A Flash in the Dark: UVES Very Large Telescope High‐Resolution Spectroscopy of Gamma‐Ray Burst Afterglows

2005 ◽  
Vol 624 (2) ◽  
pp. 853-867 ◽  
Author(s):  
F. Fiore ◽  
V. D’Elia ◽  
D. Lazzati ◽  
R. Perna ◽  
L. Sbordone ◽  
...  
Keyword(s):  
High Resolution ◽  
Gamma Ray ◽  
High Resolution Spectroscopy ◽  
Large Telescope ◽  
Gamma Ray Burst ◽  
Very Large Telescope

scholarly journals Interstellar Matter with Very Large Telescopes

1984 ◽  
Vol 79 ◽  
pp. 675-678
Author(s):  
J. Lequeux
Keyword(s):  
High Resolution ◽  
Absorption Lines ◽  
High Resolution Spectroscopy ◽  
Interstellar Matter ◽  
Large Telescope ◽  
Interstellar Absorption ◽  
Near Ir ◽  
Very Large Telescope ◽  
Large Telescopes ◽  
Diffuse Matter

Interstellar matter is certainly one of the fields where a very large telescope (VLT) will prove to be most fruitful. This includes (somewhat paradoxically, but this will be explained later) the study of extended emissions. I will now examine in turn the different domains of interest for a VLT.I. Neutral diffuse matterOptical and near IR observations will mainly contribute to this domain through high-resolution spectroscopy of interstellar absorption lines in the spectra of stars. These lines are resonant lines of atoms (NaI, KI, etc.) or ions (CaII, TiII, etc.) as well as of some molecules (CH+, CH, CN, CS+, C2 in the near IR). Clearly this kind of study is always photon - limited; a VLT will collect more photons than present telescopes, thus increase the possibilities considerably.

High Resolution Spectroscopy of Gamma-Ray Burst Afterglows

2009 ◽  
Author(s):  
V. D’Elia ◽  
F. Fiore ◽  
F. Nicastro ◽  
R. Perna ◽  
Y. Krongold ◽  
...  
Keyword(s):  
High Resolution ◽  
Gamma Ray ◽  
High Resolution Spectroscopy ◽  
Gamma Ray Burst

scholarly journals Lithium abundance in lower red giant branch stars of Omega Centauri

2018 ◽  
Vol 618 ◽  
pp. A134 ◽  
Author(s):  
A. Mucciarelli ◽  
M. Salaris ◽  
L. Monaco ◽  
P. Bonifacio ◽  
X. Fu ◽  
...  
Keyword(s):  
High Resolution ◽  
Globular Clusters ◽  
Stellar System ◽  
The Other ◽  
Large Telescope ◽  
Lithium Abundance ◽  
Very Large Telescope ◽  
Red Giant ◽  
Giant Branch Stars ◽  
Branch Star

We present Li, Na, Al, and Fe abundances of 199 lower red giant branch star members of the stellar system Omega Centauri, using high-resolution spectra acquired with FLAMES at the Very Large Telescope. The A(Li) distribution is peaked at A(Li) ∼ 1 dex with a prominent tail towards lower values. The peak of the distribution well agrees with the lithium abundances measured in lower red giant branch stars in globular clusters and Galactic field stars. Stars with A(Li) ∼ 1 dex are found at metallicities lower than [Fe/H] ∼ –1.3 dex but they disappear at higher metallicities. On the other hand, Li-poor stars are found at all metallicities. The most metal-poor stars exhibit a clear Li–Na anti-correlation, where about 30% of the sample have A(Li) lower than ∼0.8 dex, while these stars represent a small fraction of normal globular clusters. Most of the stars with [Fe/H] > –1.6 dex are Li poor and Na rich. The Li depletion measured in these stars is not observed in globular clusters with similar metallicities and we demonstrate that it is not caused by the proposed helium enhancements and/or young ages. Hence, these stars formed from a gas already depleted in lithium. Finally, we note that Omega Centauri includes all the populations (Li-normal/Na-normal, Li-normal/Na-rich, and Li-poor/Na-rich stars) observed, to a lesser extent, in mono-metallic GCs.

