Search Publications
Carbon dust in the evolved born-again planetary nebulae A 30 and A 78
Estrada-Dorado, S.; Guerrero, M. A.; Toalá, J. A. +6 more
We present an infrared (IR) characterization of the born-again planetary nebulae (PNe) A 30 and A 78 using IR images and spectra. We demonstrate that the carbon-rich dust in A 30 and A 78 is spatially coincident with the H-poor ejecta and coexists with hot X-ray-emitting gas up to distances of 50 arcsec from the central stars of PNe (CSPNe). Dust …
The effect of varying porosity and inhomogeneities of the surface dust layer on the modelling of comet gas production
Skorov, Yuri; Reshetnyk, Volodymyr; Blum, Jürgen +3 more
We study how uncertainties in knowledge of the microstructure of the porous dust surface layer affect our estimates of effective gas production of comet 67P/Churyumov-Gerasimenko. We analyse the transport properties (distribution of free paths, mean pore size, permeability) for random densely packed porous layers. Bimodal layers, as well as variou…
Asteroseismology of overmassive, undermassive, and potential past members of the open cluster NGC 6791
Miglio, A.; Brogaard, K.; Arentoft, T. +1 more
We perform an asteroseismic investigation of giant stars in the field of NGC 6791 with previous indications of atypical evolution. The analysis uses observations from Kepler and Gaia in combination with ground-based photometry, a literature radial-velocity study, and measurements of eclipsing binaries in the cluster. We derive mass, radius, effect…
The eclipsing binary systems with δ Scuti component - I. KIC 10661783
Daszyńska-Daszkiewicz, J.; Szewczuk, W.; Miszuda, A.
We present a comprehensive study of the eclipsing binary system KIC 10661783. The analysis of the whole Kepler light curve, corrected for the binary effects, reveals a rich oscillation spectrum with 590 significant frequency peaks, 207 of which are independent. In addition to typical δ Scuti (δ Sct) frequencies, we find small-amplitude signals in …
MUSE-ALMA haloes VI: coupling atomic, ionized, and molecular gas kinematics of galaxies
Hamanowicz, Aleksandra; Péroux, Céline; Augustin, Ramona +7 more
We present results of MUSE-ALMA haloes, an ongoing study of the circumgalactic medium (CGM) of galaxies (z ≤ 1.4). Using multiphase observations we probe the neutral, ionized, and molecular gas in a subsample containing six absorbers and nine associated galaxies in the redshift range z ~ 0.3-0.75. Here, we give an in-depth analysis of the newly CO…
A faint companion around CrA-9: protoplanet or obscured binary?
Lodato, G.; Pinte, C.; Casassus, S. +16 more
Understanding how giant planets form requires observational input from directly imaged protoplanets. We used VLT/NACO and VLT/SPHERE to search for companions in the transition disc of 2MASS J19005804-3645048 (hereafter CrA-9), an accreting M0.75 dwarf with an estimated age of 1-2 Myr. We found a faint point source at ∼0.7-arcsec separation from Cr…
AU-scale radio imaging of the wind collision region in the brightest and most luminous non-thermal colliding wind binary Apep
Callingham, J. R.; Marcote, B.; De Becker, M. +5 more
The recently discovered colliding-wind binary (CWB) Apep has been shown to emit luminously from radio to X-rays, with the emission driven by a binary composed of two Wolf-Rayet (WR) stars of one carbon-sequence (WC8) and one nitrogen-sequence (WN4-6b). Mid-infrared imaging revealed a giant spiral dust plume that is reminiscent of a pinwheel nebula…
Reconciling galaxy cluster shapes, measured by theorists versus observers
Massey, Richard; Rhodes, Jason; Jauzac, Mathilde +4 more
If properly calibrated, the shapes of galaxy clusters can be used to investigate many physical processes: from feedback and quenching of star formation, to the nature of dark matter. Theorists frequently measure shapes using moments of inertia of simulated particles'. We instead create mock (optical, X-ray, strong-, and weak-lensing) observations …
Mass-loss law for red giant stars in simple population globular clusters
Milone, A. P.; Cordoni, G.; Marino, A. F. +12 more
The amount of mass lost by stars during the red-giant branch (RGB) phase is one of the main parameters to understand and correctly model the late stages of stellar evolution. Nevertheless, a fully comprehensive knowledge of the RGB mass-loss is still missing. Galactic Globular Clusters (GCs) are ideal targets to derive empirical formulations of ma…
Ultra-compact dwarfs beyond the centre of the Fornax galaxy cluster: hints of UCD formation in low-density environments
Janz, Joachim; Mieske, Steffen; Peletier, Reynier F. +6 more
Ultra-compact dwarf galaxies (UCDs) were serendipitously discovered by spectroscopic surveys in the Fornax cluster 20 yr ago. Nowadays, it is commonly accepted that many bright UCDs are the nuclei of galaxies that have been stripped. However, this conclusion might be driven by biased samples of UCDs in high-density environments, on which most sear…