J/AZh/73/906 Energy distribution of main-sequence B stars (Knyazeva+, 1996)
On the normal energy distribution in stellar spectra: main-sequence B stars.
Knyazeva L.N., Kharitonov A.V.
<Astron. Zh. 73, 906 (1996)>
=1996AZh....73..906K 1996AZh....73..906K
=1996ARep...40..823K 1996ARep...40..823K
ADC_Keywords: Stars, OB ; Energy distributions
Description:
The normal spectral energy distribution in the spectra of
main-sequence B stars of five subclasses is presented. Spectral
classification and UBV photometry from the fourth edition of the BSC
and spectrophotometry from three extensive spectrophotometric catalogs
are used. The method of selecting unreddened stars is outlined. The
good agreement between the mean color indices in the UBV system
calculated for a sample of stars with spectrophotometry and for
considerably larger samples of unreddened stars of the corresponding
subclasses from the BSC confirms the reliability of the results
obtained.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table4.dat 39 88 Normal energy distributions
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See also:
III/186 : Energy distribution in stars at 320-760 nm (Knyazeva+, 1996)
V/50 : Bright Star Catalogue, 5th Revised Ed. (Hoffleit+, 1991)
J/AZh/73/67 : Energy distribution of G,K and M stars (Knyazeva+, 1996)
J/AZh/75/70 : Energy distribution of O9-B5 stars (Knyazeva+, 1998)
J/AZh/75/197 : Energy distribution of O5-O8 stars (Knyazeva+, 1998)
Table 1: Normal color indices for MS B5-B9.5 stars as described by
different authors and restrictions adopted for unreddened stars
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Authors and references
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[8] [9] [10] [11] [12] [13] [14] Boundary
SpCl values
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color indices
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B5V B-V -0.16 -0.21 -0.18 -O.15 -0.16 -0.17 -0.12
U-B -0.56 -0.59 -0.58 -0.57 -0.51
B6V B-V -0.17 -0.16 -0.12 -0.14 -0.15
U-B -0.51 -0.49 -0.50
B7V B-V -0.13 -0.15 -0.14 -0.10 -0.13 -0.13 -0.09
U-B -0.47 -0.44 -0.43 -0.43 -0.36
B8V B-V -0.09 -0.12 -0.12 -0.07 -0.05 -0.11 -0.10 -0.07
U-B -0.29 -0.36 -0.31 -0.36 -0.33 -0.25
B9V B-V -0.05 -0.08 -0.08 -0.04 -0.04 -0.07 -0.07 -0.06
U-B -0.16 -0.21 -0.19 -0.18 -0.19 -0.12
B9.5V B-V -0.03 -0.05 -0.06 -0.02 -0.04 -0.04 -0.04 0.00
U-B -0.08 -0.12 -0.14 -0.10 -0.10 -0.06
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References:
[8] Johnson & Morgan, 1953ApJ...117..313J 1953ApJ...117..313J
[9] Sharov, 1963AZh....40..900S 1963AZh....40..900S
[10] Serkowski, 1963ApJ...138.1035S 1963ApJ...138.1035S
[11] Gottlieb, 1969ApJ...157..611G 1969ApJ...157..611G
[12] Cowley et al., 1970AJ.....75..941C 1970AJ.....75..941C
[13] Fitzgerald, 1970A&A.....4..234F 1970A&A.....4..234F
[14] Straizhis, 1977, Mnogotsvetnaya fotometriya zvezd
(Multicolor stellar photometry), Vilnius: Mokslas Publishers.
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Table 2: Properties of the sample of stars
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B-V U-B
SP n max min mean max min mean
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Complete sample of stars
B5V 35 -0.12 -0.17 -0.140 -0.51 -0 65 -0.559
B7V 21 -0.09 -0.14 -0.111 -0.36 -0.50 -0.439
B8V 40 -0.07 -0.15 -0.097 -0.25 -0.51 -0.368
B9V 44 -0.06 -0.12 -0.079 -0.12 -0.45 -0.263
B9.5V 43 -0.00 -0.08 -0.043 -0.06 -0.24 -0.133
Sample of stars with spectrophotometry
B5V 9 -0.13 -0.15 -0.141 -0.51 -0.58 -0.556
B7V 5 -0.09 -0.14 -0.108 -0.36 -0.48 -0.428
B8V 8 -0.08 -0.15 -0.105 -0.25 -0.45 -0.361
B9V 9 -0.07 -0.10 -0.081 -0.19 -0.38 -0.276
B9.5V 13 0.00 -0.08 -0.042 -0.07 -0.17 -0.119
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Table 3: List of stars (BS number) used to derive the
normal energy distribution
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B5V B7V B8V B9V B9.5V B9.5V
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154 A 847 A 123 A,M 26 A 132 A 6779 A
1244 A 910 A 1088 P 1038 A,M 342 A 7773 P
1289 A 1399 A 1202 M 1070 M 522 A 8546 A
1839A,M 2223 M 1696 A 1705 A 708 A 8988 A
2198 M 3982 A,P 5685 A,M,P 1997 A 1621 P
3849 A,M 6079 A,M 5718 A 3268 A
7608 A,M 6281 A,M 7236 A,P 4386 A
8001 A,M,P 8634 A,M 7880 A 4468 A
8858 A 9048 A 4757 A
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 4 I4 0.1nm Lambda Wavelength
7-11 F5.3 --- B5V Spectral energy for B5V stars normalized
to 1.0 at 5475Å
14-18 F5.3 --- B7V Spectral energy for B7V stars normalized
to 1.0 at 5475Å
21-25 F5.3 --- B8V Spectral energy for B8V stars
normalized to 1.0 at 5475Å
28-32 F5.3 --- B9V Spectral energy for B9V stars normalized
to 1.0 at 5475Å
35-39 F5.3 --- B9.5V Spectral energy for B9.5V stars normalized
to 1.0 at 5475Å
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(End) Veta Avedisova [INASAN] 12-Apr-2001