J/ApJ/774/72 Measurements of 19 DIBs and 8 other interstellar lines (Kos+, 2013)
Properties of diffuse interstellar bands at different physical conditions of
the interstellar medium.
Kos J., Zwitter T.
<Astrophys. J., 774, 72 (2013)>
=2013ApJ...774...72K 2013ApJ...774...72K
ADC_Keywords: Interstellar medium ; Equivalent widths
Keywords: astrochemistry - dust, extinction - ISM: lines and bands -
local interstellar matter
Abstract:
Diffuse interstellar bands (DIBs) can trace different conditions of
the interstellar medium (ISM) along the sightline toward the observed
stars. A small survey was made in optical wavelengths, producing
high-resolution and high signal-to-noise spectra. We present
measurements of 19 DIBs' properties in 50 sightlines toward hot stars,
distributed at a variety of galactic coordinates and interstellar
reddening. Equivalent widths were obtained by fitting asymmetric
Gaussian and variable continua to DIBs. Conditions of the ISM were
calculated from eight atomic and molecular interstellar lines. Two
distinctly different types of DIBs were identified by carefully
comparing correlation coefficients between DIBs and reddening and by
different behavior in UV-shielded (ζ) and nonshielded (σ)
sightlines. A ratio of DIBs at 5780Å and 5797Å proved to be
reliable enough to distinguish between two different sightline types.
Based on the linear relations between DIB equivalent width and
reddening for σ and ζ sightlines, we divide DIBs into type
I (where both linear relations are similar) and type II (where they
are significantly different). The linear relation for ζ type
sightlines always shows a higher slope and larger x-intercept
parameter than the relation for σ sightlines. Scatter around the
linear relation is reduced after the separation, but it does not
vanish completely. This means that UV shielding is the dominant factor
of the DIB equivalent width versus reddening relation shape for ζ
sightlines, but in σ sightlines other physical parameters play a
major role. No similar dependency on gas density, electron density, or
turbulence was observed. A catalog of all observed interstellar lines
is made public.
Description:
We measure profiles of 19 diffuse interstellar bands (DIBs) together
with lines of CaI, CaII, NaI, CH, CH+, and CN in spectra of 50 hot
stars obtained with the 1.82m telescope and an echelle spectroscope of
the Asiago observatory. The spectral range covered is
3700Å-7300Å, with the resolution power of 23000 and peak SNR of
300 or more. DIBs' profiles are represented by their central
wavelengths, FWHMs, asymetries, and equivalent widths.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
stars.dat 60 50 Stellar data
table1.dat 1254 50 Parameters of interstellar lines
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Byte-by-byte Description of file: stars.dat
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Bytes Format Units Label Explanations
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1- 2 A2 --- --- [HD]
3- 8 I6 --- HD HD number of the star
10- 17 F8.4 deg GLON Galactic longitude (1)
19- 26 F8.4 deg GLAT Galactic latitude (1)
28- 34 A7 --- SpType MK spectral type (1)
36- 40 F5.3 mag Vmag [1.7/8.3] V magnitude (1)
42- 46 F5.3 mag E(B-V) Color excess (2)
48- 52 F5.3 kpc Dist ? Distance (3)
54- 56 A3 --- Obs Observing sessions (4)
58- 60 I3 --- SNR [380/610] Peak SNR
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Note (1): From Simbad.
Note (2): From various sources. See paper for explanation.
Note (3): From Neckel, T., et al., Bulletin d'Information du Centre de
Donnees Stellaires, Vol. 19, P. 61 (1980BICDS..19...61N 1980BICDS..19...61N).
