A new MWA limit on the 21 cm power spectrum at redshifts ∼13-17
Observations in the lowest Murchison Widefield Array (MWA) band between 75 and 100 MHz have the potential to constrain the distribution of neutral hydrogen in the intergalactic medium at redshift ∼13-17. Using 15 h of MWA data, we analyse systematics in this band such as radio-frequency interference...
| Main Authors: | , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , |
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| Format: | Journal Article |
| Language: | English |
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OXFORD UNIV PRESS
2021
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| Online Access: | http://dx.doi.org/10.1093/mnras/stab1560 http://hdl.handle.net/20.500.11937/91573 |
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| author | Yoshiura, S. Pindor, B. Line, J.L.B. Barry, Nichole Trott, Cathryn Beardsley, A. Bowman, J. Byrne, R. Chokshi, A. Hazelton, B.J. Hasegawa, K. Howard, E. Greig, B. Jacobs, D. Jordan, Chris Joseph, R. Kolopanis, M. Lynch, Christene McKinley, Ben Mitchell, D.A. Morales, M.F. Murray, Steven Pober, J.C. Rahimi, M. Takahashi, K. Tingay, Steven Wayth, Randall Webster, R.L. Wilensky, M. Wyithe, J.S.B. Zhang, Z. Zheng, Q. |
| author_facet | Yoshiura, S. Pindor, B. Line, J.L.B. Barry, Nichole Trott, Cathryn Beardsley, A. Bowman, J. Byrne, R. Chokshi, A. Hazelton, B.J. Hasegawa, K. Howard, E. Greig, B. Jacobs, D. Jordan, Chris Joseph, R. Kolopanis, M. Lynch, Christene McKinley, Ben Mitchell, D.A. Morales, M.F. Murray, Steven Pober, J.C. Rahimi, M. Takahashi, K. Tingay, Steven Wayth, Randall Webster, R.L. Wilensky, M. Wyithe, J.S.B. Zhang, Z. Zheng, Q. |
| author_sort | Yoshiura, S. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | Observations in the lowest Murchison Widefield Array (MWA) band between 75 and 100 MHz have the potential to constrain the distribution of neutral hydrogen in the intergalactic medium at redshift ∼13-17. Using 15 h of MWA data, we analyse systematics in this band such as radio-frequency interference (RFI), ionospheric and wide field effects. By updating the position of point sources, we mitigate the direction-independent calibration error due to ionospheric offsets. Our calibration strategy is optimized for the lowest frequency bands by reducing the number of direction-dependent calibrators and taking into account radio sources within a wider field of view. We remove data polluted by systematics based on the RFI occupancy and ionospheric conditions, finally selecting 5.5 h of the cleanest data. Using these data, we obtain 2σ upper limits on the 21 cm power spectrum in the range of 0.1 h Mpc-1 ≲ k ≲ 1 h Mpc-1 and at z = 14.2, 15.2, and 16.5, with the lowest limit being 6.3 × 106 mK2 at k=0.14 h Mpc-1 and at z = 15.2 with a possibility of a few per cent of signal loss due to direction-independent calibration. |
| first_indexed | 2025-11-14T11:37:03Z |
| format | Journal Article |
| id | curtin-20.500.11937-91573 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| language | English |
| last_indexed | 2025-11-14T11:37:03Z |
| publishDate | 2021 |
