标题： 蓝 Compact 星系的光谱研究 V. 氧丰度和金属丰度-亮度关系 显示英文标题

标题： Spectroscopic study of blue compact galaxies V. oxygen abundance and the metallicity-luminosity relation

摘要： 这是研究一个蓝 Compact 星系（BCG）样本的恒星组成、恒星形成历史、恒星形成率和金属丰度系列论文的第五篇。基于我们高质量的地基光谱观测，我们利用不同的氧丰度指示剂确定了样本中72个恒星形成BCG的电子温度、电子密度、氮丰度和氧丰度。氧丰度范围为7.15 < 12 + log (O/H) < 9.0，并发现氮在12 + log (O/H) > 8.2时主要为二级核合成产物，在12 + log (O/H) < 8.2时显然为一级核合成产物。为了评估不同氧丰度指示剂可能存在的系统差异，我们比较了用Te法、R23法、P法、N2法和O3N2法获得的BCG氧丰度。Te法推导出的氧丰度比强线经验丰度指示剂推导出的低0.1-0.25 dex，与基于区域样本的先前研究一致。我们确认了在大量丰度和亮度范围内BCG中的金属丰度-亮度关系的存在。我们的星系样本显示明亮星系的金属丰度-亮度关系的斜率（~ -0.05）比矮星系的稍浅（~ -0.17）。在本地星系和中间红移星系的金属丰度-亮度关系之间发现了偏移。这表明高红移发射线星系的金属丰度-亮度关系向较低丰度、较高亮度或两者都偏移。 显示英文摘要

摘要： This is the fifth paper in a series studying the stellar components, star formation histories, star formation rates and metallicities of a blue compact galaxy (BCG) sample. Based on our high-quality ground-based spectroscopic observations, we have determined the electron temperatures, electron densities, nitrogen abundances and oxygen abundances for 72 star-forming BCGs in our sample, using different oxygen abundance indicators. The oxygen abundance covers the range 7.15 < 12 + log (O/H)< 9.0, and nitrogen is found to be mostly a product of secondary nucleosynthesis for 12 + log (O/H)>8.2 and apparently a product of primary nucleosynthesis for 12 + log (O/H)< 8.2. To assess the possible systematic differences among different oxygen abundance indicators, we have compared oxygen abundances of BCGs obtained with the Te method, R23 method, P method, N2 method and O3N2 method. The oxygen abundances derived from the Te method are systematically lower by 0.1-0.25 dex than those derived from the strong line empirical abundance indicators, consistent with previous studies based on region samples. We confirm the existence of the metallicity-luminosity relation in BCGs over a large range of abundances and luminosities. Our sample of galaxies shows that the slope of the metallicity-luminosity relation for the luminous galaxies (~-0.05) is slightly shallower than that for the dwarf galaxies (~-0.17). An offset was found in the metallicity-luminosity relation of the local galaxies and that of the intermediate redshift galaxies. It shows that the metallicity-luminosity relation for the emission line galaxies at high redshift is displaced to lower abundances, higher luminosities, or both.