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arXiv 2301.01799astro-ph.GAastro-ph.CO
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HETDEX Survey:发射线探索与源分类

The HETDEX Survey: Emission Line Exploration and Source Classification

Dustin Davis, Karl Gebhardt, Erin Mentuch Cooper, Robin Ciardullo, Maximilian Fabricius, Daniel J. Farrow, John J. Feldmeier, Steven L. Finkelstein, Eric Gawise… 展开作者

Dustin Davis, Karl Gebhardt, Erin Mentuch Cooper, Robin Ciardullo, Maximilian Fabricius, Daniel J. Farrow, John J. Feldmeier, Steven L. Finkelstein, Eric Gawiser, Caryl Gronwall, Gary J. Hill, Ulrich Hopp, Lindsay R. House, Donghui Jeong, Wolfram Kollatschny, Eiichiro Komatsu, Martin Landriau, Chenxu Liu, Shun Saito, Sarah Tuttle, Isak G. B. Wold, Gregory R. Zeimann, Yechi Zhang

AI总结:

本文介绍了 HETDEX 巡天及其主要分类工具 ELiXer,通过结合多种选择标准,在低分辨率下实现了 LAE 星系与低红移 [OII] 星系的高精度分离,满足 HETDEX 科学需求。

摘要:

The Hobby-Eberly Telescope Dark Energy Experiment (HETDEX) 是一项无目标光谱巡天,旨在以 1% 的精度测量 $z \sim 2.4$ 处的宇宙膨胀率(包括 $H(z)$ 和 $D_A(z)$)。HETDEX 正在测绘超过一百万个 Lyman Alpha 发射(LAE)星系及相似数量的低红移星系,作为大尺度结构的示踪物。测量的成功取决于观测后能否将具有 Ly$α$ 发射的星系与低红移(主要是 [OII])混入星系分离,且具有低污染率和高恢复率。The Emission Line eXplorer (ELiXer) 是 HETDEX 的主要分类工具,可根据科学需求在污染率与完整性之间提供可调的平衡。通过结合多种选择标准,ELiXer 改进了通常用于区分 LAE 与低红移 [OII] 发射星系的 20 Angstrom 静止系等值宽度截断。尽管光谱分辨率为 R $\sim800$,无法分辨 [OII] 双线,我们证明了以 98.1% 的准确率区分 LAE 与前景星系的能力。使用默认 ELiXer 配置,我们估计 Ly$α$ 被 [OII] 污染率为 1.2%,Ly$α$ 恢复率为 99.1%。这些比率满足 HETDEX 的科学要求。

英文摘要:

The Hobby-Eberly Telescope Dark Energy Experiment (HETDEX) is an untargeted spectroscopic survey that aims to measure the expansion rate of the Universe at $z \sim 2.4$ to 1% precision for both $H(z)$ and $D_A(z)$. HETDEX is in the process of mapping in excess of one million Lyman Alpha emitting (LAE) galaxies and a similar number of lower-z galaxies as a tracer of the large-scale structure. The success of the measurement is predicated on the post-observation separation of galaxies with Ly$α$ emission from the lower-$z$ interloping galaxies, primarily [OII], with low contamination and high recovery rates. The Emission Line eXplorer (ELiXer) is the principal classification tool for HETDEX, providing a tunable balance between contamination and completeness as dictated by science needs. By combining multiple selection criteria, ELiXer improves upon the 20 Angstrom rest-frame equivalent width cut commonly used to distinguish LAEs from lower-$z$ [OII] emitting galaxies. Despite a spectral resolving power, R $\sim800$, that cannot resolve the [OII] doublet, we demonstrate the ability to distinguish LAEs from foreground galaxies with 98.1% accuracy. We estimate a contamination rate of Ly$α$ by [OII] of 1.2% and a Ly$α$ recovery rate of 99.1% using the default ELiXer configuration. These rates meet the HETDEX science requirements.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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