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Pipeline feedback for experiment EP037A_2.
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Last updated: Thu Jul 3 14:53:38 CEST 2003
imai@jive.nl
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General Comments.
(
Brief data summary and
scan listing.)
This project consists of 6 telescopes: Jb, Eb, Nt, On, Tr, Hh. Only LCP was valid in Hh. Very high Tsys in LCP in Eb.
There are two passes, 1st for line sources (IF1), 2nd for continuum sources (IF1-4). This page is for the 2nd pass.
Used 2-MHz 1 bands x 2 pols, with 2-bits sampling. Obtained 2 pairs of polarization (LL, RR) in 2-sec integration. 64 spectral channels per IF.
Eb is a reference antenna (Jb is a plot-reference antenna).
Phase-reference sources were not detected in each of IFs and Pols. ERI=0.08(Jb=0.15, Eb=0.23, Nt=0.19, On=0.20, Tr=0.19, Hh=0.06, Only LCP availablity and elevation limit in Hh is taken into account. Only 25% of the data were remained after fring fittitng). ERI*=0.50 (Jb*=0.60, Eb*=0.93, Nt*=0.75, On*=0.79, Tr*=0.77, Hh*=0.17, lost scans due to the limit of antenna-slewing speeds and no detection of phase-reference continuum sources are taken into account).
Plots of the autocorrelations.
Comments.
Jb: Dead in IF2 Rpol.
Bb: Negative amplitude in IF3&4 in Lpol and IF4 in Rpol.
Nt: No data in 17:39-18:02 in Lpol.
On: No data in 14:38-15:01, a bright spur in IF1 L&Rpols.
Tr: A bright spur in IF1&2 L&Rpols.
Hh: A weak and wide spur in IF1&2 Lpol.
Plots of the uncalibrated amplitude and phase against time.
Comments.
Bright calibrators, observed every 30 min, were detected.
Eb: RR had very poor sensitivity.
Nt: Data lost 16:15-16:30, 17:05-18:05, 00:25-01:00, 04:00-04:20.
On: Data lost 13:40-14:00, 14:20-15:05, 20:20-21:00, 21:30-23:20.
Tr: Data lost 04:30-05:00.
Plots of the uncalibrated amplitude and phase against frequency
channel.
Comments.
J2052+3635 was also detected.
Nt: Dead in IF4 Lpol 13:48-13:50.
Tr: Occasionally bright spur in IF1&2 L&Rpols. Dead in IF4 Lpol 13:48-13:50, IF2&4 R&Lpols 05:28-05:30, 05:48-05:55, IF1-4 Rpol 05:40-05:42.
The uncalibrated amplitude and phase of the crosshand
correlations against frequency channel.
Comments.
No data.
TSYS against time.
Comments.
Eb: Tsys=700-900 K in Rpol, Tsys=700 K at 21:05 in Lpol.
Hh: Up to 250 K at 22:10-22:20.
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, On: Roughly consistent with that in EVN status table.
Eb: Roughly consistent with and 500% of that in EVN status table in Lpol and Rpol, respectively.
Nt: SEFD=900-1600 Jy.
Tr: About 140% of that in EVN status table.
Hh: About 140% of that in EVN status table.
Fringe-fit phase solutions.
Comments.
Solutions were almost lost from the phase-reference calibrators.
Eb (reference): Phase slope due to parallactic angle correction. Solutions lost 19:00-23:00 in IF4 RR.
Jb: Solutions lost 17:00-23:00 in RR.
Nt: Solutions lost 12:30-16:40 in RR (also 17:00-23:10 in IF4), 14:30_15:40 in LL.
On: Solutions lost 13:10-14:00, 21:40-23:00 in RR&LL.
Tr: Solutions lost 19:00-00:60 in IF4 RR, 05:00-06:00 in LL.
Hh: Solutions lost 12:30-23:00 in LL.
Fringe-fit delay solutions.
Comments.
Jb: Offsets about 30 nsec in average, with wrap within 50 nsec.
Nt: Offsets up to 800 nsec in IF2 RR, 120 nsec in IF3 RR.
On: Systematic offset change with time within 40 nsec.
Tr: Offsets about 50 nsec in average.
Hh: Offsets about 40 nsec in average.
Fringe-fit rate solutions.
Comments.
Rate offsets within 2 mHz, sometimes up to 6 mHz.
Telescope bandpasses.
Comments.
Bandpass amplitudes and phases were well determined,
Calibrated amplitude and phase against time
(a priori amplitude calibration and fringe-fit solutions applied).
