The chemical content of nearby galaxies from planetary nebulae: NGC 147
The chemical content of nearby galaxies from planetary nebulae: NGC 147
复制标题
行星状星云附近星系的化学成分：NGC 147
DOI：
10.1111/j.1365-2966.2006.11339.x
复制
发表时间：
2006
影响因子：
4.8
通讯作者：
Spain.
中科院分区：
文献类型：
--
作者：
D. Gonçalves;L. Magrini;P. Leisy;R. IaG;U. S. Paulo;Brazil Inaf;O. Arcetri;Italy Isaac Newton Group of Telescopes;S. I. A. D. Canarias;Spain.
我们报告了用双子星多目标摄谱仪对M31的伴星矮球状星系NGC 147中的8个行星状星云（PNe）的光谱观测结果。利用经验ICF方法和CLOUDY光电离模型推导了6种最亮PNe的物理化学性质。利用化学丰度之间的关系分析了低金属丰度环境中低质量和中质量恒星演化的不同方面。此外，还对ngc147的化学演化特征进行了研究。特别是，PNe的平均金属丰度O/H = 8.06 +0.09−0.12（对应于[Fe/H]PNe ~−0.97）接近老恒星群的金属丰度[Fe/H] =−1.0，这表明在相当长的时间内化学富集可以忽略不计。最后，讨论了本星系群矮星系的光度-金属丰度关系。dsph在光度-金属丰度图中的位置并不能排除它们是由古老的不规则矮星系（dIr）形成的，但它确实排除了它们是由现在的不规则矮星系形成的，因为它们的金属丰度之间的差异已经存在于它们更古老的星系群中。光度-金属丰度关系的偏移表明dsh的富集速度更快，并与不同的平均丰度比[O/Fe]一起证明了这两类星系不同的恒星形成历史。
We report the results of spectroscopic observations, obtained with the Gemini Multi-Object Spectrograph, of eight planetary nebulae (PNe) in the dwarf spheroidal (dSph) galaxy NGC 147, a companion of M31. The physico-chemical properties of the six brightest PNe were derived using both the empirical ICF method and photoionization modelling with CLOUDY. Different aspects of the evolution of low- and intermediate-mass stars in a low-metallicity environment are analysed using relationships between chemical abundances. In addition, certain features of the chemical evolution of NGC 147 were examined. In particular, the mean metallicity of PNe, O/H = 8.06 +0.09 −0.12 (corresponding to [Fe/H]PNe ∼− 0.97), is close to the metallicity of the old stellar population, [Fe/H] =− 1.0, suggesting a negligible chemical enrichment during a substantial amount of time. Finally, the luminosity‐metallicity relationship for the dwarf galaxies of the Local Group is discussed. The location in the luminosity‐metallicity diagram of dSphs does not exclude their formation from old dwarf irregular (dIr) galaxies, but it does exclude their formation from the present time dIrs, since the differences between their metallicities are already present in their older populations. The offset in the luminosity‐ metallicity relationship indicates a faster enrichment of dSphs and, together with the different average abundance ratio [O/Fe ]demonstrates the different star formation histories for these two types of galaxies.