The Effelsberg-Bonn H i Survey: Milky Way gas - First data release
The Effelsberg-Bonn H i Survey: Milky Way gas - First data release
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DOI：
10.1051/0004-6361/201527007
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发表时间：
2015-12
影响因子：
6.5
通讯作者：
B. Winkel;J. Kerp;L. Flöer;P. Kalberla;N. B. Bekhti;R. Keller;D. Lenz
中科院分区：
文献类型：
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作者：
B. Winkel;J. Kerp;L. Flöer;P. Kalberla;N. B. Bekhti;R. Keller;D. Lenz
语境。埃菲尔斯贝格-波恩 H i 巡天 (EBHIS) 是一项新的 21 厘米巡天，使用埃菲尔斯贝格的 100 米望远镜进行。它覆盖了整个北方天空，红移为 z ∼ 0.07，包括来自银河系和本地体积的 H i 线发射。目标。我们的目标是用第一个 EBHIS 数据发布*替代莱顿/阿根廷/波恩银河系 H i 调查 (LAB) 的北半球部分*，该数据显示了银河系中的 H i 气体。方法。七波束 L 波段阵列的使用使得使用 100 米级望远镜在合理的观测时间内进行全天空观测成为可能。最先进的快速傅立叶变换光谱仪提供必要的数据读出速度、动态范围和光谱分辨率，以应用软件射频干扰缓解。 EBHIS 针对杂散辐射进行了校正，并采用频率相关的通量密度校准和复杂的基线去除技术来确保尽可能高的数据质量。结果。对所得数据产品的详细分析表明，EBHIS 不仅在灵敏度和角分辨率方面优于 LAB，而且与 LAB 的强度尺度非常匹配，使得 EBHIS 可以用作 LAB 的直接替代品。数据产品以多种形式向公众提供。最重要的是，我们在 HEALPix 表示中提供了正确网格化的银河系 H i 柱密度图。为了最大限度地发挥 EBHIS 数据的有用性，我们估计了 H i 柱密度和亮度温度分布的不确定性，并考虑了系统效应。
Context. The Effelsberg–Bonn H i Survey (EBHIS) is a new 21-cm survey performed with the 100-m telescope at Effelsberg. It covers the whole northern sky out to a redshift of z ∼ 0.07 and comprises H i line emission from the Milky Way and the Local Volume. Aims. We aim to substitute the northern-hemisphere part of the Leiden/Argentine/Bonn Milky Way H i survey (LAB) with this first EBHIS data release∗, which presents the H i gas in the Milky Way regime. Methods. The use of a seven-beam L-band array made it feasible to perform this all-sky survey with a 100-m class telescope in a reasonable amount of observing time. State-of-the-art fast-Fourier-transform spectrometers provide the necessary data read-out speed, dynamic range, and spectral resolution to apply software radio-frequency interference mitigation. EBHIS is corrected for stray radiation and employs frequency-dependent flux-density calibration and sophisticated baseline-removal techniques to ensure the highest possible data quality. Results. Detailed analyses of the resulting data products show that EBHIS is not only outperforming LAB in terms of sensitivity and angular resolution, but also matches the intensity-scale of LAB extremely well, allowing EBHIS to be used as a drop-in replacement for LAB. Data products are made available to the public in a variety of forms. Most important, we provide a properly gridded Milky Way H i column density map in HEALPix representation. To maximize the usefulness of EBHIS data, we estimate uncertainties in the H i column density and brightness temperature distributions, accounting for systematic effects.