LBA Calibrator Survey (LCS)


Objectives of the campaign

The goal of this VLBI project is to observe at 8.4 GHz a list of candidate flat spectrum radio sources with declinations < -30° with using the Australian LBA instrument and to 1) determine their position with milliarcsec accuracy; 2) measure their correlated flux density; 3) determine their suitability as calibrators for phase referencing observations and as target for astrometry and geodesy observations.

Preliminary results

Published results

The detailed description of the scheduling and data analysis technique and the catalogue from results of first four epochs,
LCS1 catalogue, can be found in L. Petrov, C., Phillips, A. Bertarini, T. Murphy, E. M. Sadler, "The LBA Calibrator Survey of southern compact extragalactic radio sources — LCS1", Mon. Not. Roy. Astron. Soc., 2011, 414(3), 2528–2539    http://arxiv.org/abs/1012.2607

Preliminary catalogue

Positions of 924 new objects among 1212 observed have been determined from analysis of 14 VLBI experiments with the LBA. Preliminary catalogue has been compiled. Correlated flux densities of observed sources have been computed. Brightness distributions, and images in FITS-format of 170 sources from segments v254a and v271e have been produced. Full dataset of brightness distributions and visibilities is accessible here: v254b and v271e.

Log files and results of processing of individual experiments

Log files and preliminary results of these campaign are accessible here.

People

Team members (in alphabetic order):

Previous Observations

On 2007.06.24_12:00 a 12 hour K-band experiment v230a with ATCA-104, CEDUNA, MOPRA, PARKES, HARTRAO HOBART26, SESHAN25 was observed. The primary goal of the experiment was to derive coordinates of stations ATCA-104, CEDUNA, MOPRA with centimeter accuracy. The secondary goal of the project was to check feasibility of running global astrometry experiments with the LBADR backend.

Five sources, never previously observed with the VLBA, were added to the schedule, two scans per source. All of them have been detected. Their positions were determined with 2–5 mas accuracies. Results of this experiment have been published at L. Petrov, C. Phillips, A. Bertarini, A. Deller, S. Pogrebenko, A. Mujunen, "The use of the Long Baseline Array in Australia for precise geodesy and absolute astrometry", Publications of the Astronomical Society of Australia, 26(1), 75-84, 2009. DOI: 10.1071/AS08030, Full text   (PDF, 308Kb).

This experiment has proved the concept. Detailed discussion related to the v230 experiment can be found here. Other details can be found here.

Proposed Observations

We requested sixteen 24 hour observing sessions at ATCA, Ceduna, Mopra, Hobart, Parkes, Hartrao, and Kath12M, Yaragedee, and Tidbinbilla if available for running X-band observations to determine coordinates at a milliarcsec accuracy level for ~1200 flat-spectrum sources in the declination zone [-40°, -90°]. We will also produce estimates of correlated flux density and source structure. The output catalogue of source positions will be of use for phase-referencing observations at the LBA, as a calibrator pool for the ATCA, ALMA, and SKA, for space navigation, and as a source list for geodetic observations. Considering success rate of 75 %, the pool of known southern calibrators is expected to increase by one order of magnitude.

Full text of the proposal for observations in 2007.
Full text of the proposal for observations in 2008.
Full text of the proposal for observations in 2009.
Full text of the proposal for observations in 2010.

List of candidates

The list of 1212 candidates was generated on a basis of the preliminary results AT20G catalogue. They were selected on the basis of their spectra: the sources with projected correlated flux density > 160 mJy and with the spectral index flatter than -0.6.

Current status

Data

(Suffix r after the session id in the file name denotes right circular polarization data, and suffix l denotes left circular polarization data). We waived proprietary period for all the data.

