First X/S VLBI experiment at station WARK12M
On 2011.02.14 VLBI antenna WARK12M located near Auckland, New Zealand
participated in VLBI experiment r1470. This was the second experiment
the station observed using X/S (8 GHz and 2.3 GHz) receivers.
On 2010.05.07 station participated in L-band geodesy experiment.
Station position in that experiment were derived with a decimeter
level of accuracy.
On 2011.02.24 experiment has been correlated in Bonn using DiFX software
correlator. Experiment can be considered as partially successful.
Fringes were detected at X and S-bands. However, the scheduled was
extremely unfavorable for position determination of WARK12M.
Station WARK12M was schedule in a tag-alone mode. That means the schedule
was prepared for the network without WARK12M, and then WARK12M was
added to observations of those sources which were above the horizon.
Since the closest station of the network was in 6.7 thousands km from
New Zealand, very few sources had a common visibility zone. Of 39
observations scheduled fringes were detected at 22 observations.
The listing of the solution is accessible here.
Results of position determination from r1470:
Total Adjustment to apriori Formal error
WARK12M 9999 AUST X Comp -5115325325.29 mm 572.708 mm 941.765 mm
WARK12M 9999 AUST Y Comp 477843761.25 mm 789.246 mm 227.851 mm
WARK12M 9999 AUST Z Comp -3767193677.16 mm 923.841 mm 969.263 mm
WARK12M 9999 U Comp -948.38 mm -948.383 mm 1335.313 mm
WARK12M 9999 E Comp -839.09 mm -839.092 mm 146.498 mm
WARK12M 9999 N Comp 448.20 mm 448.196 mm 271.632 mm
The formal uncertainties are a factor of 2—5 greater than
in the L-band astrometry experiment, although the systematic
errors are presumably less.
Problems
No signal was found S-band lost two IFs: IF5, and IF6.
(Comment from Tim Natush: there was an error in frequency setup, will
be fixed in next experiment.) The fringes are
detected in IF1 at S-band. These three IFs were removed from fringe
fitting. The maximal SNR at X-band 46.4 and at S-band 26.2, which makes
difficult to make analysis in depth. No other abnormalities were found.
Autocorrelation at X-band shows a strange patter at IF8.
Amplitude analysis will be done later.
Fringes plots
Fringe phase in radians is shown in green color; fringe
amplitude is shown in blue color.
S-band
X-band
S-band autocorrelation
X-band autocorrelation
Zoom of first two IFs:
Zoom of the last IFs:
References
L. Petrov, C. Phillips, T. Tzioumis, B. Stansby, C. Reynolds,
H. E. Bignall, S. Gulyaev, T. Natusch, N. Palmer, D. Collett,
J. E. Reynolds, S. W. Amy, R. Wayth, S. J. Tingay,
First geodetic observations using new VLBI stations ASKAP-29
and WARK12M, accepted by Publ. Astronom. Soc. Australia, 2010,
http://arxiv.org/abs/1012.4243
Back to Leonid Petrov's discussion page.
Last update: 2011.02.25_00:31:21