Search Publications
Three-Dimensional Optimal Spectral Extraction (TDOSE) from integral field spectroscopy
Inami, H.; Schmidt, K. B.; Krajnović, D. +8 more
The amount of integral field spectrograph (IFS) data has grown considerably over the last few decades. The demand for tools to analyze such data is therefore bigger now than ever. We present a flexible Python tool for Three-Dimensional Optimal Spectral Extraction (TDOSE) from IFS data cubes. TDOSE works on any three-dimensional data cube and bases…
Precise radial velocities of giant stars. XIII. A second Jupiter orbiting in 4:3 resonance in the 7 CMa system
Quirrenbach, A.; Grundahl, F.; Albrecht, S. +8 more
We report the discovery of a second planet orbiting the K giant star 7 CMa based on 166 high-precision radial velocities obtained with Lick, HARPS, UCLES, and SONG. The periodogram analysis reveals two periodic signals of approximately 745 and 980 d, associated with planetary companions. A double-Keplerian orbital fit of the data reveals two Jupit…
The Hubble Catalog of Variables (HCV)
Hatzidimitriou, D.; Rest, A.; Georgantopoulos, I. +33 more
Aims: Over its lifetime and despite not being a survey telescope, the Hubble Space Telescope (HST) has obtained multi-epoch observations by multiple, diverse observing programs, providing the opportunity for a comprehensive variability search aiming to uncover new variables. We have therefore undertaken the task of creating a catalog of varia…
Pronounced morphological changes in a southern active zone on comet 67P/Churyumov-Gerasimenko
Lamy, P. L.; Lara, L. M.; Bertaux, J. -L. +30 more
A smooth deposit in the southern Khonsu region has been seen in ESA/Rosetta observations as active during the second half of 2015, when the southern summer coincided with the perihelion passage of 67P/Churyumov-Gerasimenko (67P). Image color sequences acquired by the OSIRIS instrument in the period of January 2015 to July 2016, pre- and post-perih…
Confronting expansion distances of planetary nebulae with Gaia DR2 measurements
Steffen, M.; Schönberner, D.
Context. Individual distances to planetary nebulae are of the utmost relevance for our understanding of post-asymptotic giant-branch evolution because they allow a precise determination of stellar and nebular properties. Also, objects with individual distances serve as calibrators for the so-called statistical distances based on secondary nebular …
Distribution of red clump stars does not support the X-shaped Galactic bulge
López-Corredoira, M.; Lee, Y. -W.; Garzón, F. +1 more
Context. Claims of an X-shaped Galactic bulge were based on the assumption of red clump stars as standard candles in some lines of sight crossing the off-plane bulge. However, some doubts have been cast on whether the two peaks in star counts along the line of sight really represent a double peak in the density distribution, or whether there is so…
Hierarchical Bayesian model to infer PL(Z) relations using Gaia parallaxes
Sarro, L. M.; Clementini, G.; Garofalo, A. +2 more
In a recent study we analysed period-luminosity-metallicity (PLZ) relations for RR Lyrae stars using the Gaia Data Release 2 (DR2) parallaxes. It built on a previous work that was based on the first Gaia Data Release (DR1), and also included period-luminosity (PL) relations for Cepheids and RR Lyrae stars. The method used to infer the relations fr…
Analysis of night-side dust activity on comet 67P observed by VIRTIS-M: a new method to constrain the thermal inertia on the surface
Mottola, S.; Naletto, G.; Vincent, J. -B. +26 more
On 2015 July 18, near perihelion at a heliocentric distance of 1.28 au, the Visible InfraRed Thermal Imaging Spectrometer (VIRTIS-M) on board the Rosetta spacecraft had the opportunity of observing dust activity in the inner coma with a view of the night side (shadowed side) of comet 67P/Churyumov-Gerasimenko. At the time of the measurements we pr…
The XMM-Newton wide field survey in the COSMOS field: Clustering dependence of X-ray selected AGN on host galaxy properties
Finoguenov, A.; Salvato, M.; Gilli, R. +5 more
Aims: We study the spatial clustering of 632 (1130) XMM-COSMOS active galactic nuclei (AGNs) with known spectroscopic or photometric redshifts in the range z = [0.1-2.5] in order to measure the AGN bias and estimate the typical mass of the hosting dark matter (DM) halo as a function of AGN host galaxy properties.
Methods: We created AGN …
3D thermal modeling of two selected regions on comet 67P and comparison with Rosetta/MIRO measurements
Skorov, Yuri; Macher, Wolfgang; Rezac, Ladislav +3 more
Context. The Microwave Instrument for the Rosetta Orbiter (MIRO) was one of the key instruments of the Rosetta mission, which acquired a wealth of data, in particular as the orbiter moved in the close environment of comet 67P/Churyumov-Gerasimenko (August 2014-September 2016). It was the only instrument of the Rosetta payload that was able to meas…