Search Publications
The origin of the escape of Lyman α and ionizing photons in Lyman continuum emitters
Chisholm, J.; Schaerer, D.; Verhamme, A. +2 more
Context. Identifying the physical mechanisms driving the escape of Lyman continuum (LyC) photons is crucial for the search of Lyman continuum emitter (LCE) candidates.
Aims: To understand the physical properties involved in the leakage of LyC photons, we investigate the connection between the H I covering fraction, H I velocity width, the Lym…
Dynamical traceback age of the β Pictoris moving group
Miret-Roig, N.; Bouy, H.; Figueras, F. +7 more
Context. The β Pictoris moving group is one of the most well-known young associations in the solar neighbourhood and several members are known to host circumstellar discs, planets, and comets. Measuring its age precisely is essential to the study of several astrophysical processes, such as planet formation and disc evolution, which are strongly ag…
Is HR 6819 a triple system containing a black hole?. An alternative explanation
Shenar, T.; Sana, H.; Hawcroft, C. +10 more
Context. HR 6819 was recently proposed to be a triple system consisting of an inner B-type giant plus black hole (BH) binary with an orbital period of 40 d and an outer Be tertiary. This interpretation is mainly based on two inferences: that the emission attributed to the outer Be star is stationary and that the inner star, which is used as mass c…
Variability of OB stars from TESS southern Sectors 1-13 and high-resolution IACOB and OWN spectroscopy
Simón-Díaz, S.; Aerts, C.; Castro, N. +6 more
Context. The lack of high-precision long-term continuous photometric data for large samples of stars has impeded the large-scale exploration of pulsational variability in the OB star regime. As a result, the candidates for in-depth asteroseismic modelling have remained limited to a few dozen dwarfs. The TESS nominal space mission has surveyed the …
Cosmic dissonance: are new physics or systematics behind a short sound horizon?
Treu, Tommaso; Fassnacht, Christopher D.; Birrer, Simon +12 more
Context. Persistent tension between low-redshift observations and the cosmic microwave background radiation (CMB), in terms of two fundamental distance scales set by the sound horizon rd and the Hubble constant H0, suggests new physics beyond the Standard Model, departures from concordance cosmology, or residual systematics. …
Hot Exoplanet Atmospheres Resolved with Transit Spectroscopy (HEARTS). III. Atmospheric structure of the misaligned ultra-hot Jupiter WASP-121b
Heng, K.; Ehrenreich, D.; Lendl, M. +21 more
Ultra-hot Jupiters offer interesting prospects for expanding our theories on dynamical evolution and the properties of extremely irradiated atmospheres. In this context, we present the analysis of new optical spectroscopy for the transiting ultra-hot Jupiter WASP-121b. We first refine the orbital properties of WASP-121b, which is on a nearly polar…
The Solar Orbiter Science Activity Plan. Translating solar and heliospheric physics questions into action
Lewis, G. R.; Fedorov, A.; Livi, S. +182 more
Solar Orbiter is the first space mission observing the solar plasma both in situ and remotely, from a close distance, in and out of the ecliptic. The ultimate goal is to understand how the Sun produces and controls the heliosphere, filling the Solar System and driving the planetary environments. With six remote-sensing and four in-situ instrument …
Direct confirmation of the radial-velocity planet β Pictoris c
Genzel, R.; Sturm, E.; Tacconi, L. J. +92 more
Context. Methods used to detect giant exoplanets can be broadly divided into two categories: indirect and direct. Indirect methods are more sensitive to planets with a small orbital period, whereas direct detection is more sensitive to planets orbiting at a large distance from their host star. This dichotomy makes it difficult to combine the two t…
The hot dayside and asymmetric transit of WASP-189 b seen by CHEOPS
Guterman, P.; Alonso, R.; Deleuil, M. +103 more
The CHEOPS space mission dedicated to exoplanet follow-up was launched in December 2019, equipped with the capacity to perform photometric measurements at the 20 ppm level. As CHEOPS carries out its observations in a broad optical passband, it can provide insights into the reflected light from exoplanets and constrain the short-wavelength thermal …
A He I upper atmosphere around the warm Neptune GJ 3470 b
Alonso-Floriano, F. J.; Sánchez-López, A.; López-Puertas, M. +24 more
High resolution transit spectroscopy has proven to be a reliable technique for the characterization of the chemical composition of exoplanet atmospheres. Taking advantage of the broad spectral coverage of the CARMENES spectrograph, we initiated a survey aimed at characterizing a broad range of planetary systems. Here, we report our observations of…