Carbon isotope ratios and iron/hydrogen ratios in K giants
نویسندگان
چکیده
منابع مشابه
Patterns and controls of lotic algal stable carbon isotope ratios
Spatial and temporal variations in stable carbon isotope ratios (i.e., 813C) of primary producers are common but poorly understood features of isotopic characterizations of aquatic food webs. I investigated factors that control t13C of algae (concentration and 613C of inorganic carbon, algal fractionation, and growth rates) in riffle habitats across a gradient in stream size and productivity in...
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Using classical model atmospheres and an LTE analysis, Mg isotope ratios Mg:Mg:Mg are measured in 32 Hyades dwarfs covering 4000K ≤ Teff ≤ 5000K. We find no significant trend in any isotope ratio versus Teff and the mean isotope ratio is in excellent agreement with the solar value. We determine stellar parameters and Fe abundances for 56 Hyades dwarfs covering 4000K ≤ Teff ≤ 6200K. For stars wa...
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Introduction: High-precision measurements of Mg/Mg by multiple-collector inductively coupled plasma-source mass spectrometry (MC-ICPMS) have been used recently in our laboratory to constrain the thermal history of calcium aluminum-rich inclusions (CAIs) [1]. Presence of primary zoning profiles in at least some CAIs points to supersolidus and subsolidus diffusion as important factors in controll...
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ژورنال
عنوان ژورنال: Monthly Notices of the Royal Astronomical Society
سال: 1979
ISSN: 0035-8711,1365-2966
DOI: 10.1093/mnras/187.1.9p