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arXiv · 2110.04298

The Hobby-Eberly Telescope Dark Energy Experiment (HETDEX) Survey Design, Reductions, and Detections

Karl Gebhardt·Erin Mentuch Cooper·Robin Ciardullo·Viviana Acquaviva·Ralf Bender·William P. Bowman·Barbara G. Castanheira·Gavin Dalton·Dustin Davis·Roelof S. de Jong·D. L. DePoy·Yaswant Devarakonda·Sun Dongsheng·Niv Drory·Maximilian Fabricius·Daniel J. Farrow·John Feldmeier·Steven L. Finkelstein·Cynthia S. Froning·Eric Gawiser·Caryl Gronwall·Laura Herold·Gary J. Hill·Ulrich Hopp·Lindsay R. House·Steven Janowiecki·Matthew Jarvis·Donghui Jeong·Shardha Jogee·Ryota Kakuma·Andreas Kelz·W. Kollatschny·Eiichiro Komatsu·Mirko Krumpe·Martin Landriau·Chenxu Liu·Maja Lujan Niemeyer·Phillip MacQueen·Jennifer Marshall·Ken Mawatari·Emily M. McLinden·Shiro Mukae·Gautam Nagaraj·Yoshiaki Ono·Masami Ouchi·Casey Papovich·Nao Sakai·Shun Saito·Donald P. Schneider·Andreas Schulze·Khavvia Shanmugasundararaj·Matthew Shetrone·Chris Sneden·Jan Snigula·Matthias Steinmetz·Benjamin P. Thomas·Brianna Thomas·Sarah Tuttle·Tanya Urrutia·Lutz Wisotzki·Isak Wold·Gregory Zeimann·Yechi Zhang
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Abstract

We describe the survey design, calibration, commissioning, and emission-line detection algorithms for the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX). The goal of HETDEX is to measure the redshifts of over a million Ly$\alpha$ emitting galaxies between 1.88<z<3.52, in a 540 deg^2 area encompassing a co-moving volume of 10.9 Gpc^3. No pre-selection of targets is involved; instead the HETDEX measurements are accomplished via a spectroscopic survey using a suite of wide-field integral field units distributed over the focal plane of the telescope. This survey measures the Hubble expansion parameter and angular diameter distance, with a final expected accuracy of better than 1%. We detail the project's observational strategy, reduction pipeline, source detection, and catalog generation, and present initial results for science verification in the COSMOS, Extended Groth Strip, and GOODS-N fields. We demonstrate that our data reach the required specifications in throughput, astrometric accuracy, flux limit, and object detection, with the end products being a catalog of emission-line sources, their object classifications, and flux-calibrated spectra.

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Karl Gebhardt, Erin Mentuch Cooper, Robin Ciardullo, Viviana Acquaviva, Ralf Bender, William P. Bowman, Barbara G. Castanheira, Gavin Dalton, Dustin Davis, Roelof S. de Jong, D. L. DePoy, Yaswant Devarakonda, Sun Dongsheng, Niv Drory, Maximilian Fabricius, Daniel J. Farrow, John Feldmeier, Steven L. Finkelstein, Cynthia S. Froning, Eric Gawiser, Caryl Gronwall, Laura Herold, Gary J. Hill, Ulrich Hopp, Lindsay R. House, Steven Janowiecki, Matthew Jarvis, Donghui Jeong, Shardha Jogee, Ryota Kakuma, Andreas Kelz, W. Kollatschny, Eiichiro Komatsu, Mirko Krumpe, Martin Landriau, Chenxu Liu, Maja Lujan Niemeyer, Phillip MacQueen, Jennifer Marshall, Ken Mawatari, Emily M. McLinden, Shiro Mukae, Gautam Nagaraj, Yoshiaki Ono, Masami Ouchi, Casey Papovich, Nao Sakai, Shun Saito, Donald P. Schneider, Andreas Schulze, Khavvia Shanmugasundararaj, Matthew Shetrone, Chris Sneden, Jan Snigula, Matthias Steinmetz, Benjamin P. Thomas, Brianna Thomas, Sarah Tuttle, Tanya Urrutia, Lutz Wisotzki, Isak Wold, Gregory Zeimann, Yechi Zhang. 2021-10-08. The Hobby-Eberly Telescope Dark Energy Experiment (HETDEX) Survey Design, Reductions, and Detections. https://doi.org/10.3847/1538-4357%2Fac2e03

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