Search Publications
Discovery and mass measurement of the hot, transiting, Earth-sized planet, GJ 3929 b
Amado, P. J.; Caballero, J. A.; Pallé, E. +64 more
We report the discovery of GJ 3929 b, a hot Earth-sized planet orbiting the nearby M3.5 V dwarf star, GJ 3929 (G 180-18, TOI-2013). Joint modelling of photometric observations from TESS sectors 24 and 25 together with 73 spectroscopic observations from CARMENES and follow-up transit observations from SAINT-EX, LCOGT, and OSN yields a planet radius…
A machine-learning photometric classifier for massive stars in nearby galaxies. I. The method
Yang, Ming; Bonanos, Alceste Z.; Maravelias, Grigoris +3 more
Context. Mass loss is a key parameter in the evolution of massive stars. Despite the recent progress in the theoretical understanding of how stars lose mass, discrepancies between theory and observations still hold. Moreover, episodic mass loss in evolved massive stars is not included in models, and the importance of its role in the evolution of m…
The stable climate of KELT-9b
Alonso, R.; Deleuil, M.; Erikson, A. +76 more
Even among the most irradiated gas giants, so-called ultra-hot Jupiters, KELT-9b stands out as the hottest planet thus far discovered with a dayside temperature of over 4500 K. At these extreme irradiation levels, we expect an increase in heat redistribution efficiency and a low Bond albedo owed to an extended atmosphere with molecular hydrogen di…
Hot Jupiters, cold kinematics. High phase space densities of host stars reflect an age bias
Mustill, Alexander J.; Davies, Melvyn B.; Lambrechts, Michiel
Context. The birth environments of planetary systems are thought to influence planet formation and orbital evolution through external photoevaporation and stellar flybys. Recent work has claimed observational support for this, in the form of a correlation between the properties of planetary systems and the local Galactic phase space density of the…
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…