Search: onr:"swepub:oai:research.chalmers.se:fe4644f9-6042-4452-af77-3e2a415b15e1" >
Source finding in l...
Source finding in linear polarization for LOFAR, and SKA predecessor surveys, using Faraday moments
-
- Farnes, J.S. (author)
- Radboud Universiteit,Radboud University
-
- Heald, G. (author)
- Netherlands Institute for Radio Astronomy (ASTRON),Rijksuniversiteit Groningen,University of Groningen,Commonwealth Scientific and Industrial Research Organisation (CSIRO)
-
- Junklewitz, H. (author)
- Max Planck Gesellschaft zur Förderung der Wissenschaften e.V. (MPG),Max Planck Society for the Advancement of Science (MPG)
-
show more...
-
- Mulcahy, D. D. (author)
- University of Manchester
-
- Haverkorn, M. (author)
- Radboud Universiteit,Radboud University
-
- Van Eck, C.L. (author)
- Radboud Universiteit,Radboud University
-
- Riseley, C. J. (author)
- Commonwealth Scientific and Industrial Research Organisation (CSIRO),University of Manchester,University of Southampton
-
- Brentjens, M. (author)
- Netherlands Institute for Radio Astronomy (ASTRON)
-
- Horellou, Cathy, 1967 (author)
- Chalmers tekniska högskola,Chalmers University of Technology
-
- Vacca, V. (author)
- Istituto nazionale di astrofisica (INAF)
-
- Jones, D. I. (author)
- Radboud Universiteit,Radboud University
-
- Horneffer, A. (author)
- Max Planck Gesellschaft zur Förderung der Wissenschaften e.V. (MPG),Max Planck Society for the Advancement of Science (MPG)
-
- Paladino, R. (author)
- Istituto nazionale di astrofisica (INAF)
-
show less...
-
(creator_code:org_t)
- 2017-11-14
- 2018
- English.
-
In: Monthly Notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 474:3, s. 3280-3296
- Related links:
-
https://research.cha... (primary) (free)
-
show more...
-
https://academic.oup...
-
https://research.cha...
-
https://doi.org/10.1...
-
show less...
Abstract
Subject headings
Close
- The optimal source-finding strategy for linear polarization data is an unsolved problem, with many inhibitive factors imposed by the technically challenging nature of polarization observations. Such an algorithm is essential for Square Kilometre Array (SKA) pathfinder surveys, such as the Multifrequency Snapshot Sky Survey with the LOw Frequency ARray (LOFAR), as data volumes are significant enough to prohibit manual inspection. We present a new strategy of 'Faraday Moments' for source-finding in linear polarization with LOFAR, using the moments of the frequency-dependent full-Stokes data (i.e. the mean, standard deviation, skewness, and excess kurtosis). Through simulations of the sky, we find that moments can identify polarized sources with a high completeness: 98.5 per cent at a signal to noise of 5. While the method has low reliability, rotation measure (RM) synthesis can be applied per candidate source to filter out instrumental and spurious detections. This combined strategy will result in a complete and reliable catalogue of polarized sources that includes the full sensitivity of the observational bandwidth. We find that the technique can reduce the number of pixels on which RM Synthesis needs to be performed by a factor of ≈1 × 10 5 for source distributions anticipated with modern radio telescopes. Through tests on LOFAR data, we find that the technique works effectively in the presence of diffuse emission. Extensions of this method are directly applicable to other upcoming radio surveys such as the POlarization Sky Survey of the Universe's Magnetism with the Australia Square Kilometre Array Pathfinder, and the SKA itself.
Subject headings
- NATURVETENSKAP -- Geovetenskap och miljövetenskap -- Geofysik (hsv//swe)
- NATURAL SCIENCES -- Earth and Related Environmental Sciences -- Geophysics (hsv//eng)
- TEKNIK OCH TEKNOLOGIER -- Elektroteknik och elektronik -- Signalbehandling (hsv//swe)
- ENGINEERING AND TECHNOLOGY -- Electrical Engineering, Electronic Engineering, Information Engineering -- Signal Processing (hsv//eng)
- TEKNIK OCH TEKNOLOGIER -- Elektroteknik och elektronik -- Annan elektroteknik och elektronik (hsv//swe)
- ENGINEERING AND TECHNOLOGY -- Electrical Engineering, Electronic Engineering, Information Engineering -- Other Electrical Engineering, Electronic Engineering, Information Engineering (hsv//eng)
Keyword
- techniques: image processing
- Magnetic fields
- techniques: polarimetric
- Polarization
- methods: data analysis -methods: observational
Publication and Content Type
- art (subject category)
- ref (subject category)
Find in a library
To the university's database
- By the author/editor
-
Farnes, J.S.
-
Heald, G.
-
Junklewitz, H.
-
Mulcahy, D. D.
-
Haverkorn, M.
-
Van Eck, C.L.
-
show more...
-
Riseley, C. J.
-
Brentjens, M.
-
Horellou, Cathy, ...
-
Vacca, V.
-
Jones, D. I.
-
Horneffer, A.
-
Paladino, R.
-
show less...
- About the subject
-
- NATURAL SCIENCES
-
NATURAL SCIENCES
-
and Earth and Relate ...
-
and Geophysics
-
- ENGINEERING AND TECHNOLOGY
-
ENGINEERING AND ...
-
and Electrical Engin ...
-
and Signal Processin ...
-
- ENGINEERING AND TECHNOLOGY
-
ENGINEERING AND ...
-
and Electrical Engin ...
-
and Other Electrical ...
- Articles in the publication
-
Monthly Notices ...
- By the university
-
Chalmers University of Technology