Search Publications
Modelling the evolution of the Galactic disc scale height traced by open clusters
Moitinho, André; Moreira, Sandro; Silva, André +1 more
Context. The scale height (SH) of the spatial distribution of open clusters (OCs) in the Milky Way exhibits a well-known increase with age that is usually interpreted as evidence for dynamical heating of the disc or for the disc having been thicker in the past. Aims. We address the increase in the SH with age of the OC population from a different …
High-resolution observational analysis of flare ribbon fine structures
Fletcher, Lyndsay; Nóbrega-Siverio, Daniel; Aulanier, Guillaume +4 more
Context. Since the mechanism of energy release from solar flares is still not fully understood, the study of fine-scale features developing during flares becomes important for progressing towards a consistent picture of the essential physical mechanisms. Aims. Solar flares release most of their luminous energy in the chromosphere. These luminous s…
Chemical Evolution of R-process Elements in Stars (CERES): III. Chemical abundances of neutron capture elements from Ba to Eu
Hansen, C. J.; Bonifacio, P.; Caffau, E. +11 more
Context. The chemical abundances of elements such as barium and the lanthanides are essential to understand the nucleosynthesis of heavy elements in the early Universe as well as the contribution of different neutron capture processes (for example slow versus rapid) at different epochs. Aims. The Chemical Evolution of R-process Elements in Stars (…
Accelerating lensed quasar discovery and modeling with physics-informed variational autoencoders
Grillo, Claudio; Suyu, Sherry H.; Andika, Irham T. +5 more
Strongly lensed quasars provide valuable insights into the rate of cosmic expansion, the distribution of dark matter in foreground deflectors, and the characteristics of quasar hosts. However, detecting them in astronomical images is difficult due to the prevalence of non-lensing objects. To address this challenge, we developed a generative deep l…
Recent star formation episodes in the Galaxy: Impact on its chemical properties and the evolution of its abundance gradient
Prantzos, Nikos; Chen, Tianxiang
Aims. We investigate the chemical evolution of the Milky Way disc exploring various schemes of recent (past several Gyr) star formation episodes, as reported in recent observational works. Methods. We used a semi-analytical model with parametrized radial migration, and we introduced Gaussian star formation episodes constrained by the recent observ…
Radial evolution of interplanetary coronal mass ejection-associated particle acceleration observed by Solar Orbiter and ACE
Li, Gang; Kouloumvakos, Athanasios; Wimmer-Schweingruber, Robert F. +5 more
On 2022 March 10 a coronal mass ejection erupted from the Sun, resulting in Solar Orbiter observations at 0.45 au of both dispersive solar energetic particles arriving prior to the interplanetary coronal mass ejection (ICME) and locally accelerated particles near the ICME-associated shock structure as it passed the spacecraft on 2022 March 11. Thi…
Cosmic rays cannot explain the high ionisation rates in the Galactic centre
Gabici, S.; Recchia, S.; Ravikularaman, S. +1 more
Context. The H2 ionisation rate in the central molecular zone, located in the Galactic centre, is estimated to be ζ ∼ 2 × 10‑14 s‑1, based on observations of H3+ lines. This value is two to three orders of magnitude larger than that measured anywhere else in the Galaxy. Aims. Due to the high d…
The COBREX archival survey: Improved constraints on the occurrence rate of wide-orbit substellar companions: I. A uniform re-analysis of 400 stars from the GPIES survey
Meunier, N.; Kiefer, F.; Lagrange, A. -M. +7 more
Context. Direct imaging (DI) campaigns are uniquely suited to probing the outer regions around young stars in pursuit of giant exoplanet and brown dwarf companions, providing key complementary information to radial velocity (RV) and transit searches for demographic studies. However, the critical 5–20 au region, where most giant planets are thought…
Solar energetic particles injected inside and outside a magnetic cloud: The widespread solar energetic particle event on 2022 January 20
Palmerio, E.; Jebaraj, I. C.; Laitinen, T. +22 more
Context. On 2022 January 20, the Energetic Particle Detector (EPD) on board Solar Orbiter measured a solar energetic particle (SEP) event showing unusual first arriving particles from the anti-Sun direction. Near-Earth spacecraft separated by 17° in longitude to the west of Solar Orbiter measured classic anti-sunward-directed fluxes. STEREO-A and …
VLT VIMOS integral field spectroscopy of the nova remnant FH Ser
Guerrero, M. A.; Toalá, J. A.; Santamaría, E. +4 more
Context. The source FH Ser experienced a slow classical nova outburst in February 1970 that was the first ever observed at UV, optical, and IR wavelengths. Its nova remnant is elliptical and has multiple knots. A peculiar ring-like filament lies along its minor axis. Aims. We investigate here the true 3D spatio-kinematical structure of FH Ser to a…