Abundance analysis of the supergiant stars HD 80057 and HD 80404 based on their UVES Spectra

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Tanriverdi T., BAŞTÜRK Ö.

NEW ASTRONOMY, cilt.47, ss.46-56, 2016 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 47
  • Basım Tarihi: 2016
  • Doi Numarası: 10.1016/j.newast.2016.02.006
  • Dergi Adı: NEW ASTRONOMY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.46-56
  • Anahtar Kelimeler: Stars: abundances, Stars: individual: HD 80057, Stars: individual: HD 80404, Techniques: spectroscopic, ATOMIC TRANSITION-PROBABILITIES, EXPERIMENTAL OSCILLATOR-STRENGTHS, M-CIRCLE-DOT, SOLAR ABUNDANCE, QUANTITATIVE SPECTROSCOPY, RADIATIVE LIFETIMES, ULTRAVIOLET TRANSITIONS, CHEMICAL-COMPOSITION, MODEL ATMOSPHERES, HIPPARCOS STARS
  • Ankara Üniversitesi Adresli: Evet

Özet

This study presents elemental abundances of the early A-type supergiant HD 80057 and the late A type supergiant HD 80404. High resolution and high signal-to-noise ratio spectra published by the UVES Paranal Observatory Project (Bagnulo et al., 2003)(1) were analyzed to compute their elemental abundances using ATLAS9 (Kurucz, 1993; 2005; Sbordone et al., 2004). In our analysis we assumed local thermodynamic equilibrium. The atmospheric parameters of HD 80057 used in this study are from Firnstein and Przybilla (2012), and that of HD 80404 are derived from spectral energy distribution, ionization equilibria of Cr and Fe I/II, the fits to the wings of Balmer and Paschen lines as T-eff = 7700 +/- 150 K and log g = 1.60 +/- 0.15 (in cgs). The microturbulent velocities of HD 80057 and HD 80404 have been determined as 4.3 +/- 0.1 and 2.2 +/- 0.0 km s(-1), respectively. The rotational velocities are 15 +/- 1 and 7 +/- 2 km s(-1) and their macroturbulence velocities are 24 +/- 2 and 2 +/- 1 km s(-1). We have given the abundances of 25 ions of 19 elements for HD 80057 and 36 ions of 25 elements for HD 80404. The abundances are close to solar values, except for some elements (Na, Sc, Ti, V, Ba, and Sr). We have found the metallicities [M/H] for HD 80057 and HD 80404 as -0.16 +/- 0.24 and -0.04 +/- 0.16 dex, respectively. The evolutionary status of these stars are discussed and their nitrogen-to-carbon (N/C) and nitrogen-to oxygen (N/O) ratios show that they are in their blue supergiant phase before the red supergiant region. (C) 2016 Elsevier B.V. All rights reserved.