III/23B MK Classification for OB Stars (Lesh 1968)
MK Classification for OB Stars
Lesh J.R.
<Astrophys. J. Suppl. Ser. 17, 371, (1968)>
=1968ApJS...17..371L 1968ApJS...17..371L
ADC_Keywords: MK spectral classification ; Stars, OB ; Spectral types
Description:
The catalog is a compilation of MK spectral types published in the
paper, "The kinematics of the Gould Belt: An Expanding Group?"
(Rountree Lesh 1968). Spectral types were determined for 464 stars of
Henry Draper type B5 and earlier, brighter than 6.5 visual magnitude
and higher than -20 degrees in declination. The spectra were
classified by the author using plates taken with the Yerkes 40-inch
refractor and MK spectrograph. The catalog contains HR, HD numbers,
MK types with temperature classes, subclasses, luminosity classes and
peculiarities, and remarks.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
catalog.dat 28 464 Catalog Data
remarks.dat 80 41 Remarks
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Byte-by-byte Description of file: catalog.dat
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Bytes Format Units Label Explanations
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1-4 I4 --- HR *? BS = HR number
6-11 I6 --- HD *HD number
13-16 A4 --- MKtemp *Temperature class and subclass (MK type)
18-24 A7 --- MKlum *Luminosity, peculiarities, etc. (MK type)
28 A1 --- rem *Remarks flag
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Note on HR:
BS = HR number is the number from the Yale Catalogue of Bright Stars
(Hoffleit 1964; see Cat. V/50).
Note on HD:
Number from The Henry Draper Catalogue (Cannon and Pickering 1918-1924;
see Cat. III/135)
Note on MKtemp:
Spectral type classified in the MK system.
Note on MKlum:
Spectral type classified in the MK system. Peculiarity codes include a new
classification scheme for the Be stars, assignment having been made based
upon the emission lines subsequent to MK spectral type and luminosity class
assignment based on absorption lines alone. The following notation is used
for the emission parameter:
e1 No overt hydrogen emission. Prototypes 66 Oph, 1H Cam. The H-beta
absorption line is partially or completely filled in, but is not
reversed. H-gamma may also show some filling in. The Fe II lines are
usually absent.
e1+ Prototype 48 Per. H-beta has a narrow emission core while remaining
predominantly an absorption line.
e2 H-beta in emission. Prototypes psi Per, 120 Tau. H-beta is an
emission line. H-gamma is also filled in but is not reversed, while
the other Balmer lines are not affected. The Fe II lines are often,
but not always, present.
e2+ Prototype HD 45995. H-gamma shows a narrow emission core and the higher
Balmer lines are slightly filled in. The Fe II lines are usually rather
marked.
e3 Complete hydrogen emission spectrum. Prototypes 11 Cam, HD 58050.
H-beta is an emission line and the higher Balmer lines, at least
through H-epsilon, have emission cores. The Fe II lines are usually
present, except in the earliest spectral types, but they do not
dominate the spectrum.
e3+ Prototype HD 41335. The Fe II lines are more prominent than at e3, but
the hydrogen emission strength is less than at e4.
e4 The extreme Be stars. Prototype chi Oph. There is intense emission in
all the Balmer lines, plus very strong Fe II lines (except in the
earliest types). This group is similar to the Bex class discussed by
Schild (1966).
Note on rem:
An asterisk (*) denotes that remarks are present in remarks of the
catalog.
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Byte-by-byte Description of file: remarks.dat
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Bytes Format Units Label Explanations
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1-6 I6 --- HD *HD number
8-80 A73 --- rem * Text of remarks
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Note on HD:
HD number of the star in The Henry Draper Catalogue (Cannon and Pickering
1918-1924). This field is repeated for continuation lines.
Note on rem:
Remarks in free text (upper and lower case) form. Bytes 1-6 are repeated
in case of multi-line comment.
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Remarks and Modifications:
The machine-readable table MK Classification of OB Stars was received from
the Centre de Donnees Astronomiques de Strasbourg on 5 April 1977. As
received, the catalog consisted of HR numbers and spectral types with no
spacing. The spectral types were recorded in all upper case characters as in
the published table, except that peculiarities such as "SHELL", indicated by
the notes to Table 4 in the published paper, had been added to the types
themselves. The following modifications and additions to the
machine-readable edition were made at the ADC:
1. Stars are identified by their HD numbers in the original publication
(Rountree Lesh 1968), but the machine-readable catalog had only HR
identifiers when received. A program was written to search the Yale
Catalogue of Bright Stars (BSC3) (Hoffleit 1964) to retrieve HD numbers and
insert them into the file. (The 1964 catalog was used because that version
was cited in the MK classification work.) The same program reformatted the
data to spread them a bit for improved readability. The HD numbers were
proofread against the published table and an erroneous HR entry was found
and corrected. One HD star not in the BSC3 had been omitted from the
machine version -- it was added.
2. The spectral-type notation was modified to upper and lower case to match
the standard notation. All spectral types were proofread against the
published table and corrections were made so that the information agrees
exactly.
3. The notes to Table 4 of the published paper were keyed into a file and
added to the machine version. Asterisk flags were added to the data file in
byte 28 to indicate the presence of a remark.
4. Several duplicate records were found and eliminated. There are seven
stars in the published paper whose spectral types are not given; these had
been omitted in the machine version as received, but were added so that all
stars in the original table (and thus discussed in the paper) are now
included.
References:
Cannon, A. J. and Pickering, E. C. 1918-1924, Ann. Astron. Obs. Harvard
College 91-99 (HD). (catalog III/135)
Hoffleit, D. 1964, Yale Catalogue of Bright Stars (New Haven: Yale
University Observatory). (catalog V/50)
Rountree Lesh, J. 1968, Astrophys. J. Suppl. 17, 371. =1968ApJS...17..371L 1968ApJS...17..371L
Schild, R. E. 1966, Astrophys. J. 146, 142. =1966ApJ...146..142S 1966ApJ...146..142S
(End) C.-H. Joseph Lyu [Hughes STX/NASA] 22-Jun-1995