Note (4): Observation sessions are:
1 = 2011-01-16;
2 = 2011-09-15 and 2011-09-16
3 = 2012-02-03 to 2012-02-06
4 = 2012-05-03 to 2012-05-05
5 = 2012-08-29 to 2012-09-05
6 = 2012-11-24 to 2012-11-26
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Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 2 A2 --- --- [HD]
3- 8 I6 --- HD HD number of star
10- 16 F7.2 0.1nm c(4428) ? Central wavelength of DIB 4428
18- 21 F4.2 0.1nm e_c(4428) ? Error of central wavelength of DIB 4428
23- 27 F5.1 0.1pm EW(4428) ? Equivalent width of DIB 4428
29- 32 F4.1 0.1pm e_EW(4428) ? Error of equivalent width of DIB 4428
34- 38 F5.3 0.1nm W(4428) ? Width (FWHM) of DIB 4428
40- 44 F5.3 0.1nm e_W(4428) ? Error of width (FWHM) of DIB 4428
46- 50 F5.2 --- a(4428) ? Asymmetry of DIB 4428 (5)
52- 55 F4.2 --- e_a(4428) ? Error of asymmetry of DIB 4428
57- 63 F7.2 0.1nm c(4726) ? Central wavelength of DIB 4726
65- 68 F4.2 0.1nm e_c(4726) ? Error of central wavelength of DIB 4726
70- 74 F5.1 0.1pm EW(4726) ? Equivalent width of DIB 4726
76- 79 F4.1 0.1pm e_EW(4726) ? Error of equivalent width of DIB 4726
81- 85 F5.3 0.1nm W(4726) ? Width (FWHM) of DIB 4726
87- 91 F5.3 0.1nm e_W(4726) ? Error of width (FWHM) of DIB 4726
93- 97 F5.2 --- a(4726) ? Asymmetry of DIB 4726 (5)
99- 102 F4.2 --- e_a(4726) ? Error of asymmetry of DIB 4726
104- 110 F7.2 0.1nm c(4762) ? Central wavelength of DIB 4762
112- 115 F4.2 0.1nm e_c(4762) ? Error of central wavelength of DIB 4762
117- 121 F5.1 0.1pm EW(4762) ? Equivalent width of DIB 4762
123- 126 F4.1 0.1pm e_EW(4762) ? Error of equivalent width of DIB 4762
128- 132 F5.3 0.1nm W(4762) ? Width (FWHM) of DIB 4762
134- 138 F5.3 0.1nm e_W(4762) ? Error of width (FWHM) of DIB 4762
140- 144 F5.2 --- a(4762) ? Asymmetry of DIB 4762 (5)
146- 149 F4.2 --- e_a(4762) ? Error of asymmetry of DIB 4762
151- 157 F7.2 0.1nm c(4964) ? Central wavelength of DIB 4964
159- 162 F4.2 0.1nm e_c(4964) ? Error of central wavelength of DIB 4964
164- 167 F4.1 0.1pm EW(4964) ? Equivalent width of DIB 4964
169- 172 F4.1 0.1pm e_EW(4964) ? Error of equivalent width of DIB 4964
174- 178 F5.3 0.1nm W(4964) ? Width (FWHM) of DIB 4964
180- 184 F5.3 0.1nm e_W(4964) ? Error of width (FWHM) of DIB 4964
186- 190 F5.2 --- a(4964) ? Asymmetry of DIB 4964 (5)
192- 195 F4.2 --- e_a(4964) ? Error of asymmetry of DIB 4964
197- 203 F7.2 0.1nm c(5512) ? Central wavelength of DIB 5512
205- 208 F4.2 0.1nm e_c(5512) ? Error of central wavelength of DIB 5512
210- 213 F4.1 0.1pm EW(5512) ? Equivalent width of DIB 5512
215- 217 F3.1 0.1pm e_EW(5512) ? Error of equivalent width of DIB 5512
219- 223 F5.3 0.1nm W(5512) ? Width (FWHM) of DIB 5512
225- 229 F5.3 0.1nm e_W(5512) ? Error of width (FWHM) of DIB 5512
231- 235 F5.2 --- a(5512) ? Asymmetry of DIB 5512 (5)
237- 240 F4.2 --- e_a(5512) ? Error of asymmetry of DIB 5512
242- 248 F7.2 0.1nm c(5545) ? Central wavelength of DIB 5545
