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J/A+A/402/343   IR O I triplet, [O I] lines in F-K dwarfs/giants  (Takeda, 2003)

Oxygen line formation in late-F through early-K dwarfs/giants: Infrared O I triplet and [O I] lines. Takeda Y. <Astron. Astrophys. 402, 343 (2003)> =2003A&A...402..343T
ADC_Keywords: Stars, metal-deficient ; Abundances, peculiar ; Models, atmosphere Keywords: line: formation - radiative transfer - Galaxy: abundances - stars: late-type - stars: population II Abstract: In order to investigate the formation of O I 7771-5 and [O I] 6300/6363 lines, extensive non-LTE calculations for neutral atomic oxygen were carried out for wide ranges of model atmosphere parameters, which are applicable to early-K through late-F halo/disk stars of various evolutionary stages. The formation of the triplet O I lines was found to be well described by the classical two-level-atom scattering model, and the non-LTE correction is practically determined by the parameters of the line-transition itself without any significant relevance to the details of the oxygen atomic model. This simplifies the problem in the sense that the non-LTE abundance correction is essentially determined only by the line-strength (Wλ), if the atmospheric parameters of Teff, logg, and ξ are given, without any explicit dependence of the metallicity; thus allowing a useful analytical formula with tabulated numerical coefficients. On the other hand, our calculations lead to the robust conclusion that LTE is totally valid for the forbidden [O I] lines. Description: Table2 contains the results of non-LTE abundance corrections for each of the O I triplet lines (at 7771.94, 7774.17, and 7775.39 Å) computed on a large grid of models [Teff= 4500, 5000, 5500, 6000, 6500K, logg (cm/s2) = 1.0, 2.0, 3.0, 4.0, 5.0, and [Fe/H] = 0, -1, -2, -3] for the microturbulence values of 1, 2, and 3km/s. See Table 1 below for the adopted atomic data. Table 3 gives the numerical coefficients (a, b) used with the analytic formula, Δ=a*10b*Wλ_^, where Δ is the non-LTE abundance correction and Wλ the equivalent width), for evaluating the non-LTE correction, corresponding to each of the atmospheric models (combination of each Teff and logg). These data were computed for three values of the microturbulent velocity (ξ=1, 2, and 3km/s) for each of the three lines of the O I triplet (O I 7771.94, 7774.17, and 7775.39). The minimum and the maximum value of the equivalent-widths (in mÅ), used to established the coefficients, are also given. (These indicate the range of the Wλ values to which the formula with these coefficients can be applied.) Table7 contains the results of non-LTE abundance corrections for the O I 6158.2 line (blend of three components at 6158.149, 6158.172, 6158.187Å) computed on a large grid of models [Teff= 4500, 5000, 5500, 6000, 6500K, logg (cm/s2) = 1.0, 2.0, 3.0, 4.0, 5.0, and [Fe/H] = 0, -1] for the microturbulence values of 1, 2, and 3km/s. The blending of three components was correctly treated by synthesizing the spectrum in evaluating the equivalent width of the O I 6158 line as well as in deriving the abundance there from. See Table 1 below for the adopted atomic data. Table5: The data contained in each file are: 1. Published values in the corresponding literature which was adopted here Equivalent widths (for the O I 7771/7774/7775 lines and/or [O I] 6300/6363 lines) Atmospheric parameters (Teff, log g, xi, and [Fe/H]) 2. Results of the reanalysis: LTE abundance, non-LTE correction, final NLTE abundance (for each line) averaged [O/Fe]77 and [O/Fe]63 over available lines (for O I and [O I]) averaged non-LTE correction <Del>77 for the O I triplet lines. These data further form the basis of Fig. 8: Fig. 8a --> [Fe/H], [O/Fe]77, and [O/Fe]63; Fig. 8b --> [Fe/H] and <Del>77. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file stars.dat 80 266 Positions of stars in table5.dat (from Simbad) table2.dat 87 2700 Equivalent widths and NLTE correction of O I triplet lines (at 7771.94, 7774.17, and 7775.39Å) table3.dat 112 75 Coefficients (a, b) for O I 7771.94, 7774.17, and 7775.39Å table5.dat 192 334 Reanalysis of published data table7.dat 87 450 Equivalent widths and NLTE correction of O I at 6158.2Å
