Search Publications
Generalised model-independent characterisation of strong gravitational lenses. II. Transformation matrix between multiple images
Wagner, J.; Tessore, N.
We determine the transformation matrix that maps multiple images with identifiable resolved features onto one another and that is based on a Taylor-expanded lensing potential in the vicinity of a point on the critical curve within our model-independent lens characterisation approach. From the transformation matrix, the same information about the p…
The Caviar software package for the astrometric reduction of Cassini ISS images: description and examples
Baillie, K.; Cooper, N. J.; Lainey, V. +6 more
Aims: Caviar is a software package designed for the astrometric measurement of natural satellite positions in images taken using the Imaging Science Subsystem (ISS) of the Cassini spacecraft. Aspects of the structure, functionality, and use of the software are described, and examples are provided. The integrity of the software is demonstrated…
Asteroseismic potential of CHEOPS
Moya, A.; Bonfanti, A.; Barrado, D. +3 more
Context. Asteroseismology has been impressively boosted during the last decade mainly thanks to space missions such as Kepler/K2 and CoRoT. This has a large impact, in particular, in exoplanetary sciences since the accurate characterization of the exoplanets is convoluted in most cases with the characterization of their hosting star. In the decade…
Statistical analysis of UV spectra of a quiescent prominence observed by IRIS
Heinzel, P.; Jejčič, S.; Gunár, S. +2 more
Context. The paper analyzes the structure and dynamics of a quiescent prominence that occurred on October 22, 2013 and was observed by several instruments including the Interface Region Imaging Spectrograph (IRIS).
Aims: We aim to determine the physical characteristics of the observed prominence using Mg II k and h (2796 and 2803 Å), C II (13…
Testing a double AGN hypothesis for Mrk 273
Sanders, D. B.; Iwasawa, K.; Evans, A. S. +3 more
The ultra-luminous infrared galaxy (ULIRG) Mrk 273 contains two infrared nuclei, N and SW, separated by 1 arcsecond. A Chandra observation has identified the SW nucleus as an absorbed X-ray source with NH 4 × 1023 cm-2 but also hinted at the possible presence of a Compton-thick AGN in the N nucleus, where a black h…
AKARI mid-infrared slitless spectroscopic survey of star-forming galaxies at z ≲ 0.5
Im, M.; White, G. J.; Inami, H. +24 more
Context. Deep mid-infrared (MIR) surveys have revealed numerous strongly star-forming galaxies at redshift z ≲ 2. Their MIR fluxes are produced by a combination of continuum and polycyclic aromatic hydrocarbon (PAH) emission features. The PAH features can dominate the total MIR flux, but are difficult to measure without spectroscopy.
Aims: We…
LQAC-4: Fourth release of the Large Quasar Astrometric Catalogue. Compilation of 443 725 objects including cross-identifications with Gaia DR1
Barache, C.; Souchay, J.; Taris, F. +3 more
Context. From an astrometric point of view, quasars constitute the best and almost ideal reference objects in the celestial sphere, with a priori no significant proper motion. Since the third release of the Large Quasar Astrometric Catalogue (LQAC-3), a large number of quasars have been discovered, in particular those coming from the DR12Q release…
Chemical abundance analysis of red giant branch stars in the globular cluster E3
Monaco, L.; Mucciarelli, A.; Villanova, S. +2 more
Context. Globular clusters are known to host multiple stellar populations, which are a signature of their formation process. The globular cluster E3 is one of the few low-mass globulars that is thought not to host multiple populations.
Aims: We investigate red giant branch stars in E3 with the aim of providing a first detailed chemical invent…
Energy conversion in cometary atmospheres. Hybrid modeling of 67P/Churyumov-Gerasimenko
Kallio, E.; Gunell, H.; Nilsson, H. +6 more
Aims: We wish to investigate the energy conversion between particles and electromagnetic fields and determine the location where it occurs in the plasma environment of comets.
Methods: We used a hybrid plasma model that included photoionization, and we considered two cases of the solar extreme ultraviolet flux. Other parameters correspon…
Yet another UFO in the X-ray spectrum of a high-z lensed QSO
Cappi, M.; Ponti, G.; Vignali, C. +6 more
Aim. Ultra-fast outflows (UFO) appear to be common in local active galactic nuclei (AGN) and may be powerful enough (Ėkin ≥ 1% of Lbol) to effectively quench the star formation in their host galaxies. To test feedback models based on AGN outflows, it is mandatory to investigate UFOs near the peak of AGN activity, that is, at …