| publisher | OXFORD UNIV PRESS |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-915732023-05-16T02:11:01Z A new MWA limit on the 21 cm power spectrum at redshifts ∼13-17 Yoshiura, S. Pindor, B. Line, J.L.B. Barry, Nichole Trott, Cathryn Beardsley, A. Bowman, J. Byrne, R. Chokshi, A. Hazelton, B.J. Hasegawa, K. Howard, E. Greig, B. Jacobs, D. Jordan, Chris Joseph, R. Kolopanis, M. Lynch, Christene McKinley, Ben Mitchell, D.A. Morales, M.F. Murray, Steven Pober, J.C. Rahimi, M. Takahashi, K. Tingay, Steven Wayth, Randall Webster, R.L. Wilensky, M. Wyithe, J.S.B. Zhang, Z. Zheng, Q. Science & Technology Physical Sciences Astronomy & Astrophysics methods: data analysis dark ages, reionization, first stars MURCHISON WIDEFIELD ARRAY COSMIC DAWN FUNDAMENTAL LIMITATIONS NEUTRAL HYDROGEN LIGHT-CONE EPOCH REIONIZATION CALIBRATION SIGNAL LOFAR astro-ph.CO astro-ph.CO Observations in the lowest Murchison Widefield Array (MWA) band between 75 and 100 MHz have the potential to constrain the distribution of neutral hydrogen in the intergalactic medium at redshift ∼13-17. Using 15 h of MWA data, we analyse systematics in this band such as radio-frequency interference (RFI), ionospheric and wide field effects. By updating the position of point sources, we mitigate the direction-independent calibration error due to ionospheric offsets. Our calibration strategy is optimized for the lowest frequency bands by reducing the number of direction-dependent calibrators and taking into account radio sources within a wider field of view. We remove data polluted by systematics based on the RFI occupancy and ionospheric conditions, finally selecting 5.5 h of the cleanest data. Using these data, we obtain 2σ upper limits on the 21 cm power spectrum in the range of 0.1 h Mpc-1 ≲ k ≲ 1 h Mpc-1 and at z = 14.2, 15.2, and 16.5, with the lowest limit being 6.3 × 106 mK2 at k=0.14 h Mpc-1 and at z = 15.2 with a possibility of a few per cent of signal loss due to direction-independent calibration. 2021 Journal Article http://hdl.handle.net/20.500.11937/91573 10.1093/mnras/stab1560 English http://dx.doi.org/10.1093/mnras/stab1560 http://purl.org/au-research/grants/arc/CE170100013 http://purl.org/au-research/grants/arc/DE140100316 http://purl.org/au-research/grants/arc/CE110001020 OXFORD UNIV PRESS fulltext |
| spellingShingle | Science & Technology Physical Sciences Astronomy & Astrophysics methods: data analysis dark ages, reionization, first stars MURCHISON WIDEFIELD ARRAY COSMIC DAWN FUNDAMENTAL LIMITATIONS NEUTRAL HYDROGEN LIGHT-CONE EPOCH REIONIZATION CALIBRATION SIGNAL LOFAR astro-ph.CO astro-ph.CO Yoshiura, S. Pindor, B. Line, J.L.B. Barry, Nichole Trott, Cathryn Beardsley, A. Bowman, J. Byrne, R. Chokshi, A. Hazelton, B.J. Hasegawa, K. Howard, E. Greig, B. Jacobs, D. Jordan, Chris Joseph, R. Kolopanis, M. Lynch, Christene McKinley, Ben Mitchell, D.A. Morales, M.F. Murray, Steven Pober, J.C. Rahimi, M. Takahashi, K. Tingay, Steven Wayth, Randall Webster, R.L. Wilensky, M. Wyithe, J.S.B. Zhang, Z. Zheng, Q. A new MWA limit on the 21 cm power spectrum at redshifts ∼13-17 |
| title | A new MWA limit on the 21 cm power spectrum at redshifts ∼13-17 |
| title_full | A new MWA limit on the 21 cm power spectrum at redshifts ∼13-17 |
| title_fullStr | A new MWA limit on the 21 cm power spectrum at redshifts ∼13-17 |
| title_full_unstemmed | A new MWA limit on the 21 cm power spectrum at redshifts ∼13-17 |
| title_short | A new MWA limit on the 21 cm power spectrum at redshifts ∼13-17 |
| title_sort | new mwa limit on the 21 cm power spectrum at redshifts ∼13-17 |
| topic | Science & Technology Physical Sciences Astronomy & Astrophysics methods: data analysis dark ages, reionization, first stars MURCHISON WIDEFIELD ARRAY COSMIC DAWN FUNDAMENTAL LIMITATIONS NEUTRAL HYDROGEN LIGHT-CONE EPOCH REIONIZATION CALIBRATION SIGNAL LOFAR astro-ph.CO astro-ph.CO |
| url | http://dx.doi.org/10.1093/mnras/stab1560 http://dx.doi.org/10.1093/mnras/stab1560 http://dx.doi.org/10.1093/mnras/stab1560 http://dx.doi.org/10.1093/mnras/stab1560 http://hdl.handle.net/20.500.11937/91573 |