EVN Network Monitoring Experiment (NME) Pipeline Feedback
Pipeline feedback for experiment N03C1.
If you have any comments on this experiment please email
the
address below.
Last updated: Mon Dec 15 14:48:43 CET 2003
zparagi@jive.nl
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General Comments.
(
Brief data summary and
scan listing.)
C-band NME observed on 29-30 October 2003 (session 3/2003). This experiment was recorded at 256 Mbps. Effelsberg and Westerbork used Mk5. Noto, Medicina, and Onsala recorded on Mk5 and tape. In Torun the recorder was broken. Noto also sent disk pack but the tape was processed (because tape was used in the session). Tracks 2 and 3 were dead, two channels had to be flagged. This affected all experiments.
Shanghai could see the sources only in the first half of the experiment. Some sources were below horizon for Ur and Hh, near the end of the observations.
There was an LO offset in Jodrell Bank which resulted in no fringes for the Lovell telescope. This affected the whole session after the fringe test. This may be fixed later. In Medicina the patch panel was badly configured for the RCP channels.
This is a preliminary pipeline processed with Tcal information from session 2/2003. Please send new rxg files to JIVE.
The ratio of expected to the observed number of visibilities is estimated as ERI = 0.442 (Ef=1, Mc=0.5, Jb=0, Wb=1, On=1, Nt=0.75, Ur=1.0 (1/2), Sh=1 (1/4), Hh=1, Tr=0). Some stations observed only in part of the experiment (and some only in 1 polarization), which is also indicated. The data losses were all due to technical problems. Leaving out Tr that did not participate in the observations, the ERI would have been 0.573.
Plots of the autocorrelations.
Comments.
Mc: bad RCP setup
Nt: two channels completely missing because of two dead tracks.
On: the autocorrelation amplitude was very low due to not ideal sampler statistics (this was corrected for before pipelining). Probably the whole session was affected.
Plots of the uncalibrated amplitude and phase against time.
Comments.
Mc: bad RCP setup
Jb: no fringes
Nt: R1 and R3 missing due to the dead tracks, see note above.
Ur,Sh: have no RCP receiver
Plots of the uncalibrated amplitude and phase against frequency
channel.
Comments.
Mc: bad RCP setup
Jb: no fringes
Nt: R1 and R3 missing due to the dead tracks, see note above. The bandpass was far from ideal.
The uncalibrated amplitude and phase of the crosshand
correlations against frequency channel.
Comments.
TSYS against time.
Comments.
Telescope sensitivities from the a priori TSYS and Gain
curves (the square of this number gives the antenna noise (SEFD) in Jy - the smaller the better).
Comments.
Jb: the MkII gaincurve was used in the pipeline by mistake.
On: in RCP was a bit less sensitive than expected (SEFD=600 Jy, see the EVN Status Tables).
Ur: less sensitive than expected (SEFD=365 Jy)
Hh: much less sensitive than expected (SEFD=700 Jy)
Fringe-fit phase solutions (including Parallactic Angle
correction).
Comments.
Fringe-fit delay solutions.
Comments.
Fringe-fit rate solutions.
Comments.
Telescope bandpasses.
Comments.
Bandpass edges were flagged. Nt had a dip in the middle of each channel.
Calibrated amplitude and phase against time
(a priori amplitude calibration and fringe-fit solutions applied).
Comments.
Calibrated amplitude and phase against frequency channel.
Comments.
Ur: channels 3L/4L had lower amplitude signal. These correspond to BBC3 lower and upper sidebands.
Nt: the bandpass was variable! It was good in 2020+121, 3C84 and DA193 scans - these were used for BPASS calibration. Other sources show uncalibrated bandpasses, which makes the calibration unreliable. Channels 1L/2L had lower amplitude signal. These correspond to BBC2 lower and upper sidebands.
Naturally weighted dirty map produced before self-cal of:
DA193.
3C84.
J0310+3814.
J0518+3306.
Comments.
Uniformly weighted dirty map produced before self-cal of:
DA193.
3C84.
J0310+3814.
J0518+3306.
Comments.
Phase corrections applied to a priori calibrated and fringe-fitted data by self-calibration.
Comments.
Amplitude corrections applied to a priori calibrated and fringe-fitted data by self-calibration.
Also available as a text file.
Comments.
Ur: sometimes had high corrections (a factor of 4 in Tsys), especially channels 3L/4L. See note on low amplitude from BBC3 above.
Sh: high corrections (a factor of 2-3 in Tsys)
Hh: high corrections (a factor of 2-3 in Tsys)
Nt: large corrections for 1L/2L (up to a factor of 3 in Tsys).
Telescope sensitivities (the total AMP gain applied during
both a priori and self calibration; the square of this number gives the antenna
noise (SEFD) in Jy).
Comments.
On: both LCP and RCP were a bit less sensitive than expected.
Ur: channels 3L/4L tended to be less sensitive than the others.
Sh: more sensitive than expected. The EVN Status Tables list SEFD=1120 Jy.
Hh: much less sensitive than expected (SEFD=700 Jy)
Nt: all channels were somewhat less sensitive than expected.
Residual closure phase (visibility closure phase with model closure phase subtracted) for:
DA193.
3C84.
J0310+3814.
J0518+3306.
Comments.
Calibrated visibilities and the source model of:
DA193.
3C84.
J0310+3814.
J0518+3306.
Comments.
Calibrated visibilities against u,v distance for:
DA193. postscript , png (smaller)
3C84. postscript , png (smaller)
J0310+3814. postscript , png (smaller)
J0518+3306. postscript , png (smaller)
Comments.
u,v coverage for:
DA193
postscript, png (smaller)
3C84
postscript, png (smaller)
J0310+3814
postscript, png (smaller)
J0518+3306
postscript, png (smaller)
Comments.
Crude map of DA193 from the pipeline.
Crude map of 3C84 from the pipeline.
Crude map of J0310+3814 from the pipeline.
Crude map of J0518+3306 from the pipeline.
Comments.