The Chemical Composition Contrast between M3 and M13 Revisited: New Abundances for 28 Giant Stars in M3
نویسندگان
چکیده
منابع مشابه
Hst Uv Observations of the Cores of M3 and M13
We present preliminary results from HST/WFPC2 observations of the central regions of the of the Galactic globular clusters M13 & M3. The clusters are almost identical in most respects including chemical composition, but there are dramatic differences in both the horizontal branch (HB) and blue straggler (BSS) populations. The M13 HB has a long blue tail extending 4.5 mag in V, reaching well bel...
متن کاملThe Chemical Inhomogeneity of Faint M13 Stars: C and N Abundances
Building upon earlier observations which demonstrate substantial star-to-star differences in the carbon abundances of M13 subgiants, we present new Keck LRIS spectra reaching more that 1.5 mag below the M13 main-sequence turn-off (to V ≈ 20). Our analysis reveals a distribution of C abundances similar to that found among the subgiants, implying little change in the compositions of the M13 stars...
متن کاملChemical Abundances for Seven Giant Stars in M68 (ngc 4590) : a Globular Cluster with Abnormal Silicon and Titanium Abundances
We present a detailed chemical abundance study of seven giant stars in M68 including six red giants and one post-AGB star. We find significant differences in the gravities determined using photometry and those obtained from ionization balance, which suggests that non-LTE effects are important for these low-gravity, metal-poor stars. We adopt an iron abundance using photometric gravities and Fe ...
متن کاملAbundances in red giant stars of NGC 2808 and correlations between chemical anomalies and global parameters in globular clusters 1
We present the abundance analysis of stars from the tip of the red giant branch (RGB) to below the RGB-bump in the globular cluster NGC 2808, based on high resolution echelle spectra. We derived abundances of Al, α-process elements (Si I, Ca I, Ti I and Ti II) and Fe-group elements (Sc II, V I, Cr I, Cr II, Mn I, Co I, Ni I). Apart from Mg being somewhat reduced, likely because it has been depl...
متن کاملChemical Abundances and Yields from Massive Stars
Stellar rotation produces an internal mixing of the elements due to shear instability and meridional circulation. This leads to observable N/C enhancements in massive stars above about 7–9 M⊙. Rotation also favours mass loss by stellar winds. Mass loss effects dominate for masses above 30 M⊙, while mixing dominates below that limit. The effects of mixing are also much larger at lower metallicit...
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: The Astronomical Journal
سال: 2004
ISSN: 0004-6256,1538-3881
DOI: 10.1086/381907