Search Publications
Cometary surface dust layers built out of millimetre-scale aggregates: dependence of modelled cometary gas production on the layer transport properties
Mottola, S.; Küppers, M.; Hartogh, P. +5 more
The standard approach to obtaining knowledge about the properties of the surface layer of a comet from observations of gas production consists of two stages. First, various thermophysical models are used to calculate gas production for a few sets of parameters. Second, a comparison of observations and theoretical predictions is performed. This app…
The orbital period versus absolute magnitude relationship of intermediate polars: implications for low states and outbursts
Mukai, Koji; Pretorius, Magaretha L.
Recent advances in time-domain astronomy have led to fresh observational insights into intermediate polars, a subtype of magnetic cataclysmic variables generally accreting via a partial accretion disc. These new discoveries include detections of superhumps, low states, and outbursts. However, these studies have largely relied on relative photometr…
C3PO: towards a complete census of co-moving pairs of stars - I. High precision stellar parameters for 250 stars
Bitsch, Bertram; Ting, Yuan-Sen; Dotter, Aaron +6 more
We conduct a line-by-line differential analysis of a sample of 125 co-moving pairs of stars (dwarfs and subgiants near solar metallicity). We obtain high-precision stellar parameters with average uncertainties in effective temperature, surface gravity, and metallicity of 16.5 K, 0.033 and 0.014 dex, respectively. We classify the co-moving pairs of…
LEMON: LEns MOdelling with Neural networks - I. Automated modelling of strong gravitational lenses with Bayesian Neural Networks
Koopmans, Léon V. E.; Li, Rui; Gentile, Fabrizio +4 more
The unprecedented number of gravitational lenses expected from new-generation facilities such as the ESA Euclid telescope and the Vera Rubin Observatory makes it crucial to rethink our classical approach to lens-modelling. In this paper, we present LEMON (Lens Modelling with Neural networks): a new machine-learning algorithm able to analyse hundre…
Peering into the central region of a nano-quasar: XMM-Newton and Chandra views of the CH Cyg symbiotic system
Toalá, J. A.; Sabin, L.; González-Martín, O. +3 more
We present the analysis of archival XMM-Newton and Chandra observations of CH Cyg, one of the most studied symbiotic stars (SySts). The combination of the high-resolution XMM-Newton RGS and Chandra HETG X-ray spectra allowed us to obtain reliable estimates of the chemical abundances and to corroborate the presence of multitemperature X-ray-emittin…
Optical polarization and spectral properties of the hydrogen-poor superluminous supernovae SN 2021bnw and SN 2021fpl
Pérez-Fournon, I.; Poidevin, F.; Omand, C. M. B. +6 more
New optical photometric, spectroscopic, and imaging polarimetry data are combined with publicly available data to study some of the physical properties of the two hydrogen-poor superluminous supernovae (SLSNe) SN 2021bnw and SN 2021fpl. For each SLSN, the best-fitting parameters obtained from the magnetar model with Modular Open-Source Fitter for …
Ironing the folds: the phase space chevrons of a GSE-like merger as a dark matter subhalo detector
Vasiliev, Eugene; Belokurov, Vasily; Evans, N. Wyn +2 more
Recent work uncovered features in the phase space of the Milky Way's stellar halo which may be attributed to the last major merger. When stellar material from a satellite is accreted onto its host, it phase mixes and appears finely substructured in phase space. For a high-eccentricity merger, this substructure most clearly manifests as numerous wr…
Chemical enrichment of the ICM within the virgo cluster - I. Radial profiles
Fabian, A. C.; Pinto, C.; Eckert, D. +8 more
We present a detailed analysis of the elemental abundances distribution of the Virgo cluster using XMM-Newton observations. We included in the analysis a new EPIC-pn energy scale calibration which allow us to measure velocities with uncertainties down to Δv ~150 km s-1. We investigate the radial distribution of O, Ne, Mg, Si, Ar, S, Ca,…
Nuclear activity in z < 0.3 QSO 2's mainly triggered by galaxy mergers
Storchi-Bergmann, Thaisa; Dall'Agnol de Oliveira, Bruno; Araujo, Bruna L. C. +2 more
We investigate the role of the close environment on the nuclear activity of a sample of 436 nearby (z < 0.3) QSO 2's - selected from SDSS-III spectra, via comparison of their environment and interaction parameters with those of a control sample of 1308 galaxies. We have used the corresponding SDSS images to obtain the number of neighbour galaxi…
The VISCACHA survey - VII. Assembly history of the Magellanic Bridge and SMC Wing from star clusters
Minniti, D.; Bica, E.; Barbuy, B. +15 more
The formation scenario of the Magellanic Bridge during an encounter between the Large and Small Magellanic Clouds ~200 Myr ago, as proposed by N-body models, would be imprinted in the chemical enrichment and kinematics of its stars and sites of ongoing star formation along its extension. We present an analysis of 33 Bridge star clusters using phot…