Recent Developments in the Work on Automated Spectral Classification by Means of Objective Prism Spectra

1994 ◽  
pp. 253-254
Author(s):  
V. Malyuto ◽  
T. Shvelidze
Keyword(s):  
Spectral Classification ◽  
Recent Developments ◽  
Objective Prism

scholarly journals Recent Developments in the Work on Automated Spectral Classification by Means of Objective Prism Spectra

1994 ◽  
Vol 161 ◽  
pp. 253-254
Author(s):  
V. Malyuto ◽  
T. Shvelidze
Keyword(s):  
Spectral Classification ◽  
Proper Motions ◽  
Stellar Spectra ◽  
Meridional Section ◽  
Spectrometric Data ◽  
Software Packages ◽  
The Galaxy ◽  
Recent Developments ◽  
Objective Prism

Some years ago a complex programme of studying the main meridional section of the Galaxy was started by astronomers of Kiev, Tartu, Abastumani and Vilnius Observatories with the aim of improving our knowledge of spatial and kinematic characteristics of stellar populations. Characteristic to the programme is the use of absolute proper motions of stars together with automated quantitative spectral classification for large stellar-statistical samples. The data are gathered in areas lying within 30° of the main meridional section of the Galaxy. To classify stars, objective prism stellar spectra of intermediate dispersion (166 å/mm at Hγ), obtained with the 70 cm meniscus telescope at the Abastumani Astrophysical Observatory, are used. The field diameter is 4° 50′, and the limiting photographical stellar magnitude is about 12 m . Our system of automated quantitative spectral classification of F-K stars applies criteria evaluation and is mainly based on two software packages: the SDR package for spectrometric data reduction and the CTATEC-2 package determining the linear regression model used for classification (Malyuto & Shvelidze 1989; Malyuto, Pelt & Shvelidze 1993).

An Extended Scheme of Spectral Classification for Objective Prism Spectra

1994 ◽  
pp. 255-257 ◽  
Author(s):  
P. Hantzios ◽  
E. Kontizas ◽  
F. Pasian ◽  
A. Dapergolas ◽  
M. Kontizas ◽  
...  
Keyword(s):  
Spectral Classification ◽  
Objective Prism

scholarly journals Contributions and Prospects for Spectral Classification of Stars with Objective Prism Techniques

1979 ◽  
Vol 47 ◽  
pp. 127-136
Author(s):  
E. K. Kharadze
Keyword(s):  
Galactic Structure ◽  
Spectral Classification ◽  
Missing Mass ◽  
Mass Problem ◽  
Important Stage ◽  
Objective Prism ◽  
Low Dispersion

The following topics will be discussed: a) A few historical comments; b) MK classification - the most important stage of classification work; c) Recently revealed peculiarity features and the problem of further differentiation of the classification scale; d) Classification work in the USSR; e) The role of classification results with respect to galactic structure studies; f) Low dispersion spectra and faint M-type stars and the missing mass problem; g) Extraterrestrial spectral observations: new promising means for research.

scholarly journals Objective Prism Spectral Classification at the Stockholm Observatory

1973 ◽  
Vol 50 ◽  
pp. 85-90 ◽  
Author(s):  
B. Nordström ◽  
A. Sundman
Keyword(s):  
Milky Way ◽  
Spectral Classification ◽  
Late Type ◽  
Objective Prism ◽  
Spectral Survey

As a result of the spectral survey at the Stockholm Observatory finding lists are prepared for early and late type stars in the Southern Milky Way. In order to make the lists more useful we present the principles of the stellar classification.

scholarly journals Preliminary Investigation of Quantitative Spectral Classification by Means of Objective-Prism Spectra Obtained with the Broerfelde Schmidt Telescope

1973 ◽  
Vol 50 ◽  
pp. 134-137
Author(s):  
J. V. Clausen
Keyword(s):  
Preliminary Investigation ◽  
Spectral Classification ◽  
Schmidt Telescope ◽  
Mean Error ◽  
Objective Prism ◽  
Hydrogen Lines

Different methods, used for measuring the strength of hydrogen lines in objective-prism spectra, are discussed and the parameters are compared with the photoelectric β-index. It is found that for A5V–G1V stars β can be given with a mean error of ±0.m020 (one spectrum).

scholarly journals A Test of the Accuracy of low Dispersion Objective Prism: Spectral Classification of Late-Type Stars Using DDO Photometry

1976 ◽  
Vol 72 ◽  
pp. 73-73
Author(s):  
J. J. Clariá ◽  
W. Osborn
Keyword(s):  
Band System ◽  
Class I ◽  
Spectral Features ◽  
Spectral Classification ◽  
Late Type ◽  
Intermediate Band ◽  
Metal Abundance ◽  
Objective Prism ◽  
Low Dispersion

A test has been made of the reliability of the multidimensional classification of late-type stars from low dispersion objective prism plates recently attempted by Stock and Wroblewski. Such classification at low dispersion is difficult due to the problem of separating the effects of luminosity from those of abnormal metal abundance. A sample of the stars classified by Stock and Wroblewski as metal weak (pec) and of those classified as luminous stars (class I) were observed using the DDO intermediate-band system. The photometry shows that the stars classified as pec are indeed population II giants, of low metal abundance ([Fe/H] < −1.0). The stars classified as I, however, were found in general not to be true supergiants but rather a mixture of various types of giants, such as CN strong stars, with spectral features that resemble, in one way or another, those of higher luminosity stars.

45. Spectral Classifications and Multi-Band Colour Indices

1973 ◽  
Vol 15 (1) ◽  
pp. 697-716 ◽  
Author(s):  
B. E. Westerlund
Keyword(s):  
Spectral Lines ◽  
General Tendency ◽  
Spectral Classification ◽  
Visual Classification ◽  
The Past ◽  
Objective Prism ◽  
Colour Indices ◽  
Multi Band

During the past three years there has been much activity in the field of spectral classification by photographic and photoelectric techniques. The general tendency of the spectral classification has been one of refinement of the criteria applied in visual classification, the more frequent appearance of criteria based on equivalent widths measured in higher-dispersion spectra and the use of narrowband photometry on individual often rather weak spectral lines. In the area of objective prism classification important extensive programmes are under way at many observatories. Here, the increased interest in and importance of automation of data available on spectral plates is perhaps most obvious.

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