Search Publications
Probing the atmosphere of WASP-69 b with low- and high-resolution transmission spectroscopy
Mallonn, M.; López-Puertas, M.; Nagel, E. +31 more
Consideration of both low- and high-resolution transmission spectroscopy is key for obtaining a comprehensive picture of exoplanet atmospheres. In studies of transmission spectra, the continuum information is well established with low-resolution spectra, while the shapes of individual lines are best constrained with high-resolution observations. I…
Solar prominence diagnostics from non-LTE modelling of Mg II h&k line profiles
Barczynski, K.; Schmieder, B.; Labrosse, N. +1 more
Aims: We investigate a new method to for obtaining the plasma parameters of solar prominences observed in the Mg II h&k spectral lines by comparing line profiles from the IRIS satellite to a bank of profiles computed with a one-dimensional non-local thermodynamic equilibrium (non-LTE) radiative transfer code.
Methods: Using a grid of…
The surface brightness-colour relations based on eclipsing binary stars and calibrated with Gaia EDR3
Kervella, P.; Anderson, R. I.; Maxted, P. F. L. +23 more
Aims: The surface brightness-colour relation (SBCR) is a basic tool for establishing precise and accurate distances within the Local Group. Detached eclipsing binary stars with accurately determined radii and trigonometric parallaxes allow calibration of the SBCRs with unprecedented accuracy.
Methods: We analysed four nearby eclipsing bi…
First near-relativistic solar electron events observed by EPD onboard Solar Orbiter
Fedorov, A.; Kulkarni, S. R.; Lario, D. +61 more
Context. Solar Orbiter, launched in February 2020, started its cruise phase in June 2020, in coincidence with its first perihelion at 0.51 au from the Sun. The in situ instruments onboard, including the Energetic Particle Detector (EPD), operate continuously during the cruise phase enabling the observation of solar energetic particles.
Aims: …
GW190814 follow-up with the optical telescope MeerLICHT
Vreeswijk, P. M.; Groot, P. J.; Bloemen, S. +8 more
Context. The Advanced LIGO and Virgo gravitational wave observatories detected a signal on 2019 August 14 during their third observing run, named GW190814. A large number of electromagnetic facilities conducted follow-up campaigns in the search for a possible counterpart to the gravitational wave event, which was made especially promising given th…
Inspecting the Cepheid parallax of pulsation using Gaia EDR3 parallaxes. Projection factor and period-luminosity and period-radius relations
Kervella, P.; Trahin, B.; Mérand, A. +5 more
Context. As primary anchors of the distance scale, Cepheid stars play a crucial role in our understanding of the distance scale of the Universe because of their period-luminosity relation. Determining precise and consistent parameters (radius, temperature, color excess, and projection factor) of Cepheid pulsating stars is therefore very important.…
The EXTraS project: Exploring the X-ray transient and variable sky
Salvaterra, R.; Haberl, F.; Greiner, J. +29 more
Temporal variability in flux and spectral shape is ubiquitous in the X-ray sky and carries crucial information about the nature and emission physics of the sources. The EPIC instrument on board the XMM-Newton observatory is the most powerful tool for studying variability even in faint sources. Each day, it collects a large amount of information ab…
Discovery of a recurrent spectral evolutionary cycle in the ultra-luminous X-ray sources Holmberg II X-1 and NGC 5204 X-1
Vasilopoulos, G.; Godet, O.; Webb, N. A. +2 more
Context. Most ultra-luminous X-ray sources (ULXs) are now thought to be powered by stellar-mass compact objects accreting at super-Eddington rates. While the discovery of evolutionary cycles have marked a breakthrough in our understanding of the accretion flow changes in the sub-Eddington regime in Galactic black hole binaries, their evidence in t…
Oort cloud Ecology. I. Extra-solar Oort clouds and the origin of asteroidal interlopers
Portegies Zwart, S.
We simulate the formation and evolution of Oort clouds around the 200 nearest stars (within ∼16 pc according to the Gaia DR2) database. This study is performed by numerically integrating the planets and minor bodies in orbit around the parent star and in the Galactic potential. The calculations start 1 Gyr ago and continue for 100 Myr into the fut…
The MURALES survey. IV. Searching for nuclear outflows in 3C radio galaxies at z < 0.3 with MUSE observations
Marconi, A.; Capetti, A.; Grandi, P. +13 more
We analyze VLT/MUSE observations of 37 radio galaxies from the Third Cambridge catalogue (3C) with redshift < 0.3 searching for nuclear outflows of ionized gas. These observations are part of the MURALES project (a MUse RAdio Loud Emission line Snapshot survey), whose main goal is to explore the feedback process in the most powerful radio-loud …