EVN Network Monitoring Experiment (NME) Pipeline Feedback


Pipeline feedback for experiment N10K1. If you have any comments on this experiment please email the address below.
A detailed description of the pipeline output is available.

Last updated: Tue Feb 1 19:27:44 CET 2011 muehle@jive.nl

General Comments. ( Brief data summary and scan listing )
K band (22 GHz) network monitoring experiment (NME) observed on 29 October 2010. The test focussed on the low-frequency part of the band at ~22.01 GHz. The data rate was 512 Mbps (4 x 16 MHz subbands, dual polarization, two-bit sampling). The experiment consisted of long scans on the calibrator sources '3C273', '3C345, '3C454.3', and '4C39.25' and a fast-phase referencing part with 'NRAO512' as the target and '3C345' as the phase reference. In this pipeline reduction, Ef, Mc and On served as reference antennas and Ef was the plot reference, i.e. baselines to Ef are plotted. The pipeline used the fully patched AIPS version 31DEC09 and a solution interval of 0.5 min.
7 stations participated in the experiment: Cm, Ef, Jb, On, Mc, Mh and Ys. There were fringes to all stations in all channels, except for IF1 of Mh (see NME report for details). As a consequence, IF1 of Mh has been flagged for the entire experiment before the pipeline was run. The data of Cm transmitted via the microwave link are in IF1 and parts of IF2. In order to properly calibrate IF2, the channels without valid data in IF2 have been flagged. IF3 and IF4 of Cm have been flagged as well. At Jb, BBC03 (= IF2/L) had no power at the start of the experiment and was exchanged at 13:14 UT. Jb had to stop observing at ~14:30 UT due to strong gusts of wind, shortly after an exchange of the disk pack (14:22 - 14:28 UT). Ys started observing with an incorrect tuning, but fixed the bug by 12:53 UT, and went into windstop shortly after the end of the experiment at 15:00 UT.

The EVN reliability indicator (ERI) for this experiment was ERI = 0.79 . ERI* = 0.84 . (CM=1, EF=1, JB=0.83, ON=1, MC=1, MH=0.75, YS=0.71)

Plots of the autocorrelations
Comments.
bandpasses seem to be stable; Cm: IF3, IF4 and upper half of IF2 flagged (no signal); Mh: IF1 flagged, wiggely, but stable bandpasses in LCP channels; Jb: bandpasses in RCP channels show a strong deterioration after ~14:30 UT; 62 pages

plots of the uncalibrated amplitude and phase against time
Comments.
not unexpectedly, fast phase rotation seen on all baselines; in general, phases can be followed easily; Jb: strong deterioration after ~14:30 UT, IF2/L bad until 13:14 UT (see comments above); Ys: wrong tuning until 12:53 UT; 16 pages

Plots of the uncalibrated amplitude and phase against frequency channel
Comments.
except for the glitches already mentioned, bandpasses seem to be stable; even uncalibrated, phases can easily be followed on all baselines; 61 pages

The uncalibrated amplitude and phase of the crosshand correlations against frequency channel
Comments.
looking good; in strong sources, even the uncalibrated phases can easily be followed on all baselines; 31 pages

TSYS against time
Comments.
Cm, Jb: no Tsys information available; On: Tsys include the atmosphere (chopper-wheel calibration); Ys: no Tsys information available; 6 pages

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.
mimic curves of Tsys; 6 pages

Fringe-fit phase solutions (including Parallactic Angle correction).
Comments.
refant = Ef, drift in phases reflects the parallactic angle correction; generally fast fringe rates, especially for Cm; Ys: wrong tuning until 12:53 UT; 5 pages

Fringe-fit delay solutions
Comments.
refant = Ef; delays of the order of (a few tens of) nanoseconds, larger for Cm; a few outliers at Jb and Ys; 5 pages

Fringe-fit rate solutions
Comments.
refant = Ef; rates of the order of mHz, a bit larger for Jb (< 20 mHz), Ys (< 20 mHz) and Cm (< 50 mHz); 5 pages

