Search Publications
Quantitative spectroscopy of B-type supergiants
Butler, K.; Weßmayer, D.; Przybilla, N.
Context. B-type supergiants are versatile tools to address a number of highly-relevant astrophysical topics, ranging from stellar atmospheres over stellar and galactic evolution to the characterisation of interstellar sightlines and to the cosmic distance scale.
Aims: A hybrid non-local thermodynamic equilibrium (LTE) approach, involving line…
Coronal mass ejection followed by a prominence eruption and a plasma blob as observed by Solar Orbiter
Heinzel, P.; Mierla, M.; Zhukov, A. N. +26 more
Context. On 2021 February 12, two subsequent eruptions occurred above the western limb of the Sun, as seen along the Sun-Earth line. The first event was a typical slow coronal mass ejection (CME), followed ∼7 h later by a smaller and collimated prominence eruption, originating south of the CME, followed by a plasma blob. These events were observed…
First direct dynamical detection of a dual supermassive black hole system at sub-kiloparsec separation
Pechetti, Renuka; Neumayer, Nadine; Seth, Anil C. +7 more
We investigated whether the two recently discovered nuclei in NGC 7727 both host a super-massive black hole (SMBH). We used the high spatial resolution mode of the integral-field spectrograph MUSE on the VLT in adaptive optics mode to resolve the stellar kinematics within the sphere of influence of both putative black holes. We combined the kinema…
Do radio active galactic nuclei reflect X-ray binary spectral states?
Guainazzi, Matteo; Moravec, Emily; Panessa, Francesca +5 more
Context. Over recent years there has been mounting evidence that accreting supermassive black holes in active galactic nuclei (AGNs) and stellar mass black holes have similar observational signatures: thermal emission from the accretion disk, X-ray coronas, and relativistic jets. Further, there have been investigations into whether or not AGNs hav…
Constraining quasar structure using high-frequency microlensing variations and continuum reverberation
Courbin, F.; Sluse, D.; Millon, M. +4 more
Gravitational microlensing is a powerful tool for probing the inner structure of strongly lensed quasars and for constraining parameters of the stellar mass function of lens galaxies. This is achieved by analysing microlensing light curves between the multiple images of strongly lensed quasars and accounting for the effects of three main variable …
H2CS deuteration maps towards the pre-stellar core L1544
Eisenhauer, F.; Fuente, A.; Caselli, P. +7 more
Context. Deuteration is a crucial tool for understanding the complexity of interstellar chemical processes, especially when they involve the interplay of gas-phase and grain-surface chemistry. In the case of multiple deuteration, comparing observation with the results of chemical modelling is particularly effective to study how molecules are inher…
The dawn of a new era for dustless HdC stars with Gaia eDR3
Kasliwal, M. M.; Karambelkar, V.; Tisserand, P. +7 more
Context. Decades after their discovery, only four hydrogen-deficient carbon (HdC) stars were known to have no circumstellar dust shell. This is in complete contrast to the ∼130 known Galactic HdC stars that are notorious for being heavy dust producers, that is the R Coronae Borealis (RCB) stars. Together, they form a rare class of supergiant stars…
X-ray studies of the Abell 3158 galaxy cluster with eROSITA
Pacaud, F.; Ramos-Ceja, M. E.; Bulbul, E. +13 more
Context. The most nearby clusters are the best places for studying physical and enrichment effects in the faint cluster outskirts. The Abell 3158 cluster (A3158), located at z = 0.059, is quite extended with a characteristic radius r200 = 23.95 arcmin. The metal distribution in the outskirts of this cluster has previously been studied w…
Stellar population of the Rosette Nebula and NGC 2244. Application of the probabilistic random forest
Peña Ramírez, K.; Bouy, H.; Krone-Martins, A. +5 more
Context. Measurements of internal dynamics of young clusters and star-forming regions are crucial to fully understand the process of their formation. A basic prerequisite for this is a well-established and robust list of probable members.
Aims: In this work, we study the 2.8° ×2.6° region in the emblematic Rosette Nebula, centred in the young…
Flares and rotation of M dwarfs with habitable zones accessible to TESS planet detections
Stelzer, B.; Raetz, St.; Magaudda, E. +1 more
Context. More than 4000 exoplanets have been discovered to date, providing the search for a place capable of hosting life with a large number of targets. With the Transiting Exoplanet Survey Satellite (TESS) having completed its primary mission in July 2020, the number of planets confirmed by follow-up observations is growing further. Crucial for …