Search Publications
Non-LTE modelling of prominence fine structures using hydrogen Lyman-line profiles
Curdt, W.; Gunár, S.; Schwartz, P.
Aims: We perform a detailed statistical analysis of the spectral Lyman-line observations of the quiescent prominence observed on May 18, 2005.
Methods: We used a profile-to-profile comparison of the synthetic Lyman spectra obtained by 2D single-thread prominence fine-structure model as a starting point for a full statistical analysis of …
The naked nuclei of low ionization nuclear emission line regions
Capetti, Alessandro; Balmaverde, Barbara
We analyze HST spectra and Chandra observations of a sample of 21 low ionization nuclear emission line regions (LINERs), at least 18 of which genuine active galactic nuclei. We find a correlation between the X-rays and emission lines luminosities, extending over three orders of magnitude and with a dispersion of 0.36 dex; no differences emerge bet…
The Herschel view of the nebula around the luminous blue variable star AG Carinae
Nazé, Y.; Rauw, G.; Groenewegen, M. A. T. +5 more
Far-infrared Herschel PACS imaging and spectroscopic observations of the nebula around the luminous blue variable (LBV) star AG Car have been obtained along with optical imaging in the Hα+[ N ii ] filter. In the infrared light, the nebula appears as a clumpy ring shell that extends up to 1.2 pc with an inner radius of 0.4 pc. It coincides with the…
Micron-sized forsterite grains in the pre-planetary nebula of IRAS 17150-3224. Searching for clues to the mysterious evolution of massive AGB stars
Waters, L. B. F. M.; Blommaert, J. A. D. L.; Min, M. +3 more
Aims: We study the grain properties and location of the forsterite crystals in the circumstellar environment of the pre-planetary nebula (PPN) IRAS 17150-3224 in order to learn more about the as yet poorly understood evolutionary phase prior to the PPN.
Methods: We use the best-fit model for IRAS 17150-3224 of Meixner et al. (2002, ApJ, …
Far-infrared CO and H2O emission in intermediate-mass protostars
Karska, A.; Fuente, A.; Kristensen, L. E. +4 more
Context. Intermediate-mass young stellar objects (YSOs) provide a link to understanding how feedback from shocks and UV radiation scales from low- to high-mass star forming regions.
Aims: Our aim is to analyze excitation of CO and H2O in deeply embedded intermediate-mass YSOs and compare it with similar studies on low-mass and high…
Satellite content and quenching of star formation in galaxy groups at z ~ 1.8
Finoguenov, A.; Daddi, E.; Le Floc'h, E. +13 more
We study the properties of satellites in the environment of massive star-forming galaxies at z ~ 1.8 in the COSMOS field, using a sample of 215 galaxies on the main sequence of star formation with an average mass of ~1011M⊙. At z> 1.5, these galaxies typically trace halos of mass ≳1013M⊙. We use optic…
Trident: A three-pronged galaxy survey. I. Lyman alpha emitting galaxies at z ~ 2 in GOODS North
Östlin, G.; Hayes, M.; Guaita, L. +2 more
Context. Lyman alpha (Lyα) emitting galaxies (LAEs) are used to probe the distant universe and are therefore important for galaxy evolution studies and for providing clues to the nature of the epoch of reionization. However, the exact circumstances under which Lyα escapes a galaxy are still not fully understood.
Aims: The Trident project is d…
Super-diffusion versus competitive advection: a simulation
Gošić, M.; Giannattasio, F.; Berrilli, F. +3 more
Context. Magnetic element tracking is often used to study the transport and diffusion of the magnetic field on the solar photosphere. From the analysis of the displacement spectrum of these tracers, it has recently been agreed that a regime of super-diffusivity dominates the solar surface. Quite habitually this result is discussed in the framework…
Deriving physical parameters of unresolved star clusters. III. Application to M 31 PHAT clusters
Narbutis, D.; Vansevičius, V.; de Meulenaer, P. +1 more
Context. This study is the third of a series that investigates the degeneracy and stochasticity problems present in the determination of physical parameters such as age, mass, extinction, and metallicity of partially resolved or unresolved star cluster populations situated in external galaxies when using broad-band photometry.
Aims: This work…
The extended ROSAT-ESO Flux-Limited X-ray Galaxy Cluster Survey (REFLEX II). VI. Effect of massive neutrinos on the cosmological constraints from clusters
Böhringer, Hans; Chon, Gayoung
Clusters of galaxies are important probes for the large-scale structure that allow us to test cosmological models. With the REFLEX II galaxy cluster survey we previously derived tight constraints on the cosmological parameters for the matter density, Ωm, and the amplitude parameter of the matter density fluctuations, σ8. Wher…