Search Publications

The Wolf-Rayet stars in the Large Magellanic Cloud. A comprehensive analysis of the WN class
DOI: 10.1051/0004-6361/201322696 Bibcode: 2014A&A...565A..27H

Foellmi, C.; Hamann, W. -R.; Oskinova, L. M. +6 more

Context. Massive stars, although being important building blocks of galaxies, are still not fully understood. This especially holds true for Wolf-Rayet (WR) stars with their strong mass loss, whose spectral analysis requires adequate model atmospheres.
Aims: Following our comprehensive studies of the WR stars in the Milky Way, we now present …

2014 Astronomy and Astrophysics
IUE eHST 188
The VLT-FLAMES Tarantula Survey. XVII. Physical and wind properties of massive stars at the top of the main sequence
DOI: 10.1051/0004-6361/201423643 Bibcode: 2014A&A...570A..38B

Crowther, P. A.; Herrero, A.; Simón-Díaz, S. +12 more

The evolution and fate of very massive stars (VMS) is tightly connected to their mass-loss properties. Their initial and final masses differ significantly as a result of mass loss. VMS have strong stellar winds and extremely high ionising fluxes, which are thought to be critical sources of both mechanical and radiative feedback in giant H ii regio…

2014 Astronomy and Astrophysics
IUE eHST 141
Dust in the diffuse interstellar medium. Extinction, emission, linear and circular polarisation
DOI: 10.1051/0004-6361/201321716 Bibcode: 2014A&A...561A..82S

Siebenmorgen, R.; Bagnulo, S.; Voshchinnikov, N. V.

We present a model for the diffuse interstellar dust that explains the observed wavelength-dependence of extinction, emission, and the linear and circular polarisation of light. The model is set up with a small number of parameters. It consists of a mixture of amorphous carbon and silicate grains with sizes from the molecular domain of 0.5 up to a…

2014 Astronomy and Astrophysics
IUE 99
Influence of physical galaxy properties on Lyα escape in star-forming galaxies
DOI: 10.1051/0004-6361/201321519 Bibcode: 2014A&A...561A..89A

Hayes, Matthew; Schaerer, Daniel; Östlin, Göran +4 more

Context. Among the different observational techniques used to select high-redshift galaxies, the hydrogen recombination line Lyman-alpha (Lyα) is of particular interest because it gives access to the measurement of cosmological quantities such as the star formation rate (SFR) of distant galaxy populations. However, interpreting this line and calib…

2014 Astronomy and Astrophysics
IUE 63
Constraining the structure of the transition disk HD 135344B (SAO 206462) by simultaneous modeling of multiwavelength gas and dust observations
DOI: 10.1051/0004-6361/201322534 Bibcode: 2014A&A...567A..51C

Pinte, C.; Ménard, F.; Duchêne, G. +14 more

Context. Constraining the gas and dust disk structure of transition disks, particularly in the inner dust cavity, is a crucial step toward understanding the link between them and planet formation. HD 135344B is an accreting (pre-)transition disk that displays the CO 4.7 µm emission extending tens of AU inside its 30 AU dust cavity.
Aims…

2014 Astronomy and Astrophysics
Herschel IUE eHST 53
Gas lines from the 5-Myr old optically thin disk around HD 141569A . Herschel observations and modeling
DOI: 10.1051/0004-6361/201322150 Bibcode: 2014A&A...561A..50T

Pinte, C.; Ménard, F.; Woitke, P. +20 more

Context. The gas- and dust dissipation processes in disks around young stars remain uncertain despite numerous studies. At the distance of ~99-116 pc, HD 141569A is one of the nearest HerbigAe stars that is surrounded by a tenuous disk, probably in transition between a massive primordial disk and a debris disk. Atomic and molecular gases have been…

2014 Astronomy and Astrophysics
AKARI Herschel ISO IUE 49
An edge-on translucent dust disk around the nearest AGB star, L2 Puppis. VLT/NACO spectro-imaging from 1.04 to 4.05 µm and VLTI interferometry
DOI: 10.1051/0004-6361/201323273 Bibcode: 2014A&A...564A..88K

Kervella, P.; Chiavassa, A.; Chesneau, O. +6 more

As the nearest known AGB star (d = 64 pc) and one of the brightest (mK ≈ -2), L2 Pup is a particularly interesting benchmark object to monitor the final stages of stellar evolution. We report new serendipitous imaging observations of this star with the VLT/NACO adaptive optics system in twelve narrow-band filters covering the…

2014 Astronomy and Astrophysics
Hipparcos IUE 47
The rapid evolution of the exciting star of the Stingray nebula
DOI: 10.1051/0004-6361/201323189 Bibcode: 2014A&A...565A..40R

Rauch, T.; Werner, K.; Kruk, J. W. +5 more

Context. SAO 244567, the exciting star of the Stingray nebula, is rapidly evolving. Previous analyses suggested that it has heated up from an effective temperature of about 21 kK in 1971 to over 50 kK in the 1990s. Canonical post-asymptotic giant branch evolution suggests a relatively high mass while previous analyses indicate a…

2014 Astronomy and Astrophysics
IUE eHST 34
The spectroscopic evolution of the recurrent nova T Pyxidis during its 2011 outburst. III. The ultraviolet development from iron curtain through the post-X-ray turnoff
DOI: 10.1051/0004-6361/201322545 Bibcode: 2014A&A...562A..28D

Sion, E. M.; Shore, S. N.; Mason, E. +3 more

We continue the analysis of the multiwavelength evolution of the recurrent nova T Pyx during its 2011 outburst, focussing on the spectral development on the 1150-3000 Å region. This extraordinary data set presents the longest temporal baseline high resolution view of the ultraviolet for any nova to date (classical or recurrent). The observations c…

2014 Astronomy and Astrophysics
IUE eHST 18
The virtual observatory service TheoSSA: Establishing a database of synthetic stellar flux standards . II. NLTE spectral analysis of the OB-type subdwarf Feige 110
DOI: 10.1051/0004-6361/201423711 Bibcode: 2014A&A...566A...3R

Rauch, T.; Werner, K.; Kruk, J. W. +3 more

Context. In the framework of the Virtual Observatory (VO), the German Astrophysical VO (GAVO) developed the registered service TheoSSA (Theoretical Stellar Spectra Access). It provides easy access to stellar spectral energy distributions (SEDs) and is intended to ingest SEDs calculated by any model-atmosphere code, generally for all effective temp…

2014 Astronomy and Astrophysics
IUE eHST 15