Journal article

Deep multiredshift limits on Epoch of Reionization 21 cm power spectra from four seasons of Murchison Widefield Array observations

Cathryn M Trott, CH Jordan, S Midgley, N Barry, B Greig, B Pindor, JH Cook, G Sleap, SJ Tingay, D Ung, P Hancock, A Williams, J Bowman, R Byrne, A Chokshi, BJ Hazelton, K Hasegawa, D Jacobs, RC Joseph, W Li Show all



We compute the spherically averaged power spectrum from four seasons of data obtained for the Epoch of Reionization (EoR) project observed with the Murchison Widefield Array (MWA). We measure the EoR power spectrum over k = 0.07–3.0 h Mpc−1 at redshifts z = 6.5–8.7. The largest aggregation of 110 h on EoR0 high band (3340 observations), yields a lowest measurement of (43 mK)2 = 1.8 × 103 mK2 at k = 0.14 h Mpc−1 and z = 6.5 (2σ thermal noise plus sample variance). Using the Real-Time System to calibrate and the CHIPS pipeline to estimate power spectra, we select the best observations from the central five pointings within the 2013–2016 observing seasons, observing three independent fields and..

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Awarded by Australian Research Council Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D)

Awarded by ARC Future Fellowship


Awarded by Australian Research Council LIEF grant

Funding Acknowledgements

We thank the anonymous referee for the many comments that have clarified the methodology and improved the exposition. This research was supported by the Australian Research Council Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D), through project number CE170100013. CMT is supported by an ARC Future Fellowship under grant FT180100321. The International Centre for Radio Astronomy Research (ICRAR) is a Joint Venture of Curtin University and The University of Western Australia, funded by the Western Australian State government. KT is partially supported by JSPS KAKENHI Grant Numbers JP15H05896, JP16H05999, and JP17H01110, and Bilateral Joint Research Projects of JSPS. The MWA Phase II upgrade project was supported by Australian Research Council LIEF grant LE160100031 and the Dunlap Institute for Astronomy and Astrophysics at the University of Toronto. This scientific work makes use of the Murchison Radio-astronomy Observatory, operated by CSIRO. We acknowledge the Wajarri Yamatji people as the traditional owners of the Observatory site. Support for the operation of the MWA is provided by the Australian Government (NCRIS), under a contract to Curtin University administered by Astronomy Australia Limited. We acknowledge the Pawsey Supercomputing Centre which is supported by theWestern Australian and Australian Governments. Data were processed at the Pawsey Supercomputing Centre and at DownUnder GeoSolutions Pty Ltd. Simulations were undertaken on OzStar, Swinburne University.