Probing the intergalactic medium with Lyα and 21 cm fluctuations
We study 21 cm and Ly α fluctuations, as well as H α , while distinguishing between Ly α emission of galactic, diffuse, and scattered intergalactic medium (IGM) origin. Cross-correlation information about the state of the IGM is obtained, testing neutral versus ionized medium cases with different tr...
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| Main Authors: | , , |
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| Format: | Article (Journal) |
| Language: | English |
| Published: |
2017 October 11
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| In: |
The astrophysical journal
Year: 2017, Volume: 848, Issue: 1, Pages: 52 |
| ISSN: | 1538-4357 |
| DOI: | 10.3847/1538-4357/aa8eed |
| Online Access: | Verlag, kostenfrei, Volltext: http://dx.doi.org/10.3847/1538-4357/aa8eed Verlag, kostenfrei, Volltext: http://stacks.iop.org/0004-637X/848/i=1/a=52 
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| Author Notes: | Caroline Heneka, Asantha Cooray, and Chang Feng |
| Summary: | We study 21 cm and Ly α fluctuations, as well as H α , while distinguishing between Ly α emission of galactic, diffuse, and scattered intergalactic medium (IGM) origin. Cross-correlation information about the state of the IGM is obtained, testing neutral versus ionized medium cases with different tracers in a seminumerical simulation setup. In order to pave the way toward constraints on reionization history and modeling beyond power spectrum information, we explore parameter dependencies of the cross-power signal between 21 cm and Ly α , which displays a characteristic morphology and a turnover from negative to positive correlation at scales of a couple Mpc −1 . In a proof of concept for the extraction of further information on the state of the IGM using different tracers, we demonstrate the use of the 21 cm and H α cross-correlation signal to determine the relative strength of galactic and IGM emission in Ly α . We conclude by showing the detectability of the 21 cm and Ly α cross-correlation signal over more than one decade in scale at high signal-to-noise ratio for upcoming probes like SKA and the proposed all-sky intensity mapping satellites SPHEREx and CDIM, while also including the Ly α damping tail and 21 cm foreground avoidance in the modeling. |
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| Item Description: | Gesehen am 01.09.2020 |
| Physical Description: | Online Resource |
| ISSN: | 1538-4357 |
| DOI: | 10.3847/1538-4357/aa8eed |