Comments.
Large phase drifts were well reduced. Occasionally phase wrap still remains.
Calibrated amplitude and phase against frequency channel.
Comments.
Phase gradients along frequency were removed. But phase offsets and and amplitude slopes still occasionally remain.
Phase corrections applied to a priori calibrated and fringe-fitted data by self-calibration.
Comments.
Phase solutions determind in each scan of above 4 calibrators.
Naturally weighted dirty map produced before self-cal of:
J0555+3948.
J1642+3948.
J2025+3343.
J2136+0041.
Comments.
Plots for J0603+2159, J1946+2300, J2012+4628 and J2052+3635 are unavailable.
J0555+3948: Appears over 3rd contour (0.77 Jy/beam).
J1642+3948: Fringe pattern appears over 3rd contour (1.6 Jy/beam).
J2025+3343: Appears over 3rd contour (0.44 Jy/beam).
J2136+0041: Fringe pattern appears over 2nd contour (0.83 Jy/beam).
Uniformly weighted dirty map produced before self-cal of:
J0555+3948.
J1642+3948.
J2025+3343.
J2136+0041.
Comments.
Plots for J0603+2159, J1946+2300, J2012+4628 and J2052+3635 are unavailable.
J0555+3948: Appears over 2nd contour (0.80 Jy/beam).
J1642+3948: Fringe pattern appears over 3rd contour (2.3 Jy/beam).
J2025+3343: Appears over 2nd contour (0.26 Jy/beam).
J2136+0041: Fringe pattern appears over 3rd contour (1.9 Jy/beam).
Amplitude corrections applied to a priori calibrated and fringe-fitted data by self-calibration.
Also available as a text file.
Comments.
Gain correction factors usually within 1.5. Solutions were lost for J2052+3635.
Jb: Gain correction factors occasionally up to 5.0.
. Tr: Gain correction factors occasionally up to 4.0 and down to 0.4.
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.
Jb: 10-40% of that in EVN status table.
Eb: 70-130% in Lpol and 400-1000% in Rpol of that in EVN status table.
Nt: SEFD=400-1200 Jy.
On: 40-100% of that in EVN status table.
Hh: 100-400% of that in EVN status table.
Residual closure phase (visibility closure phase with model closure phase subtracted) for:
J0555+3948.
J1642+3948.
J2025+3343.
J2136+0041.
Comments.
J0555+3948: Closure phase offset within 50 degrees.
J1642+3948: Closure phase offset within 20 degrees.
J2025+3343: Roughly zero closure phases.
J2136+0041: Closure phase offset within 50 degrees.
Calibrated visibilities and the source model of:
J0555+3948.
J1642+3948.
J2025+3343.
J2136+0041.
Comments.
J0555+3948: A source model consistent with observed phases, but inconsistent with observed amplitudes in LL.
J1642+3948: A source model consistent with observed phases, partially consistent with amplitudes of the model.
J2025+3343: A source model roughly consistent with observed amplitudes and phases.
J2136+0041: Occasionally a source model is inconsistent with observed amplitudes and phases.
Calibrated visibilities against u,v distance for:
J0555+3948. postscript , png (smaller)
J1642+3948. postscript , png (smaller)
J2025+3343. postscript , png (smaller)
J2136+0041. postscript , png (smaller)
Comments.
J0555+3948: Roughly constant around 1.5 Jy.
J1642+3948: Roughly constant around 4 Jy, sparse distribution.
J2025+3343: Roughly constant around 0.3 Jy.
J2136+0041: About 5 Jy at 20M lambda, about 1.5 Jy at 190M lambda.
u,v coverage for:
J0555+3948
postscript, png (smaller)
J1642+3948
postscript, png (smaller)
J2025+3343
postscript, png (smaller)
J2136+0041
postscript, png (smaller)
Comments.
J0555+3948, J1642+3948, J2136+0041: Elongated in the north-south direction up to 180M lambda.
J2025+3343: Slightly elongated in the north-south direction up to 50M lambda.
Crude map of J0555+3948 from the pipeline.
Crude map of J1642+3948 from the pipeline.
Crude map of J2025+3343 from the pipeline.
Crude map of J2136+0041 from the pipeline.
Comments.
J0555+3948: An unresolved core and several side lobes.
J1642+3948: An unresolved core and several side lobes.
J2025+3343: An unresolved core and bright side lobes.
J2136+0041: Emission out of the map field.