EVN User Experiment Pipeline Feedback
Pipeline feedback for experiment EV012B.
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Last updated: Thu Oct 17 13:27:16 CEST 2002
imai@jive.nl
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General Comments.
(
Brief data summary and
scan listing.)
This project consists of 5 stations: Ef, Mc, Jb, Tr, Cm (On did not observe). Used 2-MHz 1 bands x 2 Pols. with 2-bits sampling. 1024 spectral channels per IF. Ef is a reference antenna.
On: did not observe because of strong wind.
Due to antenna slewing time, small parts of data were flagged.
ERI=0.61 (Ef=0.99, Mc=0.97, Jb=0.93, Tr=0.95, Cm=0.97, On=0.00) ERI*=0.92 (excluding On).
Plots of the autocorrelations.
Comments.
All antennas: a broad spur in L&R at 17:20-17:42 (observing the maser line?). Jb: a spur in Lpol at 11:57-12:19.
Cm: Radio-link signals, and occasionally a spur at middle of IF Lpol.
Tr. Occasionally a spur in Rpol.
Plots of the uncalibrated amplitude and phase against time.
Comments.
Calibrators are detected, except at 17:20-17:42.
Cm: fast phase variation.
Plots of the uncalibrated amplitude and phase against frequency
channel.
Comments.
Line (probably maser emission) found at 17:20-17:41. However, according to the scan table, this time range should be for scans towards the calibrators.
Cm: small phase gradients along frequency. Not detected at 12:58-13:04.
Jb: Not detected at 12:58-13:04.
The uncalibrated amplitude and phase of the crosshand
correlations against frequency channel.
Comments.
No data.
TSYS against time.
Comments.
Mc, Jb: sparse data points.
Tr: Cm: No observed value is recorded.
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.
Ef: About 50-60% of that in EVN status table.
Mc: oughly consistent with that in EVN status table.
Jb, Cm: Too high gain factors because assuming =0.001.
Tr: About 60% of that in EVN status table.
Fringe-fit phase solutions.
Comments.
Solutions with rapid phase dirifts, especially at Cm. Solutions are found at 17:20-17:41, therefore the calibrators were correctly observed and the maser emission was also likely to be observed in small duration.
Fringe-fit delay solutions.
Comments.
Offsets usually within 10 nsec, sometimes up to 50 nsec.
Fringe-fit rate solutions.
Comments.
Rates are within 2 mHz, except for Cm up to 10 mHz.
Telescope bandpasses.
Comments.
Amplitude & Phase characteristics well determined.
Calibrated amplitude and phase against time
(a priori amplitude calibration and fringe-fit solutions applied).
Comments.
Phase wrap still appears ocassionally.
Calibrated amplitude and phase against frequency channel.
Comments.
Banspass is well calibrated. Spurs are flagged out.
Phase corrections applied to a priori calibrated and fringe-fitted data by self-calibration.
Comments.
No comment.
Amplitude corrections applied to a priori calibrated and fringe-fitted data by self-calibration.
Also available as a text file.
Comments.
17:20-17:41: very high gain factors.
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.
Abnormally high gain factors at 12:30-13:00, 17:20-17:40. Difficult to precisely evaluate sensitivities from the plots.
Jb: SEFD< 900 Jy, Cm: SEFD< 1600 Jy.
Residual closure phase (visibility closure phase with
model closure phase subtracted) for J2022+61.
Residual closure phase (visibility closure phase with
model closure phase subtracted) for J2202+42.
Comments.
Almost constant closure phases.
Calibrated visibilities and the source model of
J2022+61.
Calibrated visibilities and the source model of
J2202+42.
Comments.
Sometimes models are inconsistent with observed amplitudes and phases.
On: IF2 RR data lost.
Calibrated visibilities against u,v distance for
J2022+61.
Calibrated visibilities against u,v distance for
J2202+42.
Comments.
All sources are detected in the longest baselines.
u,v coverage for
J2022+61.
u,v coverage for
J2202+42.
Comments.
Uniformly distributed within 30M lambda.
Crude map of J2022+61 from the pipeline.
Crude map of J2202+42 from the pipeline.
Comments.
J2022+61: A core and a structure elongated in the NE-SW direction.
J2202+42: An unresolved core and bright side lobes.