منابع مشابه
Carbon-enhanced Hyper-metal-poor Stars and the Stellar Imf at Low Metallicity
The two known “hyper-metal-poor” (HMP) stars, HE0107-5240 and HE1327-2326, have extremely high enhancements of the light elements C, N, and O relative to Fe and appear to represent a statistically significant excess population relative to the halo metallicity distribution extrapolated from [Fe/H] > −3. This study weighs the available evidence for and against three hypothetical origins for these...
متن کاملAbundances of UV bright stars in globular clusters
Two UV brights stars in globular clusters, ROA 5701 (ω Cen) and Barnard 29 (M 13) are analysed from highresolution UV and optical spectra. The main aim is the measurement of iron abundances from UV spectra obtained with the HST-GHRS. In addition atmospheric parameters and abundances for He, C, N, O, and Si are derived from optical spectra (ESO CASPEC) for ROA 5701 or taken from literature for B...
متن کاملC3tb20619j 5235..5240
Harvard-MIT Division of Health Sciences 76-453, Cambridge, MA 02139, USA. E-mail Department of Chemical Engineering, MIT, Department of Bio and Brain Engineering, Technology, Yuseong-gu, Daejeon 305-701, K Materials Science and Engineering Program Jolla, CA 92093, USA Department of Chemistry and Biochem Department of Nanoengineering, University 92093, USA Cancer Research Center, Sanford-Burnham...
متن کاملMid-UV Determination of Elliptical Galaxy Abundances and Ages
We investigate the effects of abundance and age on the mid-UV spectra and Mg2 strengths of stellar populations using simple population synthesis models. These models are used to constrain the star formation history of four nearby elliptical galaxies and spiral bulges. The mid-UV (1800 3200 Å) light of evolved stellar populations (> 1 Gyr) is dominated by the main sequence turn-off, unlike the o...
متن کاملOn the origin of HE 0107 - 5240 , the most iron deficient star presently known
We show that the ”puzzling” chemical composition observed in the extremely metal poor star HE0107-5240 may be naturally explained by the concurrent pollution of at least two supernovae. In the simplest possible model a supernova of quite low mass (∼ 15 M⊙), underwent a ”normal” explosion and ejected ∼ 0.06 M⊙ of Ni while a second one was massive enough (∼ 35 M⊙) to experience a strong fall back...
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/s1743921305005612