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A High-Resolution Foreground Model for the MWA EoR1 Field: Model and Implications for EoR Power Spectrum Analysis

  • P. Procopio (a1) (a2), R. B. Wayth (a2) (a3), J. Line (a1) (a2), C. M. Trott (a2) (a3), H. T. Intema (a4) (a5), D. A. Mitchell (a6), B. Pindor (a1) (a2), J. Riding (a1), S. J. Tingay (a3) (a7), M. E. Bell (a2) (a6), J. R. Callingham (a8), K. S. Dwarakanath (a9), Bi-Qing For (a10), B. M. Gaensler (a2) (a8) (a11), P. J. Hancock (a3), L. Hindson (a12), N. Hurley-Walker (a3), M. Johnston-Hollitt (a12) (a13), A. D. Kapińska (a2) (a10), E. Lenc (a2) (a14), B. McKinley (a1) (a2), J. Morgan (a3), A. Offringa (a8), L. Staveley-Smith (a2) (a10), Chen Wu (a10) and Q. Zheng (a12) (a13)...
Abstract
Abstract

The current generation of experiments aiming to detect the neutral hydrogen signal from the Epoch of Reionisation (EoR) is likely to be limited by systematic effects associated with removing foreground sources from target fields. In this paper, we develop a model for the compact foreground sources in one of the target fields of the MWA’s EoR key science experiment: the ‘EoR1’ field. The model is based on both the MWA’s GLEAM survey and GMRT 150 MHz data from the TGSS survey, the latter providing higher angular resolution and better astrometric accuracy for compact sources than is available from the MWA alone. The model contains 5 049 sources, some of which have complicated morphology in MWA data, Fornax A being the most complex. The higher resolution data show that 13% of sources that appear point-like to the MWA have complicated morphology such as double and quad structure, with a typical separation of 33 arcsec. We derive an analytic expression for the error introduced into the EoR two-dimensional power spectrum due to peeling close double sources as single point sources and show that for the measured source properties, the error in the power spectrum is confined to high k modes that do not affect the overall result for the large-scale cosmological signal of interest. The brightest 10 mis-modelled sources in the field contribute 90% of the power bias in the data, suggesting that it is most critical to improve the models of the brightest sources. With this hybrid model, we reprocess data from the EoR1 field and show a maximum of 8% improved calibration accuracy and a factor of two reduction in residual power in k-space from peeling these sources. Implications for future EoR experiments including the SKA are discussed in relation to the improvements obtained.

Copyright
Corresponding author
15 E-mail: pietro.procopio@unimelb.edu.au
References
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Barry N., Hazelton B., Sullivan I., Morales M. F., & Pober J. C. 2016, MNRAS, 461, 3135 10.1093/mnras/stw1380 2016MNRAS.461.3135B
Beardsley A. P., et al. 2016, ApJ, 833, 102 10.3847/1538-4357/833/1/102 2016ApJ...833..102B
Bernardi G., et al. 2009, A&A, 500, 965 10.1051/0004-6361/200911627 2009A&A...500..965B
Bernardi G., et al. 2013, ApJ, 771, 105 10.1088/0004-637X/771/2/105 2013ApJ...771..105B
Bowman J. D., et al. 2013, PASA, 30, 31 10.1017/pas.2013.009 2013PASA...30...31B
Braun R. 2016, SKA Key Document No. 641
Chapman E., et al. 2012, MNRAS, 423, 2518 10.1111/j.1365-2966.2012.21065.x 2012MNRAS.423.2518C
Condon J. J., Cotton W. D., Greisen E. W., Yin Q. F., Perley R. A., Taylor G. B., & Broderick J. J. 1998, AJ 10.1086/300337, 115, 1693
Datta A., Bowman J. D., & Carilli C. L. 2010, ApJ, 724, 526 10.1088/0004-637X/724/1/526 2010ApJ...724..526D
DeBoer D. R., et al. 2017, PASP, 129, 975 2016arXiv160607473D
Di Matteo T., Perna R., Abel T., & Rees M. J. 2002, ApJ, 564, 576
Dillon J. S., & Parsons A. R. 2016, ApJ, 826, 181 10.3847/0004-637X/826/2/181 2016ApJ...826..181D
Dillon J. S., et al. 2014, PhRvD, 89, 023002 10.1103/PhysRevD.89.023002 2014PhRvD..89b3002D
Ewall-Wice A., Dillon J. S., Liu A., & Hewitt J. 2017, MNRAS, 470, 2 2016arXiv161002689E
Gervasi M., Tartari A., Zannoni M., Boella G., & Sironi G. 2008, ApJ, 682, 223 10.1086/588628 2008ApJ...682..223G
Hurley-Walker N., et al. 2017, MNRAS, 464, 1146 10.1093/mnras/stw2337 2017MNRAS.464.1146H
Intema H. T., Jagannathan P., Mooley K. P., & Frail D. A. 2017, A&A, 598, A78 10.1051/0004-6361/201628536 2017A&A...598A..78I
Intema H. T., van der Tol S., Cotton W. D., Cohen A. S., van Bemmel I. M., & Röttgering H. J. A. 2009, A&A, 501, 1185 10.1051/0004-6361/200811094 2009A&A...501.1185I
Intema H. T., van Weeren R. J., Röttgering H. J. A., & Lal D. V. 2011, A&A, 535, A38 10.1051/0004-6361/201014253
Jacobs D. C., et al. 2016, ApJ, 825, 114 10.3847/0004-637X/825/2/114 2016ApJ...825..114J
Jelić V., Zaroubi S., Labropoulos P., Bernardi G., de Bruyn A. G., & Koopmans L. V. E. 2010, MNRAS, 409, 1647 10.1111/j.1365-2966.2010.17407.x 2010MNRAS.409.1647J
Jelić V., et al. 2008, MNRAS, 389, 1319 10.1111/j.1365-2966.2008.13634.x 2008MNRAS.389.1319J
Koopmans L., et al. 2015, in Proc. of Advancing Astrophysics with the Square Kilometre Array (AASKA14), eds. Bourke T. L. et al. (Thatcham: Dolman Scott Ltd.), 1529 2015aska.confE...1K
Lane W. M., Cotton W. D., Helmboldt J. F., & Kassim N. E. 2012, RaSc, 47 10.1029/2011RS004941
Large M. I., Mills B. Y., Little A. G., Crawford D. F., & Sutton J. M. 1981, MNRAS, 194, 693
Lenc E., et al. 2016, ApJ, 830, 38 10.3847/0004-637X/830/1/38 2016ApJ...830...38L
Line J. L. B., Webster R. L., Pindor B., Mitchell D. A., & Trott C. M. 2017, PASA, 34, 3 10.1017/pasa.2016.58 2017PASA...34....3L
Mauch T., Murphy T., Buttery H. J., Curran J., Hunstead R. W., Piestrzynski B., Robertson J. G., & Sadler E. M. 2003, MNRAS, 342, 1117 10.1046/j.1365-8711.2003.06605.x
Mitchell D. A., Greenhill L. J., Wayth R. B., Sault R. J., Lonsdale C. J., Cappallo R. J., Morales M. F., & Ord S. M. 2008, ISTSP, 2, 707 10.1109/JSTSP.2008.2005327 2008ISTSP...2..707M
Morales M. F., Bowman J. D., Cappallo R., Hewitt J. N., & Lonsdale C. J. 2006, NewAR, 50, 173 10.1016/j.newar.2005.11.033 2006NewAR..50..173M
Morales M. F., Hazelton B., Sullivan I., & Beardsley A. 2012, ApJ, 752, 137 10.1088/0004-637X/752/2/137 2012ApJ...752..137M
Noordam J. E. 2004, in Proc. SPIE Vol. 5489, Ground-Based Telescopes, ed. Oschmann J. M. Jr. (Bellingham: SPIE), 817
Offringa A. R., et al. 2016, MNRAS, 458, 1057 10.1093/mnras/stw310 2016MNRAS.458.1057O
Parsons A. R., et al. 2010, AJ, 139, 1468
Parsons A. R., et al. 2014, ApJ, 788, 106 10.1088/0004-637X/788/2/106 2014ApJ...788..106P
Patil A. H., et al. 2016, MNRAS, 463, 4317 10.1093/mnras/stw2277 2016MNRAS.463.4317P
Scott D. W., ed. 1992, Multivariate Density Estimation. Wiley Series in Probability and Statistics (Hoboken: John Wiley & Sons, Inc.)
Swarup G. 1991, in ASP Conf. Ser. Vol. 19, IAU Colloq. 131: Radio Interferometry: Theory, Techniques, and Applications, eds. Cornwell T. J. & Perley R. A. (San Francisco: ASP), 376
Thyagarajan N., et al. 2013, ApJ, 776, 6 10.1088/0004-637X/776/1/6 2013ApJ...776....6T
Thyagarajan N., et al. 2015, ApJ, 804, 14
Tingay S. J., et al. 2013, PASA, 30, 7 10.1017/pasa.2012.007 2013PASA...30....7T
Trott C. M., & Wayth R. B. 2016, PASA, 33, 19 10.1017/pasa.2016.18 2016PASA...33...19T
Trott C. M., Wayth R. B., & Tingay S. J. 2012, ApJ, 757, 101 10.1088/0004-637X/757/1/101 2012ApJ...757..101T
Trott C. M., et al. 2016, ApJ, 818, 139 10.3847/0004-637X/818/2/139 2016ApJ...818..139T
van Haarlem M. P., et al. 2013, A&A, 556, A2 10.1051/0004-6361/201220873 2013A&A...556A...2V
Vedantham H., Udaya Shankar N., & Subrahmanyan R. 2012, ApJ, 745, 176
Wayth R. B., et al. 2015, PASA, 32, 25 10.1017/pasa.2015.26 2015PASA...32...25W
Zaldarriaga M., Furlanetto S. R., & Hernquist L. 2004, ApJ, 608, 622
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