Telescope bandpasses
Comments.
refant = Ef; in general, amplitudes close to 1.0 and phases close to zero, except at the edges of the bandpasses; Mh: prominent kink in bandpass and large phases in IF4/R; 2 pages

Calibrated amplitude and phase against time (a priori amplitude calibration and fringe-fit solutions applied).
Comments.
except for a few glitches at individual stations, stable amplitudes and phases; phases aligned close to zero, except for Cm; noise level seems to be higher during the last 30 min of the experiment; 16 pages

Calibrated amplitude and phase against frequency channel
Comments.
in general, amplitudes look ok; phases close to zero for the calibrators, a bit larger for Cm; 62 pages

Naturally weighted dirty map (not useful for bright sources) produced before self-cal of:
3C273: pdf (not available) , or FITS (not available) .
3C345: pdf (not available) , or FITS (not available) .
3C454.3: pdf (not available) , or FITS (not available) .
NRAO512: pdf , or FITS .
4C39.25: pdf (not available) , or FITS (not available) .
Comments.

Uniformly weighted dirty map (not useful for bright sources) produced before self-cal of:
3C273: pdf (not available) , or FITS (not available) .
3C345: pdf (not available) , or FITS (not available) .
3C454.3: pdf (not available) , or FITS (not available) .
NRAO512: pdf , or FITS .
4C39.25: pdf (not available) , or FITS (not available) .
Comments.

Phase corrections applied to a priori calibrated and fringe-fitted data by self-calibration.
3C273 .
3C345 .
3C454.3 .
NRAO512 (not available) .
4C39.25 .
Comments.
refant = Ef; generally, phase corrections of the order of degrees (< 20 deg), a bit larger for Cm; a few outliers; Jb: few solutions found for 3C454.3 (windstop); 5 pages per source

Amplitude corrections applied to a priori calibrated and fringe-fitted data by self-calibration.
3C273: pdf , or text file , or statistical summary .
3C345: pdf , or text file , or statistical summary .
3C454.3: pdf , or text file , or statistical summary .
NRAO512: pdf (not available) , or text file (not available) , or statistical summary (not available) .
4C39.25: pdf , or text file , or statistical summary .
Comments.
note that the pipeline does not correct for atmospheric opacity at those stations that provide opacity-free gain curves (Ef, On, Mc); Cm, Jb, Ys: no Tsys information available, thus correction factors may deviate significantly from 1; Jb: few solutions found for 3C454.3 (windstop); Cm: IF1/L and IF2/L tend to have a small correction factor, IF2/R a large one; a few outliers; 5 pages per source

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.
nothing unusual detected; a few outliers; 5 pages

Residual closure phase (visibility closure phase with model closure phase subtracted) for:
3C273 .
3C345 .
3C454.3 .
NRAO512 (not available) .
4C39.25 .
Comments.
residual closure phases generally clustered around a small value; a few outliers; 4-7 pages per source

Calibrated visibilities and the source model of:
3C273 .
3C345 .
3C454.3 .
NRAO512 (not available) .
4C39.25 .
Comments.
in general, very good agreement between models and data; a few outliers and deviations, possibly due to missing opacity correction; 10-16 pages per source;

Calibrated visibilities against u,v distance for:
3C273: pdf , or png .
3C345: pdf , or png .
3C454.3: pdf , or png .
NRAO512: pdf , or png .
4C39.25: pdf , or png .
Comments.

u,v coverage for:
3C273: pdf , or png .
3C345: pdf , or png .
3C454.3: pdf , or png .
NRAO512: pdf , or png .
4C39.25: pdf , or png .
Comments.

Crude maps of sources:
3C273: pdf , or FITS .
3C345: pdf , or FITS .
3C454.3: pdf , or FITS .
NRAO512: pdf , or FITS .
4C39.25: pdf , or FITS .
Comments.