J/ApJ/446/300 Classification of NIR spectra of A Stars (Weaver+ 1995)
Neural network classification of the near-infrared spectra of A-type stars
Weaver W.B., Torres-Dodgen A.V.
<Astrophys. J. 446, 300 (1995)>
=1995ApJ...446..300W 1995ApJ...446..300W
ADC_Keywords: Stars, A-type ; Spectrophotometry
Keywords: atlases - dust, extinction - infrared: stars -
stars: fundamental parameters - techniques: spectroscopic
Abstract:
We present an atlas of near-infrared (NIR) spectra of A stars for
luminosity classes Ia through V in the 15 A resolution system
described by Torres-Dodgen and Weaver 1993 III/181 and
demonstrate an accurate method to automatically classify A stars on
this system. Using equivalent widths, artificial neural networks
(ANNs) can classify these spectra to an accuracy of 0.4 types
(subclasses) in temperature and 0.15 classes in luminosity. Using the
spectrum, with no manual intervention except wavelength registration,
ANNs can classify these spectra with an accuracy comparable to that of
2A resolution MK classification: 0.5 types in temperature and 0.35
classes in luminosity. In addition, ANNs can concurrently determine
reddening to an accuracy of 0.05 in E(B-V). We demonstrate that this
NIR-ANN spectral classification system has the primary properties
needed for automated classification surveys: it is based in the most
efficient spectral region of modern silicon-based detectors, it
requires low resolution (15A) spectra to achieve sub-classification
box accuracy, it can produce two dimensional classifications at least
as accurate as those by expert human classifiers, it is relatively
insensitive to interstellar reddening and can accurately determine the
reddening, it can identify and classify composite spectra, it degrades
slowly with decreasing signal-to-noise ratio, and it requires a
minimum of human interaction at all stages of the process.
Description:
The tables contain the flux data used to make figures 1-5 in the
printed paper. The units of the flux columns are log(F_lambda),
F_lambda in mW/m2/(0.1nm). Field labels for the flux values are keyed
to the spectral type, in accordance with the labels in the figures.
When fluxes are given for more than one star of a given type, a
trailing "1", "2", etc. are appended to the label, however, this is
not part of the spectral type. The star identification is given in the
"Explanations."
Objects:
----------------------------------------------------------
RA (2000) DE Designation(s)
----------------------------------------------------------
11 53 49.2 +53 41 40 HR 4554 = HD 103287
18 36 55.4 +38 46 47 HR 7001 = HD 172167 = Vega
06 26 39.6 -01 30 25 HR 2324 = HD 45320
07 16 14.6 -15 35 07 HR 2758 = HD 56405
11 49 05.2 +14 34 25 HR 4534 = HD 102647
22 57 37.7 -29 37 12 HR 8728 = HD 216956
01 54 38.0 +20 48 34 HR 553 = HD 11636
13 25 12.7 +54 59 18 HR 5062 = HD 116842
09 16 11.0 +54 01 16 HR 3662 = HD 79439
08 26 27.3 -03 59 12 HR 3321 = HD 71297
21 38 31.5 +05 46 16 HR 8270 = HD 205924
01 24 01.8 -08 00 24 HR 401 = HD 8511
15 34 40.7 +26 42 57 HR 5793 = HD 139006
06 37 42.5 +16 24 00 HR 2421 = HD 47105
10 17 06.5 +42 54 54 HR 4033 = HD 89021
22 55 13.3 +08 48 57 HR 8717 = HD 216735
15 46 11.0 +15 25 21 HR 5867 = HD 141003
05 07 51.2 -05 05 07 HR 1666 = HD 33111
11 14 05.9 +20 31 32 HR 4357 = HD 97603
01 25 46.9 +60 14 10 HR 403 = HD 8538
02 09 31.9 +34 59 16 HR 622 = HD 13161
11 00 44.9 +06 06 06 HR 4294 = HD 95382
08 59 14.6 +48 02 41 HR 3569 = HD 76644
22 21 38.8 -01 23 15 HR 8518 = HD 212061
14 04 23.7 +64 22 32 HR 5291 = HD 123299
20 47 40.3 -09 29 43 HR 7950 = HD 198001
07 18 31.9 +49 27 53 HR 2751 = HD 56169
15 20 43.8 +71 50 01 HR 5735 = HD 137422
10 43 02.2 +26 19 35 HR 4189 = HD 92769
08 37 46.8 +19 16 03 HD 73210
04 28 39.3 +15 52 16 HR 1412 = HD 28319
11 53 50.4 +00 33 07 HR 4555 = HD 103313
16 21 55.3 +19 09 09 HR 6095 = HD 147547
00 36 27.2 +60 19 35 HR 146 = HD 3283
16 20 38.1 -24 10 09 HR 6081 = HD 147084
17 37 36.1 -15 34 16 HR 6562 = HD 159877
10 07 19.9 +16 45 46 HR 3975 = HD 87737
02 13 41.5 +58 33 39 HR 641 = HD 13476
16 30 29.8 -07 30 53 HR 6144 = HD 148743
03 29 54.8 +58 52 44 HR 1040 = HD 21389
20 41 25.8 +45 16 49 HR 7924 = HD 197345
18 02 31.6 -22 54 20 HD 164514
