Search Publications
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…
Stellar cusp and warm dust at the heart of NGC 1068
Rouan, D.; Gratadour, D.; Grosset, L.
Aims: Establishing precisely how stars and interstellar medium distribute within the central 100 pc area around an AGN, down to the pc scale, is key to understanding the late stages of transfer of matter onto the accretion disc.
Methods: Using adaptive optics-assisted (SPHERE-VLT) near-IR images in the H band, Ks band, and sev…
A particular carbon-chain-producing region: L1489 starless core
Kim, Kee-Tae; Liu, Tie; Yuan, Jinghua +14 more
We detected carbon-chain molecules (CCMs) HC2n+1N (n = 1-3) and C3S in Ku band as well as high-energy excitation lines including C4H N = 9-8, J = 17/2-15/2, 19/2-17/2, and CH3CCH J = 5-4, K = 2 in the 3 mm band toward a starless core called the eastern molecular core (EMC) of L1489 IRS. Maps o…
BRITE photometry of the massive post-RLOF system HD149 404
Gosset, E.; Handler, G.; Wade, G. A. +12 more
Context. HD 149 404 is an evolved non-eclipsing O-star binary that has previously undergone a Roche lobe overflow interaction.
Aims: Understanding some key properties of the system requires a determination of the orbital inclination and of the dimensions of the components.
Methods: The BRITE-Heweliusz satellite was used to collect photom…
Leaves on trees: identifying halo stars with extreme gradient boosted trees
Helmi, Amina; Veljanoski, Jovan; Breddels, Maarten +1 more
Context. Extended stellar haloes are a natural by-product of the hierarchical formation of massive galaxies like the Milky Way. If merging is a non-negligible factor in the growth of our Galaxy, evidence of such events should be encoded in its stellar halo. The reliable identification of genuine halo stars is a challenging task, however.
Aims…