250- 253 F4.2 0.1nm e_c(5545) ? Error of central wavelength of DIB 5545
255- 258 F4.1 0.1pm EW(5545) ? Equivalent width of DIB 5545
260- 263 F4.1 0.1pm e_EW(5545) ? Error of equivalent width of DIB 5545
265- 269 F5.3 0.1nm W(5545) ? Width (FWHM) of DIB 5545
271- 275 F5.3 0.1nm e_W(5545) ? Error of width (FWHM) of DIB 5545
277- 281 F5.2 --- a(5545) ? Asymmetry of DIB 5545 (5)
283- 286 F4.2 --- e_a(5545) ? Error of asymmetry of DIB 5545
288- 294 F7.2 0.1nm c(5705) ? Central wavelength of DIB 5705
296- 299 F4.2 0.1nm e_c(5705) ? Error of central wavelength of DIB 5705
301- 305 F5.1 0.1pm EW(5705) ? Equivalent width of DIB 5705
307- 311 F5.1 0.1pm e_EW(5705) ? Error of equivalent width of DIB 5705
313- 317 F5.3 0.1nm W(5705) ? Width (FWHM) of DIB 5705
319- 323 F5.3 0.1nm e_W(5705) ? Error of width (FWHM) of DIB 5705
325- 329 F5.2 --- a(5705) ? Asymmetry of DIB 5705 (5)
331- 334 F4.2 --- e_a(5705) ? Error of asymmetry of DIB 5705
336- 342 F7.2 0.1nm c(5780) ? Central wavelength of DIB 5780
344- 347 F4.2 0.1nm e_c(5780) ? Error of central wavelength of DIB 5780
349- 353 F5.1 0.1pm EW(5780) ? Equivalent width of DIB 5780
355- 358 F4.1 0.1pm e_EW(5780) ? Error of equivalent width of DIB 5780
360- 364 F5.3 0.1nm W(5780) ? Width (FWHM) of DIB 5780
366- 370 F5.3 0.1nm e_W(5780) ? Error of width (FWHM) of DIB 5780
372- 376 F5.2 --- a(5780) ? Asymmetry of DIB 5780 (5)
378- 381 F4.2 --- e_a(5780) ? Error of asymmetry of DIB 5780
383- 389 F7.2 0.1nm c(5797) ? Central wavelength of DIB 5797
391- 394 F4.2 0.1nm e_c(5797) ? Error of central wavelength of DIB 5797
396- 400 F5.1 0.1pm EW(5797) ? Equivalent width of DIB 5797
402- 404 F3.1 0.1pm e_EW(5797) ? Error of equivalent width of DIB 5797
406- 410 F5.3 0.1nm W(5797) ? Width (FWHM) of DIB 5797
412- 416 F5.3 0.1nm e_W(5797) ? Error of width (FWHM) of DIB 5797
418- 422 F5.2 --- a(5797) ? Asymmetry of DIB 5797 (5)
424- 427 F4.2 --- e_a(5797) ? Error of asymmetry of DIB 5797
429- 435 F7.2 0.1nm c(5850) ? Central wavelength of DIB 5850
437- 440 F4.2 0.1nm e_c(5850) ? Error of central wavelength of DIB 5850
442- 446 F5.1 0.1pm EW(5850) ? Equivalent width of DIB 5850
448- 450 F3.1 0.1pm e_EW(5850) ? Error of equivalent width of DIB 5850
452- 456 F5.3 0.1nm W(5850) ? Width (FWHM) of DIB 5850
458- 462 F5.3 0.1nm e_W(5850) ? Error of width (FWHM) of DIB 5850
464- 468 F5.2 --- a(5850) ? Asymmetry of DIB 5850 (5)
470- 473 F4.2 --- e_a(5850) ? Error of asymmetry of DIB 5850
475- 481 F7.2 0.1nm c(6090) ? Central wavelength of DIB 6090
483- 486 F4.2 0.1nm e_c(6090) ? Error of central wavelength of DIB 6090
488- 491 F4.1 0.1pm EW(6090) ? Equivalent width of DIB 6090
493- 496 F4.1 0.1pm e_EW(6090) ? Error of equivalent width of DIB 6090
498- 502 F5.3 0.1nm W(6090) ? Width (FWHM) of DIB 6090
504- 508 F5.3 0.1nm e_W(6090) ? Error of width (FWHM) of DIB 6090
510- 514 F5.2 --- a(6090) ? Asymmetry of DIB 6090 (5)
