论文标题
部分可观测时空混沌系统的无模型预测
Strong [OIII]λ5007 emission line compact galaxies in LAMOST DR9: Blueberries, Green Peas and Purple Grapes
论文作者
论文摘要
绿色的豌豆和蓝莓星系以其紧凑的尺寸,低质量,强烈的发射线和对高ZLYα发射星系的类似物而闻名。在这项研究中,从1547强[OIII]λ5007发射线紧凑的星系和1694光谱从lamost DR9中选择为0.0至0.59。根据红移分布,这些样品可以分为三组:蓝莓,绿豌豆和紫色葡萄。部署光学[MGII]λ2800线特征,BPT图,多波长SED拟合,miR颜色和miR变异性,以识别这些样品中的23个AGN候选者,这些样本被排除在以下SFR讨论中。我们使用Galex UV和Wise MiR数据执行多波长SED拟合。 Balmer减少的颜色过量表明,这些强[OIII]λ5007发射线紧凑的星系没有高度变红。星系的恒星质量是通过将lamost校准的光谱与发射线掩盖的。我们发现,随着红移的增加,SFR正在增加,而对于同一红移箱内的来源,SFR随质量而增加,质量与SFM相似。这些样品的中位金属性为12+log(O/h)为8.10。金属性随质量而增加,所有来源都低于质量金属关系。 [OIII]λ4363线的基于TE的直接TE金属性与基于经验N2的经验经验气相金属性一致。此外,这些紧凑的强[OIII]λ5007主要在密度较小的环境中。
Green Pea and Blueberry galaxies are well-known for their compact size, low mass, strong emission lines and analogs to high-z Lyα emitting galaxies. In this study, 1547 strong [OIII]λ5007 emission line compact galaxies with 1694 spectra are selected from LAMOST DR9 at the redshift range from 0.0 to 0.59. According to the redshift distribution, these samples can be separated into three groups: Blueberries, Green Peas and Purple Grapes. Optical [MgII]λ2800 line feature, BPT diagram, multi-wavelength SED fitting, MIR color, and MIR variability are deployed to identify 23 AGN candidates from these samples, which are excluded for the following SFR discussions. We perform the multi-wavelength SED fitting with GALEX UV and WISE MIR data. Color excess from Balmer decrement shows these strong [OIII]λ5007 emission line compact galaxies are not highly reddened. The stellar mass of the galaxies is obtained by fitting LAMOST calibrated spectra with the emission lines masked. We find that the SFR is increasing with the increase of redshift, while for the sources within the same redshift bin, the SFR increases with mass with a similar slope as the SFMS. These samples have a median metallicity of 12+log(O/H) of 8.10. The metallicity increases with mass, and all the sources are below the mass-metallicity relation. The direct-derived Te-based metallicity from the [OIII]λ4363 line agrees with the empirical N2-based empirical gas-phase metallicity. Moreover, these compact strong [OIII]λ5007 are mostly in a less dense environment.