High‐Resolution Spectroscopy of Gamma‐Ray Bursts with the Transient Gamma‐Ray Spectrometer

2000 ◽  
Vol 543 (1) ◽  
pp. 77-89 ◽  
Author(s):  
P. Kurczynski ◽  
D. Palmer ◽  
H. Seifert ◽  
B. J. Teegarden ◽  
N. Gehrels ◽  
...  
Keyword(s):  
High Resolution ◽  
Gamma Ray ◽  
Gamma Ray Bursts ◽  
High Resolution Spectroscopy ◽  
Gamma Ray Spectrometer

A high-resolution Ge spectrometer for Gamma-Ray burst astronomy

1995 ◽  
Vol 71 (1-4) ◽  
pp. 273-296 ◽  
Author(s):  
A. Owens ◽  
R. Baker ◽  
T. L. Cline ◽  
N. Gehrels ◽  
J. Jermakian ◽  
...  
Keyword(s):  
High Resolution ◽  
Gamma Ray ◽  
Gamma Ray Burst

scholarly journals Speckle Interferometry, Speckle Masking, Speckle Spectroscopy and Speckle Frame Selection

1984 ◽  
Vol 79 ◽  
pp. 337-345 ◽  
Author(s):  
Gerd Weigelt
Keyword(s):  
High Resolution ◽  
Speckle Interferometry ◽  
Large Telescope ◽  
Speckle Imaging ◽  
Frame Selection ◽  
Very Large Telescope

AbstractHigh-resolution speckle imaging is one of the most fascinating possibilities of a Very Large Telescope (VLT). Various speckle methods can yield a resolution of about 0.01" with a 8-m to 10-m VLT. As exiting as the resolution is the limiting magnitude of the speckle methods. The limiting magnitude is extremely seeingdependent. The following limiting magnitudes are possible with speckle interferometry, speckle masking and speckle spectroscopy:4" seeing: limiting magnitude 152" seeing: limiting magnitude 17.51" seeing: limiting magnitude 20 (!)

scholarly journals Comet 66P/du Toit: not a near-Earth main belt comet

2019 ◽  
Vol 631 ◽  
pp. A168
Author(s):  
Bin Yang ◽  
Emmanuël Jehin ◽  
Francisco J. Pozuelos ◽  
Youssef Moulane ◽  
Yoshiharu Shinnaka ◽  
...  
Keyword(s):  
High Resolution ◽  
Physical Properties ◽  
Orbital Evolution ◽  
Abundance Ratio ◽  
High Resolution Spectroscopy ◽  
Main Belt ◽  
Gaseous Species ◽  
Very Large Telescope ◽  
Short Period ◽  
Dynamical Simulations

Context. Main belt comets (MBCs) are a peculiar class of volatile-containing objects with comet-like morphology and asteroid-like orbits. However, MBCs are challenging targets to study remotely due to their small sizes and the relatively large distance they are from the Sun and the Earth. Recently, a number of weakly active short-period comets have been identified that might originate in the asteroid main belt. Among all of the known candidates, comet 66P/du Toit has been suggested to have one of the highest probabilities of coming from the main belt. Aims. The main goal of this study is to investigate the physical properties of 66P via spectroscopic and imaging observations to constrain its formation conditions. In particular, the isotopic abundance ratio and the ortho-to-para ratio (OPR) of gaseous species can be derived via high-resolution spectroscopy, which is sensitive to the formation temperature of the nucleus. Methods. We obtained medium and high-resolution spectra of 66P from 300–2500 nm with the X-shooter and the UVES instruments at the Very Large Telescope in July 2018. We also obtained a series of narrow-band images of 66P to monitor the gas and dust activity between May and July 2018 with TRAPPIST-South. In addition, we applied a dust model to characterize the dust coma of 66P and performed dynamical simulations to study the orbital evolution of 66P. Results. We derive the OPR of ammonia (NH3) in 66P to be 1.08 ± 0.06, which corresponds to a nuclear spin temperature of ~34 K. We compute the production rates of OH, NH, CN, C3, and C2 radicals and measure the dust proxy, Afρ. The dust analysis reveals that the coma can be best-fit with an anisotropic model and the peak dust production rate is about 55 kg s−1 at the perihelion distance of 1.29 au. Dynamical simulations show that 66P is moderately asteroidal with the capture time, tcap ~ 104 yr. Conclusions. Our observations demonstrate that the measured physical properties of 66P are consistent with typical short-period comets and differ significantly from other MBCs. Therefore, 66P is unlikely to have a main belt origin.

Gamma-ray burst observations by the HEAO-3 high-resolution gamma-ray spectrometer

1982 ◽  
Author(s):  
Wm. A. Wheaton ◽  
James C. Ling ◽  
William A. Mahoney ◽  
Guenter R. Riegler ◽  
Allan S. Jacobson
Keyword(s):  
High Resolution ◽  
Gamma Ray ◽  
Gamma Ray Burst ◽  
Gamma Ray Spectrometer ◽  
High Resolution Gamma
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