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Intensity mapping from the sky: synergizing the joint potential of [OIII] and [CII] surveys at reionization

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 نشر من قبل Hamsa Padmanabhan
 تاريخ النشر 2021
  مجال البحث فيزياء
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We forecast the ability of future-generation experiments to detect the fine-structure lines of the carbon and oxygen ions, [CII] and [OIII] in intensity mapping (IM) from the Epoch of Reionization ($z sim 6-8$). Combining the latest empirically derived constraints relating the luminosity of the [OIII] line to the ambient star-formation rate, and using them in conjunction with previously derived estimates for the abundance of [CII] in haloes, we predict the expected auto-correlation IM signal to be observed using next-generation facilities based on the Fred Young Submillimetre Telescope (FYST) and the balloon-borne facility, Experiment for Cryogenic Large-Aperture Intensity Mapping (EXCLAIM) over $z sim 5.3 - 7$. We describe how improvements to both the ground-based and balloon-based surveys in the future will enable a cross-correlation signal to be detected at $sim$ 10-40 $sigma$ over $z sim 5.3 - 7$. Finally, we propose a space-based mission targeting the [OIII] 88 and 52 $mu$m lines along with the [CII] 158 $mu$m line, configured to enhance the signal-to-noise ratio of cross-correlation measurements. We find that such a configuration can achieve a high-significance detection (hundreds to thousands of $sigma$) in both auto- and cross-correlation modes.

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