Skip to main content Accessibility help
×
Home

Demonstration of polarisation calibration with the LBA on Selected AGNs

  • Thanapol Chanapote (a1) (a2) (a3), Richard Dodson (a2), Maria Rioja (a2) (a4) (a5), Kitiyanee Asanok (a1) (a3), Jamie Stevens (a6) and Iván Martí-Vidal (a7)...

Abstract

We present here the results from a full polarisation study, an important VLBI capability, of a selected set of bright Active Galactic Nuclei (AGNs), along with the steps required to fully calibrate the Australian Long Baseline Array. We compare strategies for high-precision polarisation measurements using two polarisation correction methods: (1) Linear model and (2) Ellipticity-Orientation model and two data-recording techniques: recording (1) nominally circular polarisation at all stations and (2) mixed polarisation, where all but one station record circular polarisation and the other recorded linear polarisation. The latter is corrected post-correlation. We explored these possible solution to discover which will best accommodate the heterogeneous nature of the Australian Long Baseline Array without impacting on the science results. The targets, all compact and of low polarisation fraction, allow us to compare multiple independent solutions for polarisation characteristics. The results show that the agreement between the two polarisation correction models is excellent. However, the values from Mopra with nominally circular polarisation are larger than would be acceptable. However, we also demonstrate that recording mixed polarisation modes and correcting post-correlation provide a high quality polarisation product. We report on the detailed tests of these strategies and assess that the array is ready for full polarisation operation.

Copyright

Corresponding author

Author for correspondence: T. Chanapote, E-mail: t.chanapote@gmail.com

References

Hide All
Bains, I., Caswell, J., Richards, A. M. S., Phillips, C., Tingay, S., Kramer, B. H., Cohen, R. J., & Cunningham, M. 2007, in IAU Symposium Vol. 621 242, Astrophysical Masers and Their Environments, eds. Chapman, J. M., &Baan, W. A., 64, doi:10.1017/S1743921307012574
Cotton, W. D. 1993, AJ, 106, 1241
Deller, A. T., et al. 2011, PASP, 123, 275
Dodson, R. 2007, Polarisation gain terms for VLBI with Nasmyth or E-W mounts. Technical report, http://www1.oan.es/informes/archivos/IT-OAN-2007-16.pdf. OAN, http://www1.oan.es/informes/archivos/IT-OAN-2007-16.pdf
Dodson, R. 2008, A&A, 480, 767
Dodson, R., & Tzioumis, A. 2013, Absolute polarisation calibration for LBA from ATCA data. Technical report, http://www.atnf.csiro.au/vlbi/evlbi/memos/elba_10_polarisation.pdf. ATNF, http://www.atnf.csiro.au/vlbi/evlbi/memos/elba_10_polarisation.pdf
Greisen, E. W. 2003, Inf. Handling Astron. - Hist. Vistas, 285, 109
Kemball, A. J., Diamond, P. J., & Cotton, W. D. 1995, A&AS, 110, 383
Lister, M. L., et al. 2009, AJ, 138, 1874
Martí-Vidal, I., Roy, A., Conway, J., & Zensus, A. J. 2016, A&A, 587, A143
McMullin, J. P., Waters, B., Schiebel, D., Young, W., & Golap, K. 2007, in Astronomical Data Analysis Software and Systems XVI, eds. Shaw, R. A., Hill, F., & Bell, D. J., Astronomical Society of the Pacific Conference Series, Orem, UT, USA Vol. 376, 127
Petrov, L. 2016, preprint arXiv:1610.04951
Petrov, L., Kovalev, Y. Y., Fomalont, E. B., & Gordon, D. 2008, AJ, 136, 580
Roberts, D. H., Wardle, J. F. C., & Brown, L. F. 1994, ApJ, 427, 718
Shepherd, M. C. 1997, in Astronomical Data Analysis Software and Systems VI, eds. Hunt, G., & Payne, H., Astronomical Society of the Pacific Conference Series, Orem, UT, USA Vol. 125, 77
Trippe, S. 2014, JKoAS, 47, 15
Wilson, W. E., et al. 2011, MNRAS, 416, 832

Keywords

Metrics

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed