Detection of the Epoch of Reionisation using the Murchison Widefield Array

The Challenge

The neutral hydrogen 21cm emission line signal is exceptionally weak, drowned in the radio light from galaxies between it and us, and also by human-generated radio interference here on Earth. We need to observe this signal in a remote site, deep in the Western Australian outback, and collect data for thousands of hours, in order to achieve the clarity of signal required for detection. This results in enormous amounts of data, located at a remote site, requiring excellent data transport and storage, and data processing resources. Moreover, the telescope itself adds a large amount of complexity, imprinting its own properties on the data, and requiring careful characterisation and treatment.

The Solution

To undertake this experiment, the instrument, data transport and data analysis need to work together to form a cohesive program. The raw data are too large to retain and access easily, and therefore rapid transport, storage and pre-processing are required for a manageable and achievable science outcome.

The Outcome

Together with the fast data link from the site to the Pawsey Supercomputing and Research Centre in Perth, via Geraldton, the supercomputing, data moving and data storage resources at Pawsey allow us rapid access to data, and effective data processing and analysis. Pawsey’s supercomputers have all of the software and applications required for us to process the data from raw to final science products

List of Publications

@ARTICLE{2021MNRAS.508.5954R,
author = {{Rahimi}, M. and {Pindor}, B. and {Line}, J.~L.~B. and {Barry}, N. and {Trott}, C.~M. and {Webster}, R.~L. and {Jordan}, C.~H. and {Wilensky}, M. and {Yoshiura}, S. and {Beardsley}, A. and {Bowman}, J. and {Byrne}, R. and {Chokshi}, A. and {Hazelton}, B.~J. and {Hasegawa}, K. and {Howard}, E. and {Greig}, B. and {Jacobs}, D. and {Joseph}, R. and {Kolopanis}, M. and {Lynch}, C. and {McKinley}, B. and {Mitchell}, D.~A. and {Murray}, S. and {Morales}, M.~F. and {Pober}, J.~C. and {Takahashi}, K. and {Tingay}, S.~J. and {Wayth}, R.~B. and {Wyithe}, J.~S.~B. and {Zheng}, Q.},
title = “{Epoch of reionization power spectrum limits from Murchison Widefield Array data targeted at EoR1 field}”,
journal = {\mnras},
keywords = {methods: data analysis, methods: observational, techniques: interferometric, (cosmology:) dark ages, reionization, first stars, Astrophysics – Cosmology and Nongalactic Astrophysics, Astrophysics – Instrumentation and Methods for Astrophysics},
year = 2021,
month = dec,
volume = {508},
number = {4},
pages = {5954-5971},
doi = {10.1093/mnras/stab2918},
archivePrefix = {arXiv},
eprint = {2110.03190},
primaryClass = {astro-ph.CO},
adsurl = {https://ui.adsabs.harvard.edu/abs/2021MNRAS.508.5954R},
adsnote = {Provided by the SAO/NASA Astrophysics Data System}
}

@ARTICLE{2021PASA…38…57L,
author = {{Lynch}, C.~R. and {Galvin}, T.~J. and {Line}, J.~L.~B. and {Jordan}, C.~H. and {Trott}, C.~M. and {Chege}, J.~K. and {McKinley}, B. and {Johnston-Hollitt}, M. and {Tingay}, S.~J.},
title = “{The MWA long baseline Epoch of reionisation survey{\textemdash}I. Improved source catalogue for the EoR 0 field}”,
journal = {\pasa},
keywords = {surveys, radio interferometry, radio continuum emission, cosmology, reionisation, Astrophysics – Cosmology and Nongalactic Astrophysics, Astrophysics – Instrumentation and Methods for Astrophysics},
year = 2021,
month = nov,
volume = {38},
eid = {e057},
pages = {e057},
doi = {10.1017/pasa.2021.50},
archivePrefix = {arXiv},
eprint = {2110.08400},
primaryClass = {astro-ph.CO},
adsurl = {https://ui.adsabs.harvard.edu/abs/2021PASA…38…57L},
adsnote = {Provided by the SAO/NASA Astrophysics Data System}
}