516- 519 F4.2 --- e_a(6090) ? Error of asymmetry of DIB 6090
521- 527 F7.2 0.1nm c(6196) ? Central wavelength of DIB 6196
529- 532 F4.2 0.1nm e_c(6196) ? Error of central wavelength of DIB 6196
534- 537 F4.1 0.1pm EW(6196) ? Equivalent width of DIB 6196
539- 541 F3.1 0.1pm e_EW(6196) ? Error of equivalent width of DIB 6196
543- 547 F5.3 0.1nm W(6196) ? Width (FWHM) of DIB 6196
549- 553 F5.3 0.1nm e_W(6196) ? Error of width (FWHM) of DIB 6196
555- 559 F5.2 --- a(6196) ? Asymmetry of DIB 6196 (5)
561- 564 F4.2 --- e_a(6196) ? Error of asymmetry of DIB 6196
566- 572 F7.2 0.1nm c(6202) ? Central wavelength of DIB 6202
574- 577 F4.2 0.1nm e_c(6202) ? Error of central wavelength of DIB 6202
579- 583 F5.1 0.1pm EW(6202) ? Equivalent width of DIB 6202
585- 587 F3.1 0.1pm e_EW(6202) ? Error of equivalent width of DIB 6202
589- 593 F5.3 0.1nm W(6202) ? Width (FWHM) of DIB 6202
595- 599 F5.3 0.1nm e_W(6202) ? Error of width (FWHM) of DIB 6202
601- 605 F5.2 --- a(6202) ? Asymmetry of DIB 6202 (5)
607- 610 F4.2 --- e_a(6202) ? Error of asymmetry of DIB 6202
612- 618 F7.2 0.1nm c(6270) ? Central wavelength of DIB 6270
620- 623 F4.2 0.1nm e_c(6270) ? Error of central wavelength of DIB 6270
625- 629 F5.1 0.1pm EW(6270) ? Equivalent width of DIB 6270
631- 634 F4.1 0.1pm e_EW(6270) ? Error of equivalent width of DIB 6270
636- 640 F5.3 0.1nm W(6270) ? Width (FWHM) of DIB 6270
642- 646 F5.3 0.1nm e_W(6270) ? Error of width (FWHM) of DIB 6270
648- 652 F5.2 --- a(6270) ? Asymmetry of DIB 6270 (5)
654- 657 F4.2 --- e_a(6270) ? Error of asymmetry of DIB 6270
659- 665 F7.2 0.1nm c(6379) ? Central wavelength of DIB 6379
667- 670 F4.2 0.1nm e_c(6379) ? Error of central wavelength of DIB 6379
672- 676 F5.1 0.1pm EW(6379) ? Equivalent width of DIB 6379
678- 681 F4.1 0.1pm e_EW(6379) ? Error of equivalent width of DIB 6379
683- 687 F5.3 0.1nm W(6379) ? Width (FWHM) of DIB 6379
689- 693 F5.3 0.1nm e_W(6379) ? Error of width (FWHM) of DIB 6379
695- 699 F5.2 --- a(6379) ? Asymmetry of DIB 6379 (5)
701- 704 F4.2 --- e_a(6379) ? Error of asymmetry of DIB 6379
706- 712 F7.2 0.1nm c(6445) ? Central wavelength of DIB 6445
714- 717 F4.2 0.1nm e_c(6445) ? Error of central wavelength of DIB 6445
719- 722 F4.1 0.1pm EW(6445) ? Equivalent width of DIB 6445
724- 726 F3.1 0.1pm e_EW(6445) ? Error of equivalent width of DIB 6445
728- 732 F5.3 0.1nm W(6445) ? Width (FWHM) of DIB 6445
734- 738 F5.3 0.1nm e_W(6445) ? Error of width (FWHM) of DIB 6445
740- 744 F5.2 --- a(6445) ? Asymmetry of DIB 6445 (5)
746- 749 F4.2 --- e_a(6445) ? Error of asymmetry of DIB 6445
751- 757 F7.2 0.1nm c(6613) ? Central wavelength of DIB 6613
759- 762 F4.2 0.1nm e_c(6613) ? Error of central wavelength of DIB 6613
764- 768 F5.1 0.1pm EW(6613) ? Equivalent width of DIB 6613
770- 773 F4.1 0.1pm e_EW(6613) ? Error of equivalent width of DIB 6613
775- 779 F5.3 0.1nm W(6613) ? Width (FWHM) of DIB 6613
