EVN Network Monitoring Experiment (NME) Pipeline Feedback


Pipeline feedback for experiment N08Q1. 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 Mar 24 15:50:09 CET 2009 muehle@jive.nl

General Comments. ( Brief data summary and scan listing )
Q band network monitoring experiment (NME) observed on 16 October 2008. The data rate was 256 Mbps (8 x 8 MHz subbands, dual polarization, two-bit sampling). The experiment consisted of long scans on calibrator sources from various catalogs that were selected for likely being strong at 43 GHz: '1749+096', '1633+382', '1741-038', and '2200+420' as well as the VLBA fringe finders '3C345', 'J1800+3848', '2013+370' and '3C454.3'. The maser sources 'RCas' and 'UHer' were observed to provide additional diagnostics to the stations during the observations. '3C345' served as fringe finder. In the pipeline, Ef was the reference antenna (On, when Ef not available) and solint was set to 0.5 min.
3 stations participated: Ef, On, Nt. Ef skipped a few scans for pointing. It was raining in Ef at the beginning of the experiment, but it cleared up later. At On, there was rain during the last hour(s).

The EVN reliability indicator (ERI) for this experiment was ERI = 1.0 . ERI* = 1.0 . (EF=1, ON=1, NT=1)

Plots of the autocorrelations
Comments.
stable bandpasses; Nt: large gradient in IF1/R, other bandpasses wiggly, but flat; Ef: ripples in bandpass when observing the maser line (U Her, IF1); 12 pages

plots of the uncalibrated amplitude and phase against time
Comments.
as expected, very fast phases; 8 pages

Plots of the uncalibrated amplitude and phase against frequency channel
Comments.
even uncalibrated, phases look good for the strongest sources; maser line of U Her detected (IF1); 12 pages

The uncalibrated amplitude and phase of the crosshand correlations against frequency channel
Comments.
even uncalibrated, phases look good for the strongest sources and most sensitive baselines; 12 pages

TSYS against time
Comments.
system temperature clearly increased at low source elevations, e.g. for 3C454.3; On: unusually high T_sys in all subbands at 14:45-15:00 UT (rain in line of sight?); 3 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.
very good match to T_sys vs. time (see above); 3 pages

Fringe-fit phase solutions (including Parallactic Angle correction).
Comments.
refant = Ef; as expected, very fast phases; few or no solutions for J1800+38, U Her (IF1 only), 1741-038, 2200+420, R Cas; 3 pages

Fringe-fit delay solutions
Comments.
refant = Ef; delays of the order of a few tens of nanoseconds; 3 pages

Fringe-fit rate solutions
Comments.
refant = Ef; rates of the order of tens of mHz; significant deviations at ~13:20 UT; 3 pages

Telescope bandpasses
Comments.
refant = Ef; amplitudes and phases well aligned; 1 page

Calibrated amplitude and phase against time (a priori amplitude calibration and fringe-fit solutions applied).
Comments.
phases much improved with the pipeline calibration process, but not surprisingly, still noisier than those at lower frequencies; careful flagging of the data necessary (e.g. at ~14:20 