05 01 58.1 +43 49 24 HR 1605 = HD 31964
----------------------------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
fig1.dat 138 512 Flux data for figure 1, A V stars
fig2.dat 127 512 Flux data for figure 2, A IV stars
fig3.dat 116 512 Flux data for figure 3, A III stars
fig4.dat 72 512 Flux data for figure 4, A II, Ib, Iab stars
fig5.dat 50 512 Flux data for figure 5, A Ia stars
--------------------------------------------------------------------------------
See also:
III/181 : Near Infrared Spectra of Normal Stars (Torres-Dodgen+ 1993)
Byte-per-byte description of file: fig1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 F6.1 0.1nm Lambda Wavelength
8- 17 F10.5 10mW/m2/nm logF(A0_Va)1 HR 4554 = HD 103287 flux
19- 28 F10.5 10mW/m2/nm logF(A0_Va)2 Vega = HD 172167 flux
30- 39 F10.5 10mW/m2/nm logF(A1_Va) HR 2324 = HD 45320 flux
41- 50 F10.5 10mW/m2/nm logF(A2_Va) HR 2758 = HD 56405 flux
52- 61 F10.5 10mW/m2/nm logF(A3_Va)1 HR 4534 = HD 102647 flux
63- 72 F10.5 10mW/m2/nm logF(A3_Va)2 HR 8728 = HD 216956 flux
74- 83 F10.5 10mW/m2/nm logF(A4_V) HR 553 = HD 11636 flux
85- 94 F10.5 10mW/m2/nm logF(A5_Vn) HR 5062 = HD 116842 flux
96-105 F10.5 10mW/m2/nm logF(A6_V) HR 3662 = HD 79439 flux
107-116 F10.5 10mW/m2/nm logF(A7_V) HR 3321 = HD 71297 flux
118-127 F10.5 10mW/m2/nm logF(A8_Vn) HR 8270 = HD 205924 flux
129-138 F10.5 10mW/m2/nm logF(A9_V) HR 401 = HD 8511 flux
--------------------------------------------------------------------------------
Byte-per-byte description of file: fig2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 F6.1 0.1nm Lambda Wavelength
8- 17 F10.5 10mW/m2/nm logF(A0IV) HR 5793 = HD 139006 flux
19- 28 F10.5 10mW/m2/nm logF(A1IVs) HR 2421 = HD 47105 flux
30- 39 F10.5 10mW/m2/nm logF(A1IV)1 HR 4033 = HD 89021 flux
41- 50 F10.5 10mW/m2/nm logF(A1IV)2 HR 8717 = HD 216735 flux
52- 61 F10.5 10mW/m2/nm logF(A2IV) HR 5867 = HD 141003 flux
63- 72 F10.5 10mW/m2/nm logF(A3IV) HR 1666 = HD 33111 flux
74- 83 F10.5 10mW/m2/nm logF(A4IV) HR 4357 = HD 97603 flux
85- 94 F10.5 10mW/m2/nm logF(A5IV)1 HR 403 = HD 8538 flux
96-105 F10.5 10mW/m2/nm logF(A5IV)2 HR 622 = HD 13161 flux
107-116 F10.5 10mW/m2/nm logF(A6IV) HR 4294 = HD 95382 flux
118-127 F10.5 10mW/m2/nm logF(A7IV) HR 3569 = HD 76644 flux
--------------------------------------------------------------------------------
Byte-per-byte description of file: fig3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 F6.1 0.1nm Lambda Wavelength
8- 17 F10.5 10mW/m2/nm logF(B9.5III-IV) HR 8518 = HD 212061 flux
19- 28 F10.5 10mW/m2/nm logF(A0III) HR 5291 = HD 123299 flux
30- 39 F10.5 10mW/m2/nm logF(A1III-) HR 7950 = HD 198001 flux
41- 50 F10.5 10mW/m2/nm logF(A2III) HR 2751 = HD 56169 flux
52- 61 F10.5 10mW/m2/nm logF(A3III) HR 5735 = HD 137422 flux
63- 72 F10.5 10mW/m2/nm logF(A4III) HR 4189 = HD 92769 flux
74- 83 F10.5 10mW/m2/nm logF(A5III) HD 73210 flux
85- 94 F10.5 10mW/m2/nm logF(A7III) HR 1412 = HD 28319 flux
96-105 F10.5 10mW/m2/nm logF(A8III) HR 4555 = HD 103313 flux
107-116 F10.5 10mW/m2/nm logF(A9IIIb) HR 6095 = HD 147547 flux
--------------------------------------------------------------------------------
Byte-per-byte description of file: fig4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 F6.1 0.1nm Lambda Wavelength
8- 17 F10.5 10mW/m2/nm logF(A3II) HR 146 = HD 3283 flux
19- 28 F10.5 10mW/m2/nm logF(A5II) HR 6081 = HD 147084 flux
30- 39 F10.5 10mW/m2/nm logF(A7II-) HR 6562 = HD 159877 flux
41- 50 F10.5 10mW/m2/nm logF(A0Ib) HR 3975 = HD 87737 flux
52- 61 F10.5 10mW/m2/nm logF(A3Iab) HR 641 = HD 13476 flux
63- 72 F10.5 10mW/m2/nm logF(A7Ib) HR 6144 = HD 148743 flux
--------------------------------------------------------------------------------
Byte-per-byte description of file: fig5.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 F6.1 0.1nm Lambda Wavelength
8- 17 F10.5 10mW/m2/nm logF(A0Ia) HR 1040 = HD 21389 flux
19- 28 F10.5 10mW/m2/nm logF(A2Ia) HR 7924 = HD 197345 flux
30- 39 F10.5 10mW/m2/nm logF(A3Ia) HD 164514 flux
41- 50 F10.5 10mW/m2/nm logF(A9Ia) HR 1605 = HD 31964 flux
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Origin: AAS CD-ROM series, Volume 5, 1995 Lee Brotzman [ADS] 07-Oct-95
(End) [CDS] 29-Jan-1996