@ARTICLE{2021MNRAS.tmp.2990B,
author = {{Byrne}, Ruby and {Morales}, Miguel F. and {Hazelton}, Bryna and {Sullivan}, Ian and {Barry}, Nichole and {Lynch}, Christene and {Line}, Jack L.~B. and {Jacobs}, Daniel C.},
title = “{A map of diffuse radio emission at 182 MHz to enhance epoch of reionization observations in the southern hemisphere}”,
journal = {\mnras},
keywords = {Cosmology: dark ages, reionization, first stars, surveys, polarization, Techniques: interferometric, Techniques: polarimetric, Astrophysics – Cosmology and Nongalactic Astrophysics, Astrophysics – Instrumentation and Methods for Astrophysics},
year = 2021,
month = nov,
doi = {10.1093/mnras/stab3276},
archivePrefix = {arXiv},
eprint = {2107.11487},
primaryClass = {astro-ph.CO},
adsurl = {https://ui.adsabs.harvard.edu/abs/2021MNRAS.tmp.2990B},
adsnote = {Provided by the SAO/NASA Astrophysics Data System}
}

@ARTICLE{2021arXiv211006173B,
author = {{Barry}, Nichole and {Bernardi}, Gianni and {Greig}, Bradley and {Kern}, Nicholas and {Mertens}, Florent},
title = “{SKA-Low Intensity Mapping Pathfinder Updates: Deeper 21 cm Power Spectrum Limits from Improved Analysis Frameworks}”,
journal = {arXiv e-prints},
keywords = {Astrophysics – Cosmology and Nongalactic Astrophysics, Astrophysics – Instrumentation and Methods for Astrophysics},
year = 2021,
month = oct,
eid = {arXiv:2110.06173},
pages = {arXiv:2110.06173},
archivePrefix = {arXiv},
eprint = {2110.06173},
primaryClass = {astro-ph.CO},
adsurl = {https://ui.adsabs.harvard.edu/abs/2021arXiv211006173B},
adsnote = {Provided by the SAO/NASA Astrophysics Data System}
}

@ARTICLE{2021MNRAS.507..772T,
author = {{Trott}, C.~M. and {Jordan}, C.~H. and {Line}, J.~L.~B. and {Lynch}, C.~R. and {Yoshiura}, S. and {McKinley}, B. and {Dayal}, P. and {Pindor}, B. and {Hutter}, A. and {Takahashi}, K. and {Wayth}, R.~B. and {Barry}, N. and {Beardsley}, A. and {Bowman}, J. and {Byrne}, R. and {Chokshi}, A. and {Greig}, B. and {Hasegawa}, K. and {Hazelton}, B.~J. and {Howard}, E. and {Jacobs}, D. and {Kolopanis}, M. and {Mitchell}, D.~A. and {Morales}, M.~F. and {Murray}, S. and {Pober}, J.~C. and {Rahimi}, M. and {Tingay}, S.~J. and {Webster}, R.~L. and {Wilensky}, M. and {Wyithe}, J.~S.~B. and {Zheng}, Q.},
title = “{Constraining the 21 cm brightness temperature of the IGM at z = 6.6 around LAEs with the murchison widefield array}”,
journal = {\mnras},
keywords = {instrumentation: interferometers, methods: statistical, Astrophysics – Cosmology and Nongalactic Astrophysics, Astrophysics – Instrumentation and Methods for Astrophysics},
year = 2021,
month = oct,
volume = {507},
number = {1},
pages = {772-780},
doi = {10.1093/mnras/stab2235},
archivePrefix = {arXiv},
eprint = {2107.14493},
primaryClass = {astro-ph.CO},
adsurl = {https://ui.adsabs.harvard.edu/abs/2021MNRAS.507..772T},
adsnote = {Provided by the SAO/NASA Astrophysics Data System}
}

@ARTICLE{2021MNRAS.505.4775Y,
author = {{Yoshiura}, S. and {Pindor}, B. and {Line}, J.~L.~B. and {Barry}, N. and {Trott}, C.~M. and {Beardsley}, A. and {Bowman}, J. and {Byrne}, R. and {Chokshi}, A. and {Hazelton}, B.~J. and {Hasegawa}, K. and {Howard}, E. and {Greig}, B. and {Jacobs}, D. and {Jordan}, C.~H. and {Joseph}, R. and {Kolopanis}, M. and {Lynch}, C. and {McKinley}, B. and {Mitchell}, D.~A. and {Morales}, M.~F. and {Murray}, S.~G. and {Pober}, J.~C. and {Rahimi}, M. and {Takahashi}, K. and {Tingay}, S.~J. and {Wayth}, R.~B. and {Webster}, R.~L. and {Wilensky}, M. and {Wyithe}, J.~S.~B. and {Zhang}, Z. and {Zheng}, Q.},
title = “{A new MWA limit on the 21 cm power spectrum at redshifts 13-17}”,
journal = {\mnras},
keywords = {methods: data analysis, dark ages, reionization, first stars, Astrophysics – Cosmology and Nongalactic Astrophysics},
year = 2021,
month = aug,
volume = {505},
number = {4},
pages = {4775-4790},
doi = {10.1093/mnras/stab1560},
archivePrefix = {arXiv},
eprint = {2105.12888},
primaryClass = {astro-ph.CO},
adsurl = {https://ui.adsabs.harvard.edu/abs/2021MNRAS.505.4775Y},
adsnote = {Provided by the SAO/NASA Astrophysics Data System}
}