Byte-by-byte Description of file: stars.dat
Bytes Format Units Label Explanations
1- 12 A12 --- Star Star name 14- 29 A16 --- SName Simbad name when different of those in Star 31- 32 I2 h RAh Right ascension (J2000.0) 34- 35 I2 min RAm Right ascension (J2000.0) 37- 40 F4.1 s RAs Right ascension (J2000.0) 42 A1 --- DE- Declination sign (J2000.0) 43- 44 I2 deg DEd Declination (J2000.0) 46- 47 I2 arcmin DEm Declination (J2000.0) 49- 50 I2 arcsec DEs Declination (J2000.0) 54- 58 F5.2 mag Bmag B magnitude 60- 64 F5.2 mag Vmag V magnitude 66- 78 A13 --- SpType MK Spectral type
Table 1: Data of neutral oxygen lines adopted for abundance calculations. ----------------------------------------------------------------------------- RMT lambda (Å) chi (eV) loggf Gammar Gammas Gammaw ----------------------------------------------------------------------------- 1 7771.944 9.146 0.324 7.52 -5.55 -7.65* 1 7774.166 9.146 0.174 7.52 -5.55 -7.65* 1 7775.388 9.146 -0.046 7.52 -5.55 -7.65* .. 6300.304 0.000 -9.819 -2.17 -7.83* -8.13* .. 6363.776 0.020 -10.303 -2.17 -7.83* -8.13* 10 6158.149 10.741 -1.891 7.62 -3.96 -7.23* 10 6158.172 10.741 -1.031 7.62 -3.96 -7.23* 10 6158.187 10.741 -0.441 7.62 -3.96 -7.23* ----------------------------------------------------------------------------- Note: All data are were taken from Kurucz & Bell's (1995, CD-ROM No. 23) compilation as far as available. RMT is the Revised Multiplet Table (Moore, 1945, Princeton Obs. Contr. No. 20.) number Damping parameters are given in the last three columns: Gammar is the radiation damping constant, log(γrad). Gammae is the Stark damping width per electron density at 104K, log(γe/Ne) Gammaw is the van der Waals damping width per hydrogen density at 104K, log(γw/NH). *: Computed as default values in the Kurucz's WIDTH program (cf. Leusin, Topil'skaya, 1987Ap.....25..415L) Byte-by-byte Description of file: table2.dat table7.dat
Bytes Format Units Label Explanations
1- 8 A8 --- Code Model code (1) 10- 13 I4 K Teff Effective temperature 15- 17 F3.1 [cm/s+2] logg Surfcace gravity 19- 22 F4.1 [Sun] [Fe/H] Metalicity 24- 30 F7.2 0.1nm lambda Wavelength of the line 32- 34 F3.1 km/s xi Microturbulence velocity 36- 40 F5.1 --- [O/Fe]a Oxygen-to-iron logarithmic abundance ratio 42- 47 F6.3 --- Ainput Assigned oxygen abundance (G1) 50 A1 --- --- Left bracket (dummy) 52- 57 F6.2 0.1pm EW(LTE) LTE equivalent width 58 A1 --- --- Right bracket (dummy) 61- 66 F6.2 0.1pm EW(NLTE) NLTE equivalent width 68- 73 F6.3 --- A(NLTE) NLTE abundance (G1) (2) 75- 80 F6.3 --- A(LTE) LTE abundance (G1) (2) 82- 87 F6.3 --- Delta Non-LTE abundance correction (G1) (3)
Note (1): Model code tnngnnm1 format, where tnn represent the effective temperature, i.e., t45 ---> Teff=4500K t50 ---> Teff=5000K t55 ---> Teff=5500K t60 ---> Teff=6000K t65 ---> Teff=6500K gnn represents the log of gravity surface, i.e., g10 ---> log g=1.0 g20 ---> log g=2.0 g30 ---> log g=3.0 g40 ---> log g=4.0 g50 ---> log g=5.0 mn represents the metallicity [Fe/H], i.e., m0 ---> [Fe/H]= 0.0 m1 ---> [Fe/H]= -1.0 m2 ---> [Fe/H]= -2.0 m3 ---> [Fe/H]= -3.0 For example: t65g50m0 --> Teff=6500K log g=5.0 [Fe/H]= 0.0 [O/Fe] value assumed for NLTE calculation: [O/Fe]a = 0.00 for ??????m0 models [O/Fe]a =+0.50 for ??????m1, ??????m2, ??????m3 models The theoretical equivalent widths (LTE as well as NLTE) were evaluated for three input abundances [O/Fe]i = [O/Fe]a -0.3 = [O/Fe]a = [O/Fe]a +0.3 i.e., abundances were perturbed by ± 0.3 dex around the exact value) Note (2): A(NLTE) and A(LTE) are the abundances derived from W(NLTE) under the assumption of NLTE and LTE, respectively. Though A(NLTE) should be equal to Ainput in the strict sense, there are practically small discrepancy because of numerical problems. Note (3): The Delta is the NLTE correction defined as Delta = A(NLTE)-A(LTE).
