Detailed abundances in stars belonging to ultra-faint dwarf spheroidal galaxies
Detailed abundances in stars belonging to ultra-faint dwarf spheroidal galaxies
复制标题
属于超微弱矮球状星系的恒星的详细丰度
DOI：
--
复制
发表时间：
2012
期刊：
影响因子：
--
通讯作者：
L. Sbordone
中科院分区：
文献类型：
--
作者：
P. Francois;L. Monaco;S. Villanova;M. Catelán;P. Bonifacio;M. Bellazzini;C. M. Bidin;G. Marconi;Doug Geisler;L. Sbordone
我们报告了属于超微弱矮星系（以下简称UfDSphs）的贫金属恒星的详细化学成分的初步结果。由于安装在ESO VLT装置上的高效光谱仪X-Shooter获得了光谱，因此确定了丰度。超微弱的矮球状恒星样品的丰度比在相同金属丰度的现场晕星中测量的丰度略低。我们在大力神星中没有发现像科赫在他的两颗大力神星中发现的那样的极端丰度。中子捕获元素Ba和Sr的合成似乎起源于银河系演化早期的同一核合成过程。
We report preliminary results concerning the detailed chemical composition of metal poor stars belonging to close ultra-faint dwarf galaxies (hereafter UfDSphs). The abundances have been determined thanks to spectra obtained with X-Shooter, a high efficiency spectrograph installed on one of the ESO VLT units. The sample of ultra-faint dwarf spheroidal stars have abundance ratios slightly lower to what is measured in field halo star of the same metallicity. We did not find extreme abundances in our Hercules stars as the one found by Koch for his 2 Hercules stars. The synthesis of the neutron capture elements Ba and Sr seems to originate from the same nucleosynthetic process in operation during the early stages of the galactic evolution.