Spectroscopic follow-up of FIRBACK-South bright galaxies
Spectroscopic follow-up of FIRBACK-South bright galaxies
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FIRBACK-South 明亮星系的光谱跟踪
DOI：
10.1051/0004-6361:20031427
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发表时间：
2003
影响因子：
6.5
通讯作者：
H. Dole
中科院分区：
文献类型：
--
作者：
J. Patris;J. Patris;M. Dennefeld;M. Dennefeld;G. Lagache;H. Dole
我们对FIRBACK南马拉诺（FSM）场最亮的170 µm光源进行了光谱分析。光谱样品在4σ水平下完成90%。同时进行光谱分析并与微弱的IRAS（选择60 µm）参考样品的光谱进行比较。这两个样品中的源的特征是发射线光谱占优势，红外光度适中（10 10.5 < LIR < 10 12 L？）活动星系核的比例很低（约15%），大多数源都在附近（z < 0.3），尘埃，星星形成星系，中等星星形成率（每年几千万）。FSM星系的红外辐射显示出比预期更冷的光谱能量分布。两个样本中的星系（IRAS暗源和FSM）基本上与现有数据无法区分，似乎代表了一个人口近，冷，星星形成星系，而忽视了到现在。虽然它们对远红外背景的贡献似乎很低，但它们本身值得更详细的研究，以评估它们在局部宇宙化学演化中的重要性。当我们完成这170 µ ms巡天中较暗部分的后续工作时，我们将讨论较暗（可能是更遥远）的星系对远红外背景的贡献。
We have performed optical spectroscopy of the brightest 170 µm sources in the FIRBACK South Marano (FSM) field. The spectroscopic sample is 90% complete at the 4σ level. Analysis of spectra and comparison with spectra of a faint IRAS (60 µm selected) reference sample is conducted simultaneously. The sources in both samples are characterized by a predominance of emission-line spectra and moderate IR luminosities (10 10.5 < LIR < 10 12 L� )T he fraction of AGN's is low (about 15%) and the majority of sources are nearby (z < 0.3), dusty, star forming galaxies, with moderate star formation rates (a few 10 Mper year). The infrared emission of the FSM galaxies shows a colder spectral energy distribution than was expected. The galaxies in both samples (IRAS faint sources and FSM) are essentially undistinguishable with the available data, and seem to represent a population of closeby, cold, star forming galaxies rather neglected up to now. Although their contribution to the far-IR background seems to be low, they deserve a more detailed study on their own to assess their importance in the chemical evolution of the local universe. The contribution of fainter, presumably more distant, galaxies to the far-IR background will be discussed when we will have completed the follow-up of the fainter part of this 170 µ ms urvey.