678 A, and shares a common proper motion with the white dwarf and its known comoving companion …
Ultracompact dwarfs around NGC 3268
Richtler, Tom; Smith Castelli, Analía V.; Caso, Juan Pablo +2 more
We present radial velocities (from Gemini/GMOS) of the second sample of ultracompact dwarfs (UCDs) and bright globular clusters (GCs) in the Antlia cluster. 23 objects are located around the giant elliptical NGC 3268, and one is close to the fainter lenticular NGC 3273. Together with previously found UCDs around NGC 3258, a total of 35 UCDs and br…