Putting A Stars into Context: Evolution, Environment, and Related Stars, June 3-7, 2013, Moscow M.V. Lomonosov State University, Moscow, RUSSIA 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 IntroductionThe Open Cluster M6 ObservationWhich equipment? Deriving Atmospheric Parameters Photometric methods Spectral methods Abundance AnalysisMethods to derive abundances The results DiscussionStar-to-star abundance variations
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. Rohlfs et al. (1959) Antalova (1972) NOAO, NASA
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. H 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 NGC , 500 K, 4.00 0.10 dex The Atmospheric Parameters 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 NGC , 9400 200 K, 4.20 0.10 dex The Atmospheric Parameters Wavelength ( Å ) Normalized Flux
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 Wavelength ( Å ) Normalized Flux NGC , 9400 K, 4.00 dex
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 Wavelength ( Å ) Normalized Flux NGC , 9200 K, 4.20 dex
Putting A Stars into Context: Evolution, Environment, and Related Stars, June 3-7, 2013, Moscow M.V. Lomonosov State University, Moscow, RUSSIA NGC , 6700 100 K, 4.20 0.20 dex The Atmospheric Parameters Wavelength ( Å ) Normalized Flux
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) –T eff range: 5900 K – K –Log g range: 3.50 – 4.40 dex Smalley (2004)’s prescriptions: –For T eff > 8500 K, = 0.00 –For 8500 K > T eff > 7000 K, = 0.50 –For 7000 K > T eff, = 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 SYNSPEC48SYNSPEC48 (Hubeny & Lanz 1992) SYNPLOTSYNPLOT (modified) –Calculating χ² for the observed and synthetic spectra Linelist: gfhyperall.dat (Kurucz), Vald, Nist,... For B-type stars: He, (O), Si, (P), (S), FeFor B-type stars: He, (O), Si, (P), (S), Fe For A-type stars: C, O, Mg, Si, Ca, Sc, Ti, Cr,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,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 (Kılıçoğlu, Monier & Fossati 2012) –T e = 9400 K –Log g = 4.20 –vsini = 5.1 km/s –v mic = 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: NGC (Kılıçoğlu, Monier & Fossati 2012) Fundamental Parameters –T e = 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
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
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 1.Rohlfs, K., Schrick, K. W., Stock, J. 1959, “Lichtelektrische Dreifarben-Photometrie von NGC 6405 (M6). Mit 3 Textabbildungen”, Zeitschrift für Astrophysik, 47, Schneider H Stromgren photometry of open clusters. I - NGC 6281, NGC Astronomy and Astrophysics Supplement Series. 61, Antalová, A UBV photographic photometry of stars in the region AR1950: 17h03m - 17h41m, Decl1950: -28.8° to -33.4°. III. The catalogue and identification maps of open star clusters: NGC 6405, NGC 6383, "NGC 6374", AV 2, NGC 6416 and H emissions region: GUM 67(Av 3), GUM 68 (Av 2). Bulletin of the Astronomical Institute of Czechoslovakia, 23, Strobel, A.; Skaba, W.; Proga, D Estimation of the ages and distances of open clusters from the Palomar Observatory Sky Survey. Astronomy and Astrophysics Supplement Series, 93, Paunzen, E.; Netopil, M.; Iliev, I. Kh.; Maitzen, H. M.; Claret, A.; Pintado, O. I 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, Ahumada, J., Lapasset, E New Catalogue of blue stragglers in open clusters. Astronomy and Astrophysics, 463, Nicolet, B Geneva photometric boxes. III - Distances and reddenings for 43 open clusters. Astronomy and Astrophysics, 104, North, P.; Cramer, N Ap stars detected in open clusters by the Geneva photometry. International Conference on Astrophysics, 23rd, Liege, Belgium, June 23-26, 1981, Reports. s Künzli, M.; North, P.; Kurucz, R. L.; Nicolet, B A calibration of Geneva photometry for B to G stars in terms of Teff, log G and [M/H]. A & A Supplement series, 122, Kurucz, R. L. 1993, CD-ROM 13, ATLAS9 Stellar Atmosphere Programs and 2 km/s Grid (Cambridge: Smithsonian Astrophys. Obs.). 11.Sbordone, L., Bonifacio, P., Castelli, F., & Kurucz, R. L. 2004, Memorie della Societa Astronomica Italiana Supplement, 5, Sbordone, L., 2005, Memorie della Societa Astronomica Italiana Supplement, 8, Smalley, B. 2004, “Observations of convection in A-type stars”, IAU Symp., 224, Hubeny, I., Lanz, T., 1992, Accelerated complete-linearization method for calculating NLTE model stellar atmospheres, A&A, 262, 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, Kılıçoğlu T., Monier R., Fossati, L. 2012, “Detection of a new phosphorus rich star in the open cluster M6”, SF2A-2012, Gebran, M., Monier, R., 2008, Chemical composition of A and F dwarfs members of the Pleiades open cluster, A&A, 483, Turcotte, S., Richer, J., Michaud, G., Consistent Evolution of F Stars: Diffusion, Radiative Accelerations, and Abundance Anomalies, ApJ., 504, Richer, J., Michaud, G., Turcotte, S., 2000, “The Evolution of AMFM Stars, Abundance Anomalies, and Turbulent Transport”, ApJ., 529, 338.