@ARTICLE{2021PASA…38…28C,
author = {{Chege}, J. Kariuki and {Jordan}, C.~H. and {Lynch}, C. and {Line}, J.~L.~B. and {Trott}, C.~M.},
title = “{Simulations of ionospheric refraction on radio interferometric data}”,
journal = {\pasa},
keywords = {atmospheric effects, plasmas, instrumentation: interferometers, Algorithms, Astrophysics – Instrumentation and Methods for Astrophysics, Astrophysics – Astrophysics of Galaxies},
year = 2021,
month = jun,
volume = {38},
eid = {e028},
pages = {e028},
doi = {10.1017/pasa.2021.22},
archivePrefix = {arXiv},
eprint = {2105.04215},
primaryClass = {astro-ph.IM},
adsurl = {https://ui.adsabs.harvard.edu/abs/2021PASA…38…28C},
adsnote = {Provided by the SAO/NASA Astrophysics Data System}
}

@ARTICLE{2021MNRAS.502.1990C,
author = {{Chokshi}, A. and {Line}, J.~L.~B. and {Barry}, N. and {Ung}, D. and {Kenney}, D. and {McPhail}, A. and {Williams}, A. and {Webster}, R.~L.},
title = “{Dual polarization measurements of MWA beampatterns at 137 MHz}”,
journal = {\mnras},
keywords = {instrumentation: interferometers, methods: observational, site testing, Astrophysics – Instrumentation and Methods for Astrophysics},
year = 2021,
month = apr,
volume = {502},
number = {2},
pages = {1990-2004},
doi = {10.1093/mnras/stab156},
archivePrefix = {arXiv},
eprint = {2102.00402},
primaryClass = {astro-ph.IM},
adsurl = {https://ui.adsabs.harvard.edu/abs/2021MNRAS.502.1990C},
adsnote = {Provided by the SAO/NASA Astrophysics Data System}
}

@ARTICLE{2021MNRAS.501..367W,
author = {{Watkinson}, Catherine A. and {Trott}, Cathryn M. and {Hothi}, Ian},
title = “{The bispectrum and 21-cm foregrounds during the Epoch of Reionization}”,
journal = {\mnras},
keywords = {methods: statistical, intergalactic medium, dark ages, reionization, first stars, cosmology: theory, Astrophysics – Cosmology and Nongalactic Astrophysics},
year = 2021,
month = jan,
volume = {501},
number = {1},
pages = {367-382},
doi = {10.1093/mnras/staa3677},
archivePrefix = {arXiv},
eprint = {2002.05992},
primaryClass = {astro-ph.CO},
adsurl = {https://ui.adsabs.harvard.edu/abs/2021MNRAS.501..367W},
adsnote = {Provided by the SAO/NASA Astrophysics Data System}
}

@ARTICLE{2021MNRAS.500.5322G,
author = {{Greig}, Bradley and {Trott}, Cathryn M. and {Barry}, Nichole and {Mutch}, Simon J. and {Pindor}, Bart and {Webster}, Rachel L. and {Wyithe}, J. Stuart B.},
title = “{Exploring reionization and high-z galaxy observables with recent multiredshift MWA upper limits on the 21-cm signal}”,
journal = {\mnras},
keywords = {galaxies: high-redshift, intergalactic medium, dark ages, reionization, first stars, diffuse radiation, early Universe, cosmology: theory, Astrophysics – Cosmology and Nongalactic Astrophysics},
year = 2021,
month = jan,
volume = {500},
number = {4},
pages = {5322-5335},
doi = {10.1093/mnras/staa3494},
archivePrefix = {arXiv},
eprint = {2008.02639},
primaryClass = {astro-ph.CO},
adsurl = {https://ui.adsabs.harvard.edu/abs/2021MNRAS.500.5322G},
adsnote = {Provided by the SAO/NASA Astrophysics Data System}