Analysis for fluorine by projecting the entire arc on the spectrograph slit

There are certain visual double stars which, when close to a node of their relative orbit, should have enough radial velocity difference (10-20 km/s) that the spectra of the two component stars will appear resolved on high-dispersion spectrograms (5 Å/mm or less) obtainable by use of modern coudé and solar spectrographs on bright stars. Both star images are then recorded simultaneously on the spectrograph slit, so that two stellar components will appear on each spectrogram.

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Exploring short period oscillations in filaments

Proceedings of the International Astronomical Union ◽

10.1017/s1743921308014853 ◽

2007 ◽

Vol 3 (S247) ◽

pp. 178-181 ◽

Cited By ~ 1

Author(s):

D. Y. Kolobov ◽

N. I. Kobanov ◽

S. A. Chupin

Keyword(s):

Data Reduction ◽

High Frequency ◽

Entrance Slit ◽

Doppler Velocity ◽

High Frequencies ◽

Spectrograph Slit ◽

High Frequency Oscillations ◽

Short Period ◽

False Signal ◽

Image Shifting

AbstractThe authors analyse sources of false Doppler velocity signals of high frequencies (10 mHz and higher) in observations of filaments. In ground-based observations, spectrograph noise and image shifting at the spectrograph entrance slit are the main causes of the false signal. It is shown that using differential methods and telluric lines as reference lines significantly reduces the influence of the first factor. Periodical image shifting along the spectrograph slit can be compensated for during data reduction. In some cases detected high-frequency oscillations appear to be real.

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Opacity Broadening as a Density Diagnostic for Spot Spectroscopy

International Astronomical Union Colloquium ◽

10.1017/s0252921100085869 ◽

1984 ◽

Vol 86 ◽

pp. 247-250

Author(s):

J.P. Apruzese

Keyword(s):

Direction Parallel ◽

Spectrograph Slit ◽

Novel Technique ◽

Original Target

Recently, a novel technique known as spot spectroscopy has been developed for use in diagnosis of laser-produced plasmas. This method involves the implantation of tracer microdots (circular or rectangular) of material in laser targets whose composition and size (typically about 100 μm) are known. Aluminum has been a popular choice since its K-shell lines are readily produced; however, any element appropriate to the experiment may be chosen. A major advantage of this technique is that the plasma produced from each microdot is generally homogeneous in the direction parallel to the plane of the original target. Since the dots can be distinguished spectroscopically, the diagnosis of each spot is not subject to the ambiguities created by the presence of gradients. Gradients do exist in each blowoff tracer perpendicular to the target plane; however, it is possible to resolve spatially the cylindrical blowoff created by each dot with appropriate orientation of the spectrograph slit.

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A Lens to Supplant the Spectrograph Slit*

Journal of the Optical Society of America ◽

10.1364/josa.36.000164 ◽

1946 ◽

Vol 36 (3) ◽

pp. 164 ◽

Cited By ~ 1

Author(s):

Carl M. King

Keyword(s):

Spectrograph Slit

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Antarctica – a case for 3D-spectroscopy

Proceedings of the International Astronomical Union ◽

10.1017/s1743921307012355 ◽

2006 ◽

Vol 2 (14) ◽

pp. 707-708

Author(s):

Andreas Kelz

Keyword(s):

Atmospheric Dispersion ◽

Spectrograph Slit ◽

Dispersion Compensator ◽

Integral Field Spectroscopy ◽

Field Spectroscopy ◽

Integral Field

DS or Integral-Field Spectroscopy (IFS) provides multiple spectra for each point of a 2-D field, rather than along a narrow, 1-D spectrograph slit only. Therefore, IFS does not require very accurate telescope pointing, nor do pre-assumptions about slit or aperture sizes have to be made. It avoids any ‘slit-losses’ due to seeing or atmospheric dispersion, which eliminates the need for any parallactic alignment or a dispersion compensator (see Fig. 1).

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The Measurement of Radial-Velocity Differences Between the Components of Close Visual Binary Systems

International Astronomical Union Colloquium ◽

10.1017/s0252921100027524 ◽

1965 ◽

Vol 5 ◽

pp. 102-108

Author(s):

A. H. Batten ◽

J. M. Fletcher

Keyword(s):

Radial Velocity ◽

Binary Systems ◽

Line Profiles ◽

Spectrograph Slit ◽

Visual Binary ◽

The Difference ◽

Visual Binaries

AbstractThe value obtained for the difference in radial velocity between components of a visual binary that is unresolved on the spectrograph slit appears to depend, sometimes, on whether the measurement is made visually with a microscope or by means of an oscilloscopic setting device. This apparent dependence has been confirmed by measurement of artificially produced double-lined spectrograms, and disappears for line pairs separated by more than 1.5 or 2 times the half-widths of their components. The dependence arises from blending of the two line profiles. There is some evidence that the results obtained from visual measures are affected by the scale of the image being measured. For this reason, oscilloscope measures are probably to be preferred; although their errors are sometimes larger, they seem to be more consistent. Errors arising from this sort of blending are not sufficient to explain measures of relative radial velocity of the components of some visual binaries, that differ widely from the predictions made from the visual orbits.

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Spectroscopic Observations of Visual Double Stars

International Astronomical Union Colloquium ◽

10.1017/s0252921100502620 ◽

1971 ◽

Vol 5 ◽

pp. 109-111

Author(s):

Frederick R. West

Keyword(s):

Radial Velocity ◽

High Dispersion ◽

Velocity Difference ◽

Spectrograph Slit ◽

Spectroscopic Observations ◽

Double Stars ◽

Visual Double Stars ◽

Relative Orbit ◽

Two Component ◽

Star Images

There are certain visual double stars which, when close to a node of their relative orbit, should have enough radial velocity difference (10-20 km/s) that the spectra of the two component stars will appear resolved on high-dispersion spectrograms (5 Å/mm or less) obtainable by use of modern coude and solar spectrographs on bright stars. Both star images are then recorded simultaneously on the spectrograph slit, so that two stellar components will appear on each spectrogram.

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On the Rotational Velocity of Fine Solar Structures Deduced from the Inclination to the Direction of Dispersion of Their Spectral Streaks

International Astronomical Union Colloquium ◽

10.1017/s025292110006557x ◽

1979 ◽

Vol 44 ◽

pp. 242-245 ◽

Cited By ~ 1

Author(s):

B. Rompolt ◽

S. Mzyk

Keyword(s):

Rotational Velocity ◽

Spectrograph Slit ◽

Observational Material

Observational material indicates that matter in some streamers and knots of prominences rotates (Rompolt, 1975a). We would like to propose a method which enables evaluation of the rate of rotation of such structures from their spectral streaks inclined to the direction of dispersion. These considerations concern fine prominence structures, the image of which is comparable with the width of the spectrograph slit. The matter in these structures is assumed to rotate as in a solid rod.

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