Byte-by-byte Description of file: table3.dat
Bytes Format Units Label Explanations
1- 7 F7.2 0.1nm lambda Line wavelength 9- 13 I5 K Teff Adopted effective temperature 15- 18 F4.1 cm/s2 logg Adopted logarithmic surface gravity 21- 29 F9.6 --- a1 "a" value for xi=1km/s 32- 40 F9.6 --- b1 "b" value for xi=1km/s 43- 44 I2 0.1pm Wmin1 lower limit of the equivalent width range (for a1 and b1) 45 A1 --- --- [-] 46- 48 I3 0.1pm Wmax1 upper limit of the equivalent width range (for a1 and b1) 52- 60 F9.6 --- a2 "a" value for xi=2km/s 63- 71 F9.6 --- b2 "b" value for xi=2km/s 74- 75 I2 0.1pm Wmin2 lower limit of the equivalent width range (for a2 and b2) 76 A1 --- --- [-] 77- 79 I3 0.1pm Wmax2 upper limit of the equivalent width range (for a2 and b2) 83- 91 F9.6 --- a3 "a" value for xi=3km/s 94-102 F9.6 --- b3 "b" value for xi=3km/s 105-106 I2 0.1pm Wmin3 lower limit of the equivalent width range (for a3 and b3) 107 A1 --- --- [-] 108-110 I3 0.1pm Wmax3 upper limit of the equivalent width range (for a3 and b3)
Byte-by-byte Description of file: table5.dat
Bytes Format Units Label Explanations
1- 8 A8 --- Ref Published data reference code (1) 10- 14 F5.2 --- [Fe/H] Adopted [Fe/H] value 17- 21 F5.2 --- [O/Fe]77 O I 7771, 7774, 7775Å mean non-LTE result of [O/Fe] 23- 27 F5.2 --- <Del>77 O I 7771, 7774, 7775Å mean non-LTE correction 29- 34 F6.2 --- [O/Fe]63 The [O I] 6300/6363Å mean result of [O/Fe] 36- 40 F5.2 --- <Del>63 The [O I] 6300/6363Å non-LTE correction (zero assumed) 41- 46 F6.0 K Teff Adopted effective temperature 47- 52 F6.2 cm/s2 logg Adopted logarithmic surface gravity 54- 56 F3.1 km/s xi Adopted microturbulence 58- 69 A12 --- Star Name of the star 70- 74 F5.1 0.1pm EW7771 O I 7771.94 line adopted equivalent width 76- 80 F5.2 --- ALTE7771 O I 7771.94 line LTE derived abundance (G1) 82- 86 F5.2 --- Del7771 ?=-9.99 O I 7771.94 line non-LTE correction (G1) 88- 92 F5.2 --- ANLTE7771 ?=-9.99 O I 7771.94 line resulting NLTE abundance (G1) 94- 99 F6.1 0.1pm EW7774 O I 7774.17 line adopted equivalent width 101-105 F5.2 --- ALTE7774 O I 7774.17 line LTE derived abundance (G1) 107-111 F5.2 --- Del7774 ?=-9.99 O I 7774.17 line non-LTE correction (G1) 113-117 F5.2 --- ANLTE7774 ?=-9.99 O I 7774.17 line resulting NLTE abundance (G1) 119-124 F6.1 0.1pm EW7775 O I 7775.39 line adopted equivalent width 126-130 F5.2 --- ALTE7775 O I 7775.39 line LTE derived abundance (G1) 132-136 F5.2 --- Del7775 ?=-9.99 O I 7775.39 line non-LTE correction (G1) 138-142 F5.2 --- ANLTE7775 ?=-9.99 O I 7775.39 line resulting NLTE abundance (G1) 144-149 F6.1 0.1pm EW6300 The [O I] 6300.30 line adopted equivalent width 151-155 F5.2 --- ALTE6300 The [O I] 6300.30 line LTE derived abundance (G1) 157-161 F5.2 --- Del6300 ?=-9.99 [O I] 6300.30 line non-LTE correction (0 assumed) (G1) (2) 163-167 F5.2 --- ANLTE6300 ?=-9.99 [O I] 6300.30 line final abundance (G1) 169-174 F6.1 0.1pm EW6363 The [O I] 6363.78 line adopted equivalent width 176-180 F5.2 --- ALTE6363 The [O I] 6363.78 line LTE derived abundance (G1) 182-186 F5.2 --- Del6363 ?=-9.99 [O I] 6363.78 line non-LTE correction (0 assumed) (G1) (2) 188-192 F5.2 --- ANLTE6363 ?=-9.99 [O I] 6363.78 line final abundance (G1)
Note (1): References for reanalysis data: ar : Abia & Rebolo (1989ApJ...347..186A) barb : Barbuy (1988A&A...191..121B) bem : Barbuy & Erdelyi-Mendez (1989A&A...214..239B) bk : Boesgaard & King (1993AJ....106.2309B) carretta : Carretta et al. (2000, Cat. J/A+A/356/238) cavallo : Cavallo et al. (1997PASP..109..226C) edvard : Edvardsson et al. (1993, Cat. J/A+A/275/101 and 1993, Cat. J/A+AS/102/603) king : King (1994ApJ...436..331K) kslp : Kraft et al. (1992AJ....104..645K) mishen : Mishenina et al. (2000A&A...353..978M) nissen : Nissen et al. (2002, Cat. J/A+A/390/235) skpl : Sneden et al. (1991AJ....102.2001S) slw : Sneden et al. (1979ApJ...234..964S) takeda : Takeda (See Takada-Hidai et al., 2001NewAR..45..549T) tlls : Tomkin et al. (1992AJ....104.1568T) Note (2): Note that NLTE correction for [O I] forbidden lines was assumed to be zero following the consequence of Sect. 4.2.
Global notes: Note (G1): logN(O) on the customary scale in which logN(H)=12
Acknowledgements: Yoichi Takeda
(End) Patricia Bauer [CDS] 20-Feb-2003
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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