C,N and key heavy elements in metal-poor and very metal-poor carbon-enhanced stars
نویسندگان
چکیده
منابع مشابه
Carbon-enhanced metal-poor stars and thermohaline mixing
One possible scenario for the formation of carbon-enhanced metal-poor stars is the accretion of carbon-rich material from a binary companion which may no longer visible. It is generally assumed that the accreted material remains on the surface of the star and does not mix with the interior until first dredge-up. However, thermohaline mixing should mix the accreted material with the original ste...
متن کاملSulphur abundance in very metal-poor stars
We have obtained high-resolution high signal-to-noise spectra of the S i nearinfrared doublet at 8694 Å in eight metal-poor stars with metallicities in the range −0.6 ≤[Fe/H]≤ −3.0. Elemental sulphur abundances were derived for six targets and upper limits were set for two of the most metal-poor stars in the sample. The sulphur doublet at 8694.62 Å has been detected in three stars (HD19445, HD2...
متن کاملAbundances in Very Metal-Poor Stars
Metal-poor stars provide information on the characteristics and chemical evolution of the halo population of the Galaxy, the first epoch of star formation and Galaxy formation (not just locally but with relevance to high-redshift objects), and big bang nucleosynthesis. This review looks at recent developments in this subject.
متن کاملBoron in Very Metal-Poor Stars
We have observed the B I λ 2497 Å line to derive the boron abundances of two very metal-poor stars selected to help in tracing the origin and evolution of this element in the early Galaxy: BD +23◦3130 and HD 84937. The observations were conducted using the Goddard High Resolution Spectrograph on board the Hubble Space Telescope. A very detailed abundance analysis via spectral synthesis has been...
متن کاملHeavy Element Diffusion in Metal Poor Stars
Stellar evolution models which include the effect of helium and heavy element diffusion have been calculated for initial iron abundances of [Fe/H] = −2.3, −2.1, −1.9 and −1.7. These models were calculated for a large variety of masses and three separate mixing lengths, α = 1.50, 1.75 and 2.00 (with α = 1.75 being the solar calibrated mixing length). The change in the surface iron abundance for ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Proceedings of the International Astronomical Union
سال: 2005
ISSN: 1743-9213,1743-9221
DOI: 10.1017/s1743921305005582