High Resolution Optical Spectroscopy of an Intriguing High-Latitude B-Type Star HD119608

ŞAHİN T.

ASTROPHYSICAL BULLETIN, cilt.73, sa.1, ss.35-51, 2018 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 73 Sayı: 1
  • Basım Tarihi: 2018
  • Doi Numarası: 10.1134/s1990341318010030
  • Dergi Adı: ASTROPHYSICAL BULLETIN
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.35-51
  • Anahtar Kelimeler: stars: magnetic field, stars: chemically peculiar, stars: individual: HD119608, HORIZONTAL-BRANCH STARS, GLOBULAR-CLUSTER M15, CHEMICAL ABUNDANCES, V-HYDRAE, INTERSTELLAR ABSORPTION, LINE IDENTIFICATION, GALACTIC LATITUDES, BROADENING TABLES, BETA PHOTOMETRY, NEUTRAL HELIUM
  • Akdeniz Üniversitesi Adresli: Evet

Özet

We present an LTE analysis of high resolution echelle optical spectra obtained with the 3.9-m Anglo-Australian Telescope (AAT) and the UCLES spectrograph for a B1Ib high galactic latitude supergiant HD119608. A fresh determination of the atmospheric parameters using line-blanketed LTE model atmospheres and spectral synthesis provided T (eff) = 23 300 +/- 1000 K, log g = 3.0 +/- 0.3, and the microturbulent velocity xi = 6.0 +/- 1.0 kms(-1) and [Fe/H] = 0.16. The rotational velocity of the star was derived fromC, O, N, Al, and Fe lines as v sin i = 55.8 +/- 1.3 kms(-1). Elemental abundances were obtained for 10 different species. He, Al, and P abundances of the star were determined for the first time. In the spectra, hot post-AGB status as well as the Pop I characteristics of the star were examined. The approximately solar carbon and oxygen abundances, along with mild excess in helium and nitrogen abundances do not stipulate a CNO processed surface composition, hence a hot post-AGB status. The LTE abundances analysis also indicates solar sulphur and moderately enriched magnesium abundances. The average abundances of B dwarfs of well studied OB associations and Population I stars show a striking resemblance to abundances obtained for HD119608 in this study. This may imply a runaway status for the star.

We present an LTE analysis of high resolution echelle optical spectra obtained with the 3.9-m Anglo-Australian Telescope (AAT) and the UCLES spectrograph for a B1Ib high galactic latitude supergiant HD119608. A fresh determination of the atmospheric parameters using line-blanketed LTE model atmospheres and spectral synthesis provided Teff = 23 300 ± 1000 K, log g = 3.0 ± 0.3, and the microturbulent velocity ξ = 6.0 ± 1.0 kms−1 and [Fe/H] = 0.16. The rotational velocity of the star was derived fromC, O, N, Al, and Fe lines as v sin i = 55.8 ± 1.3 kms−1. Elemental abundances were obtained for 10 different species. He, Al, and P abundances of the star were determined for the first time. In the spectra, hot post-AGB status as well as the Pop I characteristics of the star were examined. The approximately solar carbon and oxygen abundances, along with mild excess in helium and nitrogen abundances do not stipulate a CNO processed surface composition, hence a hot post-AGB status. The LTE abundances analysis also indicates solar sulphur and moderately enriched magnesium abundances. The average abundances of B dwarfs of well studiedOB associations and Population I stars show a striking resemblance to abundances obtained for HD119608 in this study. This may imply a runaway status for the star.