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J/A+A/607/A135 NGC 104, 6121 & 6809 AGB and RGB stars Na abundance (Wang+, 2017)

Sodium abundances of AGB and RGB stars in Galactic globular clusters II. Analysis and results of NGC 104, NGC 6121, and NGC 6809. Wang Y., Primas F., Charbonnel C., Van der Swaelmen M., Bono G., Chantereau W., Zhao G. <Astron. Astrophys. 607, A135 (2017)> =2017A&A...607A.135W (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, globular ; Stars, giant ; Abundances ; Photometry ; Radial velocities Keywords: stars: abundances - globular clusters: general - globular clusters: individual: NGC 104 - globular clusters: individual: NGC 6121 - globular clusters: individual: NGC 6809 Abstract: We analyze high-resolution spectra of a large sample of asymptotic giant branch AGB and red giant branch (RGB) stars in the Galactic GCs NGC 104, NGC 6121, and NGC 6809 obtained with FLAMES/GIRAFFE at ESO/VLT, and determine their Na abundances. This is the first time that the AGB stars in NGC 6809 are targeted. We find that NGC 104 and NG 6809 have comparable AGB and RGB Na abundance distributions, while NGC 6121 shows a lack of very Na-rich AGB stars. Moreover, to investigate the dependence of AGB Na abundance dispersion on GC parameters, we compare the AGB [Na/H] distributions of a total of nine GCs, with five determined by ourselves with homogeneous method and four from literature, covering a wide range of GC parameters. Their Na abundances and multiple populations of AGB stars form complex picture. In some GCs, AGB stars have similar Na abundances and/or second-population fractions as their RGB counterparts, while some GCs do not have Na-rich second-population AGB stars, and various cases exist between the two extremes. In addition, the fitted relations between fractions of the AGB second population and GC global parameters show that the AGB second-population fraction slightly anticorrelates with GC central concentration, while no robust dependency can be confirmed with other GC parameters. Description: The spectra of our sample of AGB and RGB stars in the Galactic globular clusters NGC 104, NGC 6121 and NGC 6809 were obtained with the high-resolution multi-object spectrograph FLAMES, mounted on ESO/VLT-UT2, taking advantage of GIRAFFE for the majority of our sample stars and used the UVES fibres for the brightest objects of each cluster. The basic information of our sample stars are listed in Table 3, including the evolutionary phase, instrument used for observation, coordinates, photometry and barycentric radial velocity. Our Fe abundances were derived from the equivalent widths of Fe lines, while the Na abundances were determined with spectra synthesis. Both FeI and Na abundances have been corrected for the non-LTE effect. In Table 5 we show the derived stellar parameters of our sample stars, and the Na abundances are shown in Table 7. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table3.dat 176 282 Basic information of our sample stars table5.dat 101 282 Stellar parameters of our sample stars table7.dat 50 282 Na abundances of our sample stars
See also: J/A+A/592/A66 : NGC 2808 AGB and RGB stars Na abundance (Wang+, 2016) Byte-by-byte Description of file: table3.dat
Bytes Format Units Label Explanations
2- 5 A4 --- NGC Globular cluster identification 9- 17 A9 --- StarID Star identification (1) 22- 24 A3 --- EvolPh Evolutionary phase 27- 38 A12 --- Inst Instrument used to obtain the spectrum 43- 44 I2 h RAh Right Ascension J2000 (hours) 46- 47 I2 min RAm Right Ascension J2000 (minutes) 49- 53 F5.2 s RAs Right Ascension J2000 (seconds) 56 A1 --- DE- Declination J2000 (sign) 57- 58 I2 deg DEd Declination J2000 (degrees) 60- 61 I2 arcmin DEm Declination J2000 (minutes) 63- 67 F5.2 arcsec DEs Declination J2000 (seconds) 72- 77 F6.3 mag Bmag Apparent B magnitude (2) 80- 85 F6.4 mag e_Bmag Error of B magnitude (2) 89- 94 F6.3 mag Vmag Apparent V magnitude (2) 97-102 F6.4 mag e_Vmag Error of V magnitude (2) 106-111 F6.3 mag Imag Apparent I magnitude (2) 114-119 F6.4 mag e_Imag Error of I magnitude (2) 123-128 F6.3 mag Jmag ? J magnitude (3) 131-135 F5.3 mag e_Jmag ? Error of J magnitude (3) 139-144 F6.3 mag Hmag ? H magnitude (3) 147-151 F5.3 mag e_Hmag ? Error of H magnitude (3) 155-160 F6.3 mag Kmag ? K magnitude (3) 163-167 F5.3 mag e_Kmag ? Error of K magnitude (3) 171-176 F6.2 km/s RV Barycentric radial velocity
Note (1): The 'StarID' reports the original ID from the photometric catalogue, to which we added the suffix AGB/RGB to ease our own data handling. Note (2): The optical photometry (B, V and I) were obtained from the Johnson-Morgan photometric database which is part of the project described in Stetson (2000PASP..112..925S, 2005PASP..117.1325S). Note (3): The infrared J, H and K magnitudes were obtained from the 2MASS catalogue (Skrutskie et al., 2006, Cat. VII/233) by coordinates cross-matching.
Byte-by-byte Description of file: table5.dat
Bytes Format Units Label Explanations
2- 5 A4 --- NGC Globular cluster identification 9- 17 A9 --- StarID Star identification 21- 23 A3 --- EvolPh Evolutionary phase 28- 31 I4 K Teff Effective temperature 34- 38 F5.1 K s_Teff Scatter of the temperature (1) 44- 47 F4.2 --- logg Surface gravity 53- 56 F4.2 km/s Vturb Microturbulence velocity 61- 65 F5.2 [-] [FeI/H]LTE LTE [FeI/H] ratio 71- 74 F4.2 [-] s_FeIline Abundance dispersion of FeI lines 79- 83 F5.2 [-] [FeII/H] Line ratio [FeII/H] 89- 92 F4.2 [-] s_FeIIline Abundance dispersion of FeII lines 97-101 F5.2 [-] [FeI/H]NLTE NLTE [FeI/H] ratio
Note (1): The s_Teff (σTeff) is the scatter of the temperatures derived from the five colors we considered.
Byte-by-byte Description of file: table7.dat
Bytes Format Units Label Explanations
2- 5 A4 --- NGC Globular cluster identification 9- 17 A9 --- StarID Star identification 21- 23 A3 --- EvolPh Evolutionary phase 28- 32 F5.2 [-] [Na/H]LTE ? LTE [Na/H] (1) 37- 41 F5.2 [-] [Na/H]NLTE ? NLTE [Na/H] (1) 46- 50 F5.2 [-] [Na/FeI]NLTE ? NLTE [Na/FeI] (1)
Note (1): The abundance value is left blank for the stars whose Na line/lines are of poor quality or saturate, and no reliable abundance could be derived.
Acknowledgements: Yue Wang, ywang(at) References: Wang et al., Paper I 2016A&A...592A..66W, Cat. J/A+A/592/A66
(End) Yue Wang [NAOC, China], Patricia Vannier [CDS] 26-Sep-2017
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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