Search Publications
High-resolution spectroscopic study of dwarf stars in the northern sky. Na to Zn abundances in two fields with radii of 20 degrees
Tautvaišienė, G.; Drazdauskas, A.; Mikolaitis, Š. +6 more
Context. New space missions, such as NASA TESS or ESA PLATO, will focus on bright stars, which have been largely ignored by modern large surveys, especially in the northern sky. Spectroscopic information is of paramount importance in characterising the stars and analysing planets possibly orbiting them, and in studying the Galactic disc evolution.…
From the stellar properties of HD 219134 to the internal compositions of its transiting exoplanets
Poretti, E.; Lebreton, Y.; Borsa, F. +8 more
Context. The harvest of exoplanet discoveries has opened the area of exoplanet characterisation. But this cannot be achieved without a careful analysis of the host star parameters.
Aims: The system of HD 219134 hosts two transiting exoplanets and at least two additional non-transiting exoplanets. We revisit the properties of this system using…
A broadband spectral analysis of 4U 1702-429 using XMM-Newton and BeppoSAX data
Santangelo, A.; Sanna, A.; Segreto, A. +8 more
Context. Most of the X-ray binary systems containing neutron stars classified as Atoll sources show two different spectral states, referred to as soft and hard. Moreover, a large number of these systems show a reflection component relativistically smeared in their spectra, which provides information on the innermost region of the system.
Aims…
Plasma injection into a solar coronal loop
Peter, H.; Li, L. P.
Context. The details of the spectral profiles of extreme UV emission lines from solar active regions contain key information for investigating the structure, dynamics, and energetics of the solar upper atmosphere.
Aims: We characterize the line profiles not only through the Doppler shift and intensity of the bulk part of the profile. More imp…
Solar wind charge exchange in cometary atmospheres. II. Analytical model
Alho, Markku; Simon Wedlund, Cyril; Nilsson, Hans +7 more
Context. Solar wind charge-changing reactions are of paramount importance to the physico-chemistry of the atmosphere of a comet because they mass-load the solar wind through an effective conversion of fast, light solar wind ions into slow, heavy cometary ions. The ESA/Rosetta mission to comet 67P/Churyumov-Gerasimenko (67P) provided a unique oppor…
Origin of hydrogen fluoride emission in the Orion Bar. An excellent tracer for CO-dark H2 gas clouds
Shipman, R. F.; van der Tak, F. F. S.; Tielens, A. G. G. M. +1 more
Context. The hydrogen fluoride (HF) molecule is seen in absorption in the interstellar medium (ISM) along many lines of sight. Surprisingly, it is observed in emission toward the Orion Bar, which is an interface between the ionized region around the Orion Trapezium stars and the Orion molecular cloud.
Aims: We aim to understand the origin of …
Identification of AGN in the XMM-Newton X-ray survey of the SMC
Maitra, Chandreyee; Haberl, Frank; Cioni, Maria-Rosa L. +2 more
Context. Finding active galactic nuclei (AGN) behind the Magellanic Clouds (MCs) is difficult because of the high stellar density in these fields. Although the first AGN behind the Small Magellanic Cloud (SMC) were reported in the 1980s, it is only recently that the number of AGN known behind the SMC has increased by several orders of magnitude. <…
ISPY - NaCo Imaging Survey for Planets around Young stars. Discovery of an M dwarf in the gap between HD 193571 and its debris ring
Reffert, Sabine; Metchev, Stanimir; Rickman, Emily L. +19 more
Context. The interaction between low-mass companions and the debris discs they reside in is still not fully understood. A debris disc can evolve due to self-stirring, a process in which planetesimals can excite their neighbours to the point of destructive collisions. In addition, the presence of a companion could further stir the disc (companion-s…
CLIcK: a Continuum and Line fItting Kit for circumstellar disks
Pascucci, Ilaria; Henning, Thomas; Liu, Yao
Infrared spectroscopy with medium to high spectral resolution is essential to characterize the gas content of circumstellar disks. Unfortunately, conducting continuum and line radiative transfer of thermochemical disk models is too time-consuming to carry out large parameter studies. Simpler approaches using a slab model to fit continuum-subtracte…
Heavy metal enrichment in the intermediate He-sdOB pulsator Feige 46
Heber, U.; Latour, M.; Dorsch, M.
The intermediate He-enriched hot subdwarf star Feige 46 was recently reported as the second member of the V366 Aqr (or He-sdOBV) pulsating class. Feige 46 is very similar to the prototype of the class, LS IV - 14°116, not only in terms of pulsational properties, but also in terms of atmospheric parameters and kinematic properties. LS IV - 14°116 i…