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The SFXC software correlator for very long baseline interferometry: algorithms and implementation

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Abstract

In this paper a description is given of the SFXC software correlator, developed and maintained at the Joint Institute for VLBI in Europe (JIVE). The software is designed to run on generic Linux-based computing clusters. The correlation algorithm is explained in detail, as are some of the novel modes that software correlation has enabled, such as wide-field VLBI imaging through the use of multiple phase centres and pulsar gating and binning. This is followed by an overview of the software architecture. Finally, the performance of the correlator as a function of number of CPU cores, telescopes and spectral channels is shown.

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Notes

  1. http://www.gnu.org/licenses/gpl-2.0.html

  2. http://gemini.gsfc.nasa.gov/solve

  3. B1937+21 has a rotational period P=1.56ms and D M=71cm−3pc [7]

  4. http://www.vlbi.org/vex/

  5. http://json.org

  6. Currently this is at 90 %

  7. http://www.aips.nrao.edu/

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Acknowledgments

Part of this work was made possible by the SCARiE project under the NWO STARE programme, and by the EC-funded EXPReS and NEXPReS projects, project numbers 026642 and RI-261525. GC and DAD acknowledge the EC FP7 project ESPaCE (grant agreement 263466). DAD and GMC acknowledge the EC FP7 project EuroPlaNet (grant agreement 228319). GMC acknowledges also the NWO-ShAO agreement on collaboration in VLBI. We thank Max Avruch and Ruud Oerlemans for their contributions during the early stages of SFXC development.

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Authors and Affiliations

  1. Joint Institute for VLBI in Europe, Oude Hoogeveensedijk 4, 7991, PD, Dwingeloo, Netherlands

    A. Keimpema, M. M. Kettenis, S. V. Pogrebenko, R. M. Campbell, G. Cimó, D. A. Duev, B. Eldering, H. J. van Langevelde, G. Molera Calvés, Z. Paragi & A. Szomoru

  2. Sterrewacht Leiden, Leiden University, P.O. Box 9513, 2300, RA, Leiden, Netherland

    H. J. van Langevelde

  3. Cruden B.V., Pedro de Medinalaan 25, 1086, XP, Amsterdam, Netherland

    N. Kruithof

  4. Laboratoire d’Informatique Fondamentale de Lille (LIFL), University of Lille, Cité scientifique - Bâtiment M3, 9655, Villeneuve d’Ascq Cédex, France

    D. Marchal

  5. Energieonderzoek Centrum Nederland (ECN), P.O.Box 1, 1755, ZG, Petten, Netherland

    H. Ozdemir

  6. School of Mathematics and Physics, University of Tasmania, Private Bag 37, Hobart, Tasmania, 7001, Australia

    Y. Pidopryhora

  7. Department of Earth and Space Sciences, Chalmers University of Technology, Onsala Space Observatory, 43992, Onsala, Sweden

    J. Yang

Authors
  1. A. Keimpema
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  2. M. M. Kettenis
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  3. S. V. Pogrebenko
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  4. R. M. Campbell
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  5. G. Cimó
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  6. D. A. Duev
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  7. B. Eldering
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  8. N. Kruithof
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  9. H. J. van Langevelde
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  10. D. Marchal
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  11. G. Molera Calvés
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  12. H. Ozdemir
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  13. Z. Paragi
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  14. Y. Pidopryhora
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  15. A. Szomoru
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  16. J. Yang
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Correspondence to A. Keimpema.

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Keimpema, A., Kettenis, M.M., Pogrebenko, S.V. et al. The SFXC software correlator for very long baseline interferometry: algorithms and implementation. Exp Astron 39, 259–279 (2015). https://doi.org/10.1007/s10686-015-9446-1

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  • DOI: https://doi.org/10.1007/s10686-015-9446-1

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