A MOLECULAR LINE SCAN IN THE HUBBLE DEEP FIELD NORTH
A MOLECULAR LINE SCAN IN THE HUBBLE DEEP FIELD NORTH
复制标题
哈勃北部深空域的分子线扫描
DOI：
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发表时间：
2013
期刊：
影响因子：
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通讯作者：
A. Weiss
中科院分区：
文献类型：
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作者：
R. Decarli;F. Walter;C. Carilli;D. Riechers;P. Cox;R. Neri;M. Aravena;E. Bell;F. Bertoldi;D. Colombo;E. da Cunha;E. Daddi;M. Dickinson;D. Downes;R. Ellis;L. Lentati;R. Maiolino;K. Menten;H. Rix;M. Sargent;D. Stark;B. Weiner;A. Weiss
我们提出了一个分子线扫描在哈勃深场北（HDF-N），覆盖整个3毫米窗口（79-115 GHz）使用IRAM高原德布尔干涉仪。我们的CO红移覆盖范围包括z = 0.45，1 π z = 1.9和所有z = 2。我们达到了CO检测限，其深度足以检测到迄今为止文献中报道的基本上所有z > 1的CO线。我们已经开发和应用不同的线搜索算法，导致在17行候选人的发现。我们估计，假阳性线检测的比率为10.2/17。我们从HDF-N的深层辅助数据库中识别出其中七个候选者的光学/近红外对应物，并研究其可用的光谱能量分布。在我们的扫描中，两个安全的CO检测被确定为z = 1.784和z = 2.047的恒星形成星系。这些星系的颜色与“BzK”颜色选择一致，与类似尘埃连续光度的星系相比，它们显示出相对明亮的CO发射。我们还检测到两个光谱线在亚毫米星系HDF 850.1在z = 5.183。我们认为额外的九行候选人是高质量的。我们的观测还提供了一个深3 mm的连续谱图（1σ噪声水平= 8.6 μJy束-1）。通过叠加的方法，我们发现，光学/MIR明亮的星系只贡献<50%的星星形成率密度在1 < z < 3，除非高尘埃温度调用。目前的研究代表了第一个，基本的一步，在“正常”的星系在高Z，在阿尔马时代的河外天文学的一个重要目标的分子气体的无偏见的普查。
We present a molecular line scan in the Hubble Deep Field North (HDF-N) that covers the entire 3 mm window (79–115 GHz) using the IRAM Plateau de Bure Interferometer. Our CO redshift coverage spans z ≲ 0.45, 1 ≲ z ≲ 1.9 and all z ≳ 2. We reach a CO detection limit that is deep enough to detect essentially all z > 1 CO lines reported in the literature so far. We have developed and applied different line-searching algorithms, resulting in the discovery of 17 line candidates. We estimate that the rate of false positive line detections is ∼2/17. We identify optical/NIR counterparts from the deep ancillary database of the HDF-N for seven of these candidates and investigate their available spectral energy distributions. Two secure CO detections in our scan are identified with star-forming galaxies at z = 1.784 and at z = 2.047. These galaxies have colors consistent with the “BzK” color selection and they show relatively bright CO emission compared with galaxies of similar dust continuum luminosity. We also detect two spectral lines in the submillimeter galaxy HDF 850.1 at z = 5.183. We consider an additional nine line candidates as high quality. Our observations also provide a deep 3 mm continuum map (1σ noise level = 8.6 μJy beam−1). Via a stacking approach, we find that optical/MIR bright galaxies contribute only to <50% of the star formation rate density at 1 < z < 3, unless high dust temperatures are invoked. The present study represents a first, fundamental step toward an unbiased census of molecular gas in “normal” galaxies at high-z, a crucial goal of extragalactic astronomy in the ALMA era.