Search Publications
Orbital and physical parameters of eclipsing binaries from the All-Sky Automated Survey catalogue. X. Three high-contrast systems with secondaries detected with IR spectroscopy
Tamura, M.; Kambe, E.; Niemczura, E. +14 more
Aims: We present results of the combined photometric and spectroscopic analysis of three detached eclipsing binaries, the secondary components of which are not visible or are very hard to identify in the optical spectra - ASAS J052743-0359.7, ASAS J065134-2211.5, and ASAS J073507-0905.7. The first one is the known visual binary ADS 4022, and …
Photometry of K2 Campaign 9 bulge data
Udalski, A.; Poleski, R.; Gould, A. +4 more
In its Campaign 9, K2 observed dense regions toward the Galactic bulge in order to constrain the microlensing parallaxes and probe for free-floating planets. Photometric reduction of the K2 bulge data poses a significant challenge due to a combination of the very high stellar density, large pixels of the Kepler camera, and the pointing drift of th…
A VLT/FLAMES survey for massive binaries in Westerlund 1. V. The X-ray selected blue stragglers Wd1-27 and -30a
Negueruela, I.; Najarro, F.; Clark, J. S. +3 more
Context. Recent observational studies indicate that a large number of OB stars are found within binary systems which may be expected to interact during their lifetimes. Significant mass transfer or indeed merger of both components is expected to modify evolutionary pathways, facilitating the production of exceptionally massive stars which will pre…
Full inversion of solar relativistic electron events measured by the Helios spacecraft
Lario, D.; Heber, B.; Aran, A. +2 more
Context. The Parker Solar Probe and the incoming Solar Orbiter mission will provide measurements of solar energetic particle (SEP) events at close heliocentric distances from the Sun. Up to present, the largest data set of SEP events in the inner heliosphere are the observations by the two Helios spacecraft.
Aims: We re-visit a sample of 15 s…
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 …