Search Publications
The evolutionary state of the red giant star L2 Puppis
Uttenthaler, S.
Context. L2 Puppis (L2 Pup) is a nearby red giant star and an important object in late-type star research because it has a dust disc and potentially a companion. Aims. L2 Pup is often called the second-closest asymptotic giant branch (AGB) star to the sun, second only to R Doradus. However, whether the star is inde…
A search for Galactic post-asymptotic giant branch stars in Gaia DR3
Dafonte, C.; González-Santamaría, I.; Manteiga, M. +3 more
Context. When low- and intermediate-mass stars leave the asymptotic giant branch (AGB) phase, and before they reach the planetary nebula stage, they enter a very brief and rather puzzling stellar evolutionary stage called post-AGB stage. The post-AGB phase lasts very briefly, about a few thousand years at most. The number of objects that are confi…
Chemical composition of planetary hosts: C, N, and α-element abundances
Tautvaišienė, G.; Mikolaitis, Š.; Minkevičiūtė, R. +4 more
Context. Accurate atmospheric parameters and chemical composition of planet hosts play a major role in characterising exoplanets and understanding their formation and evolution. Aims. Our objective is to uniformly determine atmospheric parameters and chemical abundances of carbon (C), nitrogen (N), oxygen(O), and the α-elements, magnesium (Mg) and…
Observation of solar energetic particles with Metis on board Solar Orbiter on February 25, 2023
Gissot, S.; Sasso, C.; Romoli, M. +29 more
Context. The Solar Orbiter Metis coronagraph captures images of the solar corona in both visible (VL) and ultraviolet (UV) light. Tracks ascribable to the passage of galactic and solar particles appear in the Metis images. An algorithm implemented in the Metis processing electronics allows us to separate the pixels fired by VL photons from those c…
Determination of metallicities of red giant stars using machine learning techniques applied to the narrow and broadband photometry of the S-PLUS survey
Almeida-Fernandes, F.; Schoenell, W.; Daflon, S. +8 more
Aims. The aim of this study is to obtain metallicities of red giant stars from the Southern Photometric Local Universe Survey (S-PLUS) and to classify giant and dwarf stars using artificial neural networks applied to the S-PLUS photometry. Methods. We combined the five broadband and seven narrow-band filters of S-PLUS – especially centred on promi…
3C 273 host galaxy with Hubble Space Telescope coronagraphy
Debes, John H.; Perrin, Marshall D.; Ren, Bin B. +6 more
The close-in regions of bright quasars' host galaxies have been difficult to image due to the overwhelming light coming from quasars. With coronagraphic observations in visible light using the Space Telescope Imaging Spectrograph (STIS) on the Hubble Space Telescope, we removed 3C 273 quasar light using color-matching reference stars. The observat…
A new atmospheric characterization of the sub-stellar companion HR 2562 B with JWST/MIRI observations
Tremblin, P.; Stolker, T.; Lagage, P. O. +8 more
Context. HR 2562 B is a planetary-mass companion at an angular separation of 0.56″ (19 au) from the host star, which is also a member of a select number of L/T transitional objects orbiting a young star. This companion gives us a great opportunity to contextualize and understand the evolution of young objects in the L/T transition. However, the ma…
A study of centaur (54598) Bienor from multiple stellar occultations and rotational light curves
Colas, F.; Souami, D.; Redfield, S. +40 more
Context. Centaurs, distinguished by their volatile-rich compositions, play a pivotal role in understanding the formation and evolution of the early Solar System, as they represent remnants of the primordial material that populated the outer regions. Stellar occultations offer a means to investigate their physical properties, including shape and ro…
KMT-2023-BLG-0416, KMT-2023-BLG-1454, KMT-2023-BLG-1642: Microlensing planets identified from partially covered signals
Han, Cheongho; Udalski, Andrzej; Lee, Chung-Uk +32 more
Aims: We investigate the 2023 season data from high-cadence microlensing surveys with the aim of detecting partially covered shortterm signals and revealing their underlying astrophysical origins. Through this analysis, we ascertain that the signals observed in the lensing events KMT-2023-BLG-0416, KMT-2023-BLG-1454, and KMT-2023-BLG-1642 are…
eROSITA (eRASS1) study of the Canis Major overdensity: Developing a multi-wavelength algorithm for classifying faint X-ray sources
Sasaki, Manami; Saeedi, Sara; Robrade, Jan +6 more
Context. Using data from eROSITA (extended Roentgen Survey with an Imaging Telescope Array) on board Spektrum-Roentgen- Gamma (Spektr-RG, SRG) taken during the first eROSITAall-sky survey (eRASS1), we performed the first X-ray classification and population study in the field of the Canis Major overdensity (CMa OD), which is an elliptical-shaped st…