Exp Data in Mark-4 Fourfit format Data in FITS-IDI format
v254b 2008_02_05_v254br_mk4.tar.bz2 2008_02_05_v254br.fits.bz2
v271a 2008_08_10_v271ar_mk4.tar.bz2    2008_08_10_v271al_mk4.tar.bz2 2008_08_10_v271ar.fits.bz2    2008_08_10_v271al.fits.bz2
v271b 2008_11_28_v271br_mk4.tar.bz2 2008_11_28_v271br.fits.bz2
v271c 2009_07_04_v271cr_mk4.tar.bz2    2009_07_04_v271cl_mk4.tar.bz2 2009_07_04_v271cr.fits.bz2    2009_07_04_v271cl.fits.bz2
v271d 2009_12_12_v271dr_mk4.tar.bz2    2009_12_12_v271dl_mk4.tar.bz2 2009_12_12_v271dr.fits.bz2    2009_12_12_v271dl.fits.bz2
v271e 2010_03_11_v271e_rcp_mk4.tar.bz2    2010_03_11_v271e_lcp_mk4.tar.bz2 2010_03_11_v271e_fits.tar.bz2
v271f n/a 2010_03_11_v271f_fits.tar.bz2
v271g n/a 2010_10_29_v271g_01.fits
v271h n/a
2011_04_02_v271h_01.fits
2011_04_02_v271h_02.fits
2011_04_02_v271h_03.fits
2011_04_02_v271h_04.fits
2011_04_02_v271h_05.fits
2011_04_02_v271h_06.fits
2011_04_02_v271h_07.fits
2011_04_02_v271h_08.fits
2011_04_02_v271h_09.fits
2011_04_02_v271h_10.fits
2011_04_02_v271h_11.fits
2011_04_02_v271h_12.fits
2011_04_02_v271h_13.fits
2011_04_02_v271h_14.fits
2011_04_02_v271h_15.fits
2011_04_02_v271h_16.fits
2011_04_02_v271h_17.fits
2011_04_02_v271h_18.fits
2011_04_02_v271h_19.fits
2011_04_02_v271h_20.fits
2011_04_02_v271h_21.fits
2011_04_02_v271h_22.fits
2011_04_02_v271h_23.fits
2011_04_02_v271h_24.fits
2011_04_02_v271h_25.fits
2011_04_02_v271h_26.fits
2011_04_02_v271h_27.fits
2011_04_02_v271h_28.fits
2011_04_02_v271h_29.fits
2011_04_02_v271h_30.fits
2011_04_02_v271h_31.fits
v271i n/a
2011_07_23_v271i_01.fits
2011_07_23_v271i_02.fits
2011_07_23_v271i_03.fits
2011_07_23_v271i_04.fits
2011_07_23_v271i_05.fits
2011_07_23_v271i_06.fits
2011_07_23_v271i_07.fits
2011_07_23_v271i_08.fits
2011_07_23_v271i_09.fits
2011_07_23_v271i_10.fits
2011_07_23_v271i_11.fits
2011_07_23_v271i_12.fits
2011_07_23_v271i_13.fits
2011_07_23_v271i_14.fits
v271j n/a
2011_11_11_v271j_01.fits
2011_11_11_v271j_02.fits
2011_11_11_v271j_03.fits
2011_11_11_v271j_04.fits
2011_11_11_v271j_05.fits
2011_11_11_v271j_06.fits
2011_11_11_v271j_07.fits
2011_11_11_v271j_08.fits
2011_11_11_v271j_09.fits
2011_11_11_v271j_10.fits
2011_11_11_v271j_11.fits
2011_11_11_v271j_12.fits
v441a n/a
2011_11_12_v441a_01.fits
2011_11_12_v441a_02.fits
2011_11_12_v441a_03.fits
2011_11_12_v441a_04.fits
2011_11_12_v441a_05.fits
2011_11_12_v441a_06.fits
2011_11_12_v441a_07.fits
2011_11_12_v441a_08.fits
2011_11_12_v441a_09.fits
2011_11_12_v441a_10.fits
2011_11_12_v441a_11.fits
2011_11_12_v441a_12.fits
2011_11_12_v441a_13.fits
2011_11_12_v441a_14.fits
2011_11_12_v441a_15.fits
v271k n/a
2012_04_28_v271k_01.fits
2012_04_28_v271k_02.fits
2012_04_28_v271k_03.fits
2012_04_28_v271k_04.fits
2012_04_28_v271k_05.fits
2012_04_28_v271k_06.fits
2012_04_28_v271k_07.fits
2012_04_28_v271k_08.fits
2012_04_28_v271k_09.fits
2012_04_28_v271k_10.fits
2012_04_28_v271k_11.fits
2012_04_28_v271k_12.fits
v271l n/a
2013_03_15_v271l_01.fits
v271m n/a
2013_06_15_v271m_01.fits

Mailing list

Mailing list is for discussing issues related to the LCS experiments. Only subscribers can post messages to the list. The messages posted to the list are available for viewing to all from the mail archive.


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This page was prepared by Leonid Petrov ()
Last update: 2014.12.05_15:02:05