Echelle Spectroscopy of Interstellar Absorption toward μ Columbae with the Goddard High Resolution Spectrograph

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.

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Echelle Spectroscopy of a Metal-Rich K Giant in Baade's Window Using the Keck High-Resolution Spectrograph

The Astronomical Journal ◽

10.1086/117978 ◽

1996 ◽

Vol 111 ◽

pp. 2439 ◽

Cited By ~ 18

Author(s):

Sandra Castro ◽

R. Michael Rich ◽

Andrew McWilliam ◽

Luis C. Ho ◽

Hyron Spinrad ◽

...

Keyword(s):

High Resolution ◽

Echelle Spectroscopy

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The Properties of Near-Infrared Diffuse Interstellar Bands

Proceedings of the International Astronomical Union ◽

10.1017/s1743921313015652 ◽

2013 ◽

Vol 9 (S297) ◽

pp. 100-102

Author(s):

M. G. Rawlings ◽

A. J. Adamson ◽

B. J. McCall ◽

T. H. Kerr

Keyword(s):

High Resolution ◽

Near Infrared ◽

Diffuse Interstellar Bands ◽

Echelle Spectroscopy

AbstractIn addition to the hundreds of known visual-wavelength Diffuse Interstellar Bands (DIBs), a number of DIBs in the near-infrared (NIR) are now also known to exist. We present here high-resolution UKIRT echelle spectroscopy of two of the NIR DIBs toward sightlines exhibiting a range of visual extinctions. Variations in the strengths and profile shapes of the bands are considered in the context of known properties of the narrow DIBs at visual wavelengths.

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Atomic and Molecular Interstellar Absorption Lines toward the High Galactic Latitude Stars HD 141569 and HD 157841 at Ultra–High Resolution

The Astrophysical Journal ◽

10.1086/306042 ◽

1998 ◽

Vol 504 (1) ◽

pp. 522-532 ◽

Cited By ~ 14

Author(s):

M. S. Sahu ◽

J. C. Blades ◽

L. He ◽

Dap Hartmann ◽

M. J. Barlow ◽

...

Keyword(s):

High Resolution ◽

Absorption Lines ◽

Galactic Latitude ◽

High Galactic Latitude ◽

Interstellar Absorption

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Interstellar absorption lines in high-resolution IUE spectra of cataclysmic variables

The Astrophysical Journal ◽

10.1086/166971 ◽

1988 ◽

Vol 335 ◽

pp. 829 ◽

Cited By ~ 28

Author(s):

Christopher W. Mauche ◽

John C. Raymond ◽

France A. Cordova

Keyword(s):

High Resolution ◽

Cataclysmic Variables ◽

Absorption Lines ◽

Interstellar Absorption

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Magnesium Abundances in Planetary Nebulae and Interstellar Absorption of Mg II λ2800 A

Symposium - International Astronomical Union ◽

10.1017/s007418090013829x ◽

1989 ◽

Vol 131 ◽

pp. 217-217

Author(s):

D. Middlemass

Keyword(s):

High Resolution ◽

Planetary Nebulae ◽

Line Profiles ◽

Interstellar Absorption ◽

Magnesium Depletion ◽

Photo Ionization ◽

Line Strengths

SummaryHigh-resolution IUE images have provided line profiles of emission cut by interstellar absorption in the magnesium II lines λλ2795, 2802 A in nine objects. The underlying emission has been reconstructed in seven of these by fitting Gaussian profiles to the remaining line wings. Estimates of the ratio of intrinsic to observed emission ranging from 1.5 to 23 have been obtained. Photo-ionization models of IC 418, IC 4997 and NGC 2440 have been used to obtain Mg/H ratios from the corrected Mg II line strengths. The logarithmic magnesium abundances obtained were 7.6±0.12, 6.96±0.3 and 6.5±0.3 respectively. These results indicate that depletion of Mg into grains is less than previously thought and reduce the observed gradient in the magnesium abundance. The Mg depletion may be related to the C/O ratio within the nebula; carbon-rich planetary nebulae may have less magnesium depletion than those with C/0 < 1.

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INTERSTELLAR ABSORPTION TOWARDS THE NOVAE V339 DEL AND V5668 SGR

Revista Mexicana de Astronomía y Astrofísica ◽

10.22201/ia.01851101p.2019.55.02.02 ◽

2019 ◽

Vol 55 (2) ◽

pp. 141-149

Author(s):

D. Jack ◽

K.-P. Schröder

Keyword(s):

High Resolution ◽

Wavelength Range ◽

Absorption Feature ◽

Interstellar Absorption ◽

Absorption Features

We present a search and study of interstellar (IS) absorption features in the observed spectra of two Novae V339 Del and V5668 Sgr. We obtained high resolution spectra (R ≈ 20, 000) in the wavelength range between 3800 and 8800 Å of both novae with the TIGRE telescope. Common IS features of Na I and Ca II were identified in both novae, and the Ca II H and K features of Nova V339 Del show substructures, while a blueshifted absorption feature was found in the spectra of Nova V5668 Sgr. Absorption of K I was identified only in the spectra of Nova V5668 Sgr. The DIBs 6196, 6203, 6379, 6614 and 7562 were found in both novae, and in the spectra of Nova V5668 Sgr we could also identify the DIBs 5780, 5797 and 6660. We present the equivalent widths of all features and determined the column densities of Ca II, K I and hydrogen in the direction of Nova V5668 Sgr (log NCa II = 12.50, log NK I = 11.55, log NH = 18.5).

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