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Abundance Analysis of the Early Type Members of the Open Cluster M6. Tolgahan KILIÇOĞLU Ankara University, Department of Astronomy and Space Sciences, Ankara, Turkey Richard MONIER Lagrange Laboratory, Nice University, Nice, France LESIA Observatoire de Paris - Meudon, Meudon Luca FOSSATI
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Abundance Analysis of the Early Type Members of the Open Cluster M6 Tolgahan KILIÇOĞLU Ankara University, Department of Astronomy and Space Sciences, Ankara, Turkey Richard MONIER Lagrange Laboratory, Nice University, Nice, France LESIA Observatoire de Paris-Meudon, Meudon Luca FOSSATI Argelander-Institute for Astronomy, Bonn University, Germany Putting A Stars into Context: Evolution, Environment, and Related Stars, June 3-7, 2013, Moscow M.V. Lomonosov State University, Moscow, RUSSIA
The Open Cluster M6 Putting A Stars into Context: Evolution, Environment, and Related Stars, June 3-7, 2013, Moscow M.V. Lomonosov State University, Moscow, RUSSIA
The Open Cluster M6 • Age: 100 30 milion years • Distance: 500 pc • Reddening: • Johnson UBV [E(B-V)] : 0.15 0.01 (Strobel 1992, Paunzen 2006, Ahumada & Lapaset 2007) • Geneva 7color [E(b-y)] : 0.13 0.01 (Nicolet 1981, North & Cramer 1981) • Strömgren uvby [E(B2-V1)] : 0.11 0.01 (Schnenider 1985) • 209 members are identified. NOAO, NASA Rohlfs et al. (1959) Antalova (1972) Putting A Stars into Context: Evolution, Environment, and Related Stars, June 3-7, 2013, Moscow M.V. Lomonosov State University, Moscow, RUSSIA
Observations • VLT Telescopes • Flames/Giraffe Spectrograph • L479.7 • R=7800, 4501 – 5078 Å, = 577 • H525.8B • R=25900, 5143 – 5356 Å, = 213 • H572.8 • R=24200, 5597 – 5840 Å, = 243 • 120 objects were observed three times. Putting A Stars into Context: Evolution, Environment, and Related Stars, June 3-7, 2013, Moscow M.V. Lomonosov State University, Moscow, RUSSIA
The Atmospheric Parameters • Strömgren Photometry • Not applicable. • Geneva 7color Photometry • Künzli et al. (1997)’s calibrations • CALIB code (North, P., priv. comm.) • Used for 42 members. • Hb lines • Excitation Equilibrium • Ionisation Equilibrium Putting A Stars into Context: Evolution, Environment, and Related Stars, June 3-7, 2013, Moscow M.V. Lomonosov State University, Moscow, RUSSIA
The Atmospheric Parameters • NGC 6405 94, 13000 500 K, 4.00 0.10 dex Normalized Flux Wavelength (Å) Putting A Stars into Context: Evolution, Environment, and Related Stars, June 3-7, 2013, Moscow M.V. Lomonosov State University, Moscow, RUSSIA
The Atmospheric Parameters • NGC 6405 47, 9400 200 K, 4.20 0.10 dex Normalized Flux Wavelength (Å) Putting A Stars into Context: Evolution, Environment, and Related Stars, June 3-7, 2013, Moscow M.V. Lomonosov State University, Moscow, RUSSIA
The Atmospheric Parameters • NGC 6405 47, 9400 K, 4.00 dex Normalized Flux Wavelength (Å) Putting A Stars into Context: Evolution, Environment, and Related Stars, June 3-7, 2013, Moscow M.V. Lomonosov State University, Moscow, RUSSIA
The Atmospheric Parameters • NGC 6405 47, 9200 K, 4.20 dex Normalized Flux Wavelength (Å) Putting A Stars into Context: Evolution, Environment, and Related Stars, June 3-7, 2013, Moscow M.V. Lomonosov State University, Moscow, RUSSIA
The Atmospheric Parameters • NGC 6405 65, 6700 100 K, 4.20 0.20 dex Normalized Flux Wavelength (Å) Putting A Stars into Context: Evolution, Environment, and Related Stars, June 3-7, 2013, Moscow M.V. Lomonosov State University, Moscow, RUSSIA
Model Atmospheres • ATLAS9 Model Atmospheres (Kurucz 1993, Sbordone et al. 2004, Sbordone 2005) • Teff range: 5900 K – 16000 K • Log g range: 3.50 – 4.40 dex • Smalley (2004)’s prescriptions: • For Teff > 8500 K, = 0.00 • For 8500 K > Teff > 7000 K, = 0.50 • For 7000 K > Teff, = 1.25 Putting A Stars into Context: Evolution, Environment, and Related Stars, June 3-7, 2013, Moscow M.V. Lomonosov State University, Moscow, RUSSIA
The abundance analysis • SYNSPEC48 (Hubeny & Lanz 1992) • SYNPLOT (modified) • Calculating χ² for the observed and synthetic spectra • Linelist: gfhyperall.dat (Kurucz), Vald, Nist, ... • For B-type stars: He, (O), Si, (P), (S), Fe • For A-type stars: C, O, Mg, Si, Ca, Sc, Ti, Cr, Mn, Fe, Ni, Y, Ba • For F-type stars: C, Mg, Ca, Sc, Ti, Cr, Mn, Fe, Ni, Y, Ba Putting A Stars into Context: Evolution, Environment, and Related Stars, June 3-7, 2013, Moscow M.V. Lomonosov State University, Moscow, RUSSIA
The abundance analysis Putting A Stars into Context: Evolution, Environment, and Related Stars, June 3-7, 2013, Moscow M.V. Lomonosov State University, Moscow, RUSSIA
The abundance analysis • An Am star candidate: NGC 6405 47 (Kılıçoğlu, Monier & Fossati 2012) • Te = 9400 K • Log g = 4.20 • vsini = 5.1 km/s • vmic = 2.3 km/s Putting A Stars into Context: Evolution, Environment, and Related Stars, June 3-7, 2013, Moscow M.V. Lomonosov State University, Moscow, RUSSIA
The abundance analysis • A He weak PGa star candidate: NGC6405 20 (Kılıçoğlu, Monier & Fossati 2012) • Fundamental Parameters • Te = 15400 500 K • logg = 4.00 0.2 dex • vsini = 31 3 km/s Putting A Stars into Context: Evolution, Environment, and Related Stars, June 3-7, 2013, Moscow M.V. Lomonosov State University, Moscow, RUSSIA
The abundance analysis • Double/Multiple Stars: NGC 6405 99 Putting A Stars into Context: Evolution, Environment, and Related Stars, June 3-7, 2013, Moscow M.V. Lomonosov State University, Moscow, RUSSIA
Results / Discussions A-type stars F-type stars [X/H] Errors: Mg, Si, Fe, Ti ~ 0.2 dex C, O, Ca, Sc ~ 0.3 dex Y, Ba ~ 0.4 – 0.6 dex [X/H] Putting A Stars into Context: Evolution, Environment, and Related Stars, June 3-7, 2013, Moscow M.V. Lomonosov State University, Moscow, RUSSIA
Discussion Effective temperature vs. iron abundance vsini vs. iron abundance Putting A Stars into Context: Evolution, Environment, and Related Stars, June 3-7, 2013, Moscow M.V. Lomonosov State University, Moscow, RUSSIA
Discussions • Elemental stratification in A-type stars? • The competition between radiative diffusion and mixing mechanisms (rotation, turbulence, meridional mixing, ...) Gebran & Monier (2008) Putting A Stars into Context: Evolution, Environment, and Related Stars, June 3-7, 2013, Moscow M.V. Lomonosov State University, Moscow, RUSSIA
Discussions • Elemental stratification in A-type stars? • The competition between radiative diffusion and mixing mechanisms (rotation, turbulence, meridional mixing, ...) • To do list • Evolution models to understand the chemical evolution • Turcotte et al. (1998, F stars) • Richer et al. (2000, A stars) Gebran & Monier (2008) Putting A Stars into Context: Evolution, Environment, and Related Stars, June 3-7, 2013, Moscow M.V. Lomonosov State University, Moscow, RUSSIA
Discussions • Elemental stratification in A-type stars? • The competition between radiative diffusion and mixing mechanisms (rotation, turbulence, meridional mixing, ...) • To do list • Evolution models to understand the chemical evolution • Turcotte et al. (1998, F stars) • Richer et al. (2000, A stars) Gebran & Monier (2008) Putting A Stars into Context: Evolution, Environment, and Related Stars, June 3-7, 2013, Moscow M.V. Lomonosov State University, Moscow, RUSSIA
References • Rohlfs, K., Schrick, K. W., Stock, J. 1959, “Lichtelektrische Dreifarben-Photometrie von NGC6405 (M6). Mit 3 Textabbildungen”, Zeitschrift für Astrophysik, 47, 15. • Schneider H. 1985. Stromgren photometry of open clusters. I - NGC 6281, NGC 6405.Astronomy and Astrophysics Supplement Series. 61, 45-51. • Antalová, A. 1972. UBV photographic photometry of stars in the region AR1950: 17h03m -17h41m, Decl1950: -28.8° to -33.4°. III. The catalogue and identification maps ofopen star clusters: NGC 6405, NGC 6383, "NGC 6374", AV 2, NGC 6416 and Hemissions region: GUM 67(Av 3), GUM 68 (Av 2). Bulletin of the AstronomicalInstitute of Czechoslovakia, 23, 126. • Strobel, A.; Skaba, W.; Proga, D. 1992. Estimation of the ages and distances of open clustersfrom the Palomar Observatory Sky Survey. Astronomy and AstrophysicsSupplement Series, 93, 271-291. • Paunzen, E.; Netopil, M.; Iliev, I. Kh.; Maitzen, H. M.; Claret, A.; Pintado, O. I. 2006. CCD photometric search for peculiar stars in open clusters. VII. Berkeley 11, Berkeley 94, Haffner 15, Lyngå 1, NGC 6031, NGC 6405, NGC 6834 and Ruprecht 130. Astronomy and Astrophysics, 454, 171-178. • Ahumada, J., Lapasset, E. 2007. New Catalogue of blue stragglers in open clusters.Astronomy and Astrophysics, 463, 789-797. • Nicolet, B.1981. Geneva photometric boxes. III - Distances and reddenings for 43 openclusters. Astronomy and Astrophysics, 104, 185-197. • North, P.; Cramer, N. 1981. Ap stars detected in open clusters by the Geneva photometry.International Conference on Astrophysics, 23rd, Liege, Belgium, June 23-26, 1981,Reports. s. 55-59. • Künzli, M.; North, P.; Kurucz, R. L.; Nicolet, B. 1997. A calibration of Geneva photometryfor B to G stars in terms of Teff, log G and [M/H]. A & A Supplement series, 122,51-77. • Kurucz, R. L. 1993, CD-ROM 13, ATLAS9 Stellar Atmosphere Programs and 2 km/s Grid (Cambridge: Smithsonian Astrophys. Obs.). • Sbordone, L., Bonifacio, P., Castelli, F., & Kurucz, R. L. 2004, Memorie della Societa Astronomica Italiana Supplement, 5, 93 • Sbordone, L., 2005, Memorie della Societa Astronomica Italiana Supplement, 8, 61 • Smalley, B. 2004, “Observations of convection in A-type stars”, IAU Symp., 224, 131. • Hubeny, I., Lanz, T., 1992, Accelerated complete-linearization method for calculating NLTE modelstellar atmospheres, A&A, 262,501. • Kılıçoğlu T., Monier R., Fossati, L. 2012, “Abundance analysis of B, A and F dwarfs in the M6 open cluster: Spectrum synthesis method”, SF2A-2012, 351. • Kılıçoğlu T., Monier R., Fossati, L. 2012, “Detection of a new phosphorus rich star in the open cluster M6”, SF2A-2012, 355. • Gebran, M., Monier, R.,2008, Chemical composition of A and F dwarfs members of the Pleiadesopen cluster, A&A, 483,567. • Turcotte, S., Richer, J., Michaud, G., 1998. Consistent Evolution of F Stars: Diffusion, Radiative Accelerations, and Abundance Anomalies, ApJ., 504, 559. • Richer, J., Michaud, G., Turcotte, S.,2000, “The Evolution of AMFM Stars, Abundance Anomalies,and Turbulent Transport”, ApJ., 529, 338. Putting A Stars into Context: Evolution, Environment, and Related Stars, June 3-7, 2013, Moscow M.V. Lomonosov State University, Moscow, RUSSIA