781- 785 F5.3 0.1nm e_W(6613) ? Error of width (FWHM) of DIB 6613
787- 791 F5.2 --- a(6613) ? Asymmetry of DIB 6613 (5)
793- 796 F4.2 --- e_a(6613) ? Error of asymmetry of DIB 6613
798- 804 F7.2 0.1nm c(6660) ? Central wavelength of DIB 6660
806- 809 F4.2 0.1nm e_c(6660) ? Error of central wavelength of DIB 6660
811- 814 F4.1 0.1pm EW(6660) ? Equivalent width of DIB 6660
816- 818 F3.1 0.1pm e_EW(6660) ? Error of equivalent width of DIB 6660
820- 824 F5.3 0.1nm W(6660) ? Width (FWHM) of DIB 6660
826- 830 F5.3 0.1nm e_W(6660) ? Error of width (FWHM) of DIB 6660
832- 836 F5.2 --- a(6660) ? Asymmetry of DIB 6660 (5)
838- 841 F4.2 --- e_a(6660) ? Error of asymmetry of DIB 6660
843- 849 F7.2 0.1nm c(7079) ? Central wavelength of DIB 7079
851- 854 F4.2 0.1nm e_c(7079) ? Error of central wavelength of DIB 7079
856- 860 F5.1 0.1pm EW(7079) ? Equivalent width of DIB 7079
862- 865 F4.1 0.1pm e_EW(7079) ? Error of equivalent width of DIB 7079
867- 872 F6.3 0.1nm W(7079) ? Width (FWHM) of DIB 7079
874- 878 F5.3 0.1nm e_W(7079) ? Error of width (FWHM) of DIB 7079
880- 884 F5.2 --- a(7079) ? Asymmetry of DIB 7079 (5)
886- 889 F4.2 --- e_a(7079) ? Error of asymmetry of DIB 7079
891- 897 F7.2 0.1nm c(5891) ? Central wavelength of NaI (5891)
899- 902 F4.2 0.1nm e_c(5891) ? Error of central wavelength of NaI (5891)
904- 909 F6.1 0.1pm EW(5891) ? Equivalent width of NaI (5891)
911- 914 F4.1 0.1pm e_EW(5891) ? Error of equivalent width of NaI (5891)
916- 920 F5.3 0.1nm W(5891) ? Width (FWHM) of NaI (5891)
922- 926 F5.3 0.1nm e_W(5891) ? Error of width (FWHM) of NaI (5891)
928- 930 F3.1 --- a(5891) ? Asymmetry of NaI (5891) (5)
932- 935 F4.2 --- e_a(5891) ? Error of asymmetry of NaI (5891)
937- 943 F7.2 0.1nm c(5897) ? Central wavelength of NaI (5897)
945- 948 F4.2 0.1nm e_c(5897) ? Error of central wavelength of NaI (5897)
950- 954 F5.1 0.1pm EW(5897) ? Equivalent width of NaI (5897)
956- 959 F4.1 0.1pm e_EW(5897) ? Error of equivalent width of NaI (5897)
961- 965 F5.3 0.1nm W(5897) ? Width (FWHM) of NaI (5897)
967- 971 F5.3 0.1nm e_W(5897) ? Error of width (FWHM) of NaI (5897)
973- 976 F4.2 --- a(5897) ? Asymmetry of NaI (5897) (5)
978- 981 F4.2 --- e_a(5897) ? Error of asymmetry of NaI (5897)
983- 989 F7.2 0.1nm c(4227) ? Central wavelength of CaI (4227)
991- 994 F4.2 0.1nm e_c(4227) ? Error of central wavelength of CaI (4227)
996- 999 F4.1 0.1pm EW(4227) ? Equivalent width of CaI (4227)
1001-1004 F4.1 0.1pm e_EW(4227) ? Error of equivalent width of CaI (4227)
1006-1010 F5.3 0.1nm W(4227) ? Width (FWHM) of CaI (4227)
1012-1016 F5.3 0.1nm e_W(4227) ? Error of width (FWHM) of CaI (4227)
1018-1020 F3.1 --- a(4227) ? Asymmetry of CaI (4227) (5)
1022-1025 F4.2 --- e_a(4227) ? Error of asymmetry of CaI (4227)
1027-1033 F7.2 0.1nm c(3934) ? Central wavelength of CaII (3934)
1035-1038 F4.2 0.1nm e_c(3934) ? Error of central wavelength of CaII(3934)
1040-1044 F5.1 0.1pm EW(3934) ? Equivalent width of CaII (3934)
1046-1049 F4.1 0.1pm e_EW(3934) ? Error of equivalent width of CaII (3934)
1051-1055 F5.3 0.1nm W(3934) ? Width (FWHM) of CaII (3934)
1057-1061 F5.3 0.1nm e_W(3934) ? Error of width (FWHM) of CaII (3934)
1063-1065 F3.1 --- a(3934) ? Asymmetry of CaII (3934) (5)
1067-1070 F4.2 --- e_a(3934) ? Error of asymmetry of CaII (3934)
1072-1078 F7.2 0.1nm c(3969) ? Central wavelength of CaII (3969)
1080-1083 F4.2 0.1nm e_c(3969) ? Error of central wavelength of CaII(3969)
1085-1089 F5.1 0.1pm EW(3969) ? Equivalent width of CaII (3969)
1091-1094 F4.1 0.1pm e_EW(3969) ? Error of equivalent width of CaII (3969)
1096-1100 F5.3 0.1nm W(3969) ? Width (FWHM) of CaII (3969)
1102-1106 F5.3 0.1nm e_W(3969) ? Error of width (FWHM) of CaII (3969)
1108-1112 F5.2 --- a(3969) ? Asymmetry of CaII (3969) (5)
1114-1117 F4.2 --- e_a(3969) ? Error of asymmetry of CaII (3969)
1119-1125 F7.2 0.1nm c(4300) ? Central wavelength of CH (4300)
1127-1131 F5.2 0.1nm e_c(4300) ? Error of central wavelength of CH (4300)
1133-1136 F4.1 0.1pm EW(4300) ? Equivalent width of CH (4300)
1138-1141 F4.1 0.1pm e_EW(4300) ? Error of equivalent width of CH (4300)
1143-1147 F5.3 0.1nm W(4300) ? Width (FWHM) of CH (4300)
1149-1153 F5.3 0.1nm e_W(4300) ? Error of width (FWHM) of CH (4300)
1155-1157 F3.1 --- a(4300) ? Asymmetry of CH (4300) (5)
1159-1162 F4.2 --- e_a(4300) ? Error of asymmetry of CH (4300)
1164-1170 F7.2 0.1nm c(4232) ? Central wavelength of CH+ (4232)
1172-1175 F4.2 0.1nm e_c(4232) ? Error of central wavelength of CH+ (4232)
1177-1180 F4.1 0.1pm EW(4232) ? Equivalent width of CH+ (4232)
1182-1185 F4.1 0.1pm e_EW(4232) ? Error of equivalent width of CH+ (4232)
1187-1192 F6.3 0.1nm W(4232) ? Width (FWHM) of CH+ (4232)
1194-1198 F5.3 0.1nm e_W(4232) ? Error of width (FWHM) of CH+ (4232)
1200-1202 F3.1 --- a(4232) ? Asymmetry of CH+ (4232) (5)
1204-1207 F4.2 --- e_a(4232) ? Error of asymmetry of CH+ (4232)
1209-1215 F7.2 0.1nm c(3874) ? Central wavelength of CN (3874)
1217-1220 F4.2 0.1nm e_c(3874) ? Error of central wavelength of CN (3874)
1222-1225 F4.1 0.1pm EW(3874) ? Equivalent width of CN (3874)
1227-1230 F4.1 0.1pm e_EW(3874) ? Error of equivalent width of CN (3874)
1232-1237 F6.3 0.1nm W(3874) ? Width (FWHM) of CN (3874)
1239-1243 F5.3 0.1nm e_W(3874) ? Error of width (FWHM) of CN (3874)
1245-1249 F5.2 --- a(3874) ? Asymmetry of CN (3874) (5)
1251-1254 F4.2 --- e_a(3874) ? Error of asymmetry of CN (3874)
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Note (5): the asymmetry index (in range [-1/+1]) is defined from the fitting
by 2 gaussians with different widths σ1 and σ2 as
a=(σ1-σ2)/(σ1+σ2)
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Acknowledgements:
Janez Kos, janez.kos(at)fmf.uni-lj.si
(End) J. Kos [Univ. of Ljubljana, Slovenia], P. Vannier [CDS] 30-Jun-2014