scholarly journals Du flou des images astronomiques à un prix Nobel de physique

2021 ◽  
pp. 21-27
Author(s):  
Pierre Léna ◽  
Guy Perrin
Keyword(s):  
Large Telescope ◽  
Very Large Telescope

Deux des lauréats du prix Nobel de physique 2020 sont primés pour leurs observations 1, qui ont confirmé l’existence d’un trou noir supermassif au centre de notre Galaxie. En améliorant considérablement, jusqu’à un facteur de plus de cent-mille parfois, la résolution spatiale des télescopes utilisés, ils ont exploré un véritable laboratoire de relativité générale, au plus près de cette singularité de l’espace-temps. Ces gains en résolution résultent d’un franchissement de la limitation imposée par l’atmosphère terrestre, grâce à l’interférométrie des tavelures (1970), puis l’optique adaptative (1989), enfin la mise en service de télescopes optiques géants (ca. 2000), et du réseau interférométrique du Very Large Telescope européen.

scholarly journals Unidentified emission features in the R Coronae Borealis star V854 Centauri

2018 ◽  
Vol 610 ◽  
pp. L6 ◽  
Author(s):  
L. C. Oostrum ◽  
B. B. Ochsendorf ◽  
L. Kaper ◽  
A. G. G. M. Tielens
Keyword(s):  
Near Infrared ◽  
Physical Nature ◽  
The Other ◽  
Large Telescope ◽  
Circumstellar Material ◽  
Spatially Resolved ◽  
Broad Emission ◽  
Very Large Telescope ◽  
New Feature ◽  
Molecular Nature

During its 2012 decline, the R Coronae Borealis star (RCB) V854 Cen was spectroscopically monitored with X-shooter on the ESO Very Large Telescope. The obscured optical and near-infrared spectrum exhibits many narrow and several broad emission features, as previously observed. The envelope is spatially resolved along the slit and allows for a detailed study of the circumstellar material. In this Letter, we report on the properties of a number of unidentified visual emission features (UFs), including the detection of a new feature at 8692 Å. These UFs have been observed in the Red Rectangle (RR), but their chemical and physical nature is still a mystery. The previously known UFs behave similarly in the RR and in V854 Cen, but are not detected in six other observed RCBs. Some hydrogen might be required for the formation of their carrier(s). The λ8692 UF is present in all RCBs. Its carrier is likely of a carbonaceous molecular nature, presumably different from that of the other UFs.

The Four‐Quadrant Phase Mask Coronagraph. IV. First Light at the Very Large Telescope

2004 ◽  
Vol 116 (825) ◽  
pp. 1061-1071 ◽  
Author(s):  
A. Boccaletti ◽  
P. Riaud ◽  
P. Baudoz ◽  
J. Baudrand ◽  
D. Rouan ◽  
...  
Keyword(s):  
Phase Mask ◽  
Large Telescope ◽  
Very Large Telescope ◽  
Four Quadrant

scholarly journals Very Large Telescope observations of Gomez’s Hamburger: Insights into a young protoplanet candidate

2015 ◽  
Vol 578 ◽  
pp. L8 ◽  
Author(s):  
O. Berné ◽  
A. Fuente ◽  
E. Pantin ◽  
V. Bujarrabal ◽  
C. Baruteau ◽  
...  
Keyword(s):  
Large Telescope ◽  
Very Large Telescope

scholarly journals Clumps and Rings of Ejecta in SNR 0540–69.3 as Seen in 3D

2021 ◽  
Vol 922 (2) ◽  
pp. 265
Author(s):  
J. Larsson ◽  
J. Sollerman ◽  
J. D. Lyman ◽  
J. Spyromilio ◽  
L. Tenhu ◽  
...  
Keyword(s):  
3D Reconstruction ◽  
Supernova Remnants ◽  
Alternative Explanation ◽  
Type Ii ◽  
Large Telescope ◽  
Very Large Telescope ◽  
Balmer Lines ◽  
Pulsar Wind

Abstract The distribution of ejecta in young supernova remnants offers a powerful observational probe of their explosions and progenitors. Here we present a 3D reconstruction of the ejecta in SNR 0540-69.3, which is an O-rich remnant with a pulsar wind nebula located in the LMC. We use observations from the Very Large Telescope (VLT)/MUSE to study Hβ, [O iii] λ λ4959, 5007, Hα, [S ii] λ λ6717, 6731, [Ar iii] λ7136, and [S iii] λ9069. This is complemented by 2D spectra from VLT/X-shooter, which also cover [O ii] λ λ3726, 3729, and [Fe ii] λ12567. We identify three main emission components: (i) clumpy rings in the inner nebula (≲1000 km s−1) with similar morphologies in all lines; (ii) faint extended [O iii] emission dominated by an irregular ring-like structure with radius ∼1600 km s−1 and inclination ∼40°, but with maximal velocities reaching ∼3000 km s−1; and (iii) a blob of Hα and Hβ located southeast of the pulsar at velocities ∼1500–3500 km s−1. We analyze the geometry using a clump-finding algorithm and use the clumps in the [O iii] ring to estimate an age of 1146 ± 116 yr. The observations favor an interpretation of the [O iii] ring as ejecta, while the origin of the H-blob is more uncertain. An alternative explanation is that it is the blown-off envelope of a binary companion. From the detection of Balmer lines in the innermost ejecta we confirm that SNR 0540 was a Type II supernova and that hydrogen was mixed down to low velocities in the explosion.

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