Search Publications
Evidence for stellar contamination in the transmission spectra of HAT-P-12b
Pallé, E.; Yan, F.; Chen, G. +4 more
Context. Transmission spectroscopy characterizes the wavelength dependence of transit depth, revealing atmospheric absorption features in planetary terminator regions. In this context, different optical transmission spectra of HAT-P-12b reported in previous studies exhibited discrepant atmospheric features (e.g., Rayleigh scattering and alkali abs…
A neural network-based methodology to select young stellar object candidates from IR surveys
Montillaud, J.; Cornu, D.
Context. Observed young stellar objects (YSOs) are used to study star formation and characterize star-forming regions. For this purpose, YSO candidate catalogs are compiled from various surveys, especially in the infrared (IR), and simple selection schemes in color-magnitude diagrams (CMDs) are often used to identify and classify YSOs.
Aims: …
Multi-instrument analysis of far-ultraviolet aurora in the southern hemisphere of comet 67P/Churyumov-Gerasimenko
Feldman, P. D.; Eriksson, A.; Biver, N. +9 more
Aims: We aim to determine whether dissociative excitation of cometary neutrals by electron impact is the major source of far-ultraviolet (FUV) emissions at comet 67P/Churyumov-Gerasimenko in the southern hemisphere at large heliocentric distances, both during quiet conditions and impacts of corotating interaction regions observed in the summe…
12C/13C ratio and CNO abundances in the classical very old metal-poor dwarf HD 140283
Spite, M.; Barbuy, B.; Spite, F.
Context. The isotope abundances provide powerful diagnostics of the chemical enrichment in our Galaxy. The star HD 140283 is one of the best-studied very metal-poor dwarf stars. It is very old, and the chemical abundance in this star is a good witness of the chemical composition of the matter in the early Galaxy.
Aims: The aim of this work is…
Multifrequency high spectral resolution observations of HCN toward the circumstellar envelope of Y Canum Venaticorum
Santander-García, M.; Cernicharo, J.; Greathouse, T. K. +7 more
High spectral resolution observations toward the low mass-loss rate C-rich, J-type asymptotic giant branch (AGB) star Y CVn were carried out at 7.5, 13.1, and 14.0 µm with the Echelon-cross-echelle Spectrograph mounted on the Stratospheric Observatory for Infrared Astronomy and the Texas Echelon-cross-echelle Spectrograph on the Infrared Tel…
ALMA observations of the early stages of substellar formation in the Lupus 1 and 3 molecular clouds
Hales, A.; de Gregorio-Monsalvo, I.; Bayo, A. +10 more
Context. The dominant mechanism leading to the formation of brown dwarfs (BDs) remains uncertain. While the census of Class II analogs in the substellar domain continues to grow, the most direct keys to formation, which are obtained from younger objects (pre-BD cores and proto-BDs), are limited by the very low number statistics available.
Aim…
Multi-wavelength VLTI study of the puffed-up inner rim of a circumbinary disc
Min, M.; Van Winckel, H.; Kamath, D. +3 more
Context. The presence of stable, compact circumbinary discs of gas and dust around post-asymptotic giant branch (post-AGB) binary systems has been well established. We focus on one such system, IRAS 08544−4431.
Aims: We present an interferometric multi-wavelength analysis of the circumstellar environment of IRAS 08544−4431. The aim is to cons…
On the size distribution of spots within sunspot groups
Solanki, Sami K.; Krivova, Natalie A.; Mandal, Sudip +1 more
The size distribution of sunspots provides key information about the generation and emergence processes of the solar magnetic field. Previous studies of size distribution have primarily focused on either the whole group or individual spot areas. In this paper we investigate the organisation of spot areas within sunspot groups. In particular, we an…
Small lobe of comet 67P: Characterization of the Wosret region with ROSETTA-OSIRIS
Sierks, H.; Barucci, M. A.; Fornasier, S. +3 more
Aims: We investigated Wosret, a region located on the small lobe of the 67P/Churyumov-Gerasimenko comet subject to strong heating during the perihelion passage. This region includes the two last landing sites of the Philae lander as well as, notably the final one, Abydos, where the lander performed most of its measurements. We study Wosret in…
G 112-43/44: A metal-poor binary star with a unique chemical composition and Helmi stream kinematics
Nissen, P. E.; Schuster, W. J.; Silva-Cabrera, J. S.
Context. Correlations between high-precision elemental abundance ratios and the kinematics of halo stars provide interesting information about the formation and early evolution of the Galaxy.
Aims: Element abundances of G 112-43/44, a metal-poor wide-orbit binary star with extreme kinematics, are revisited.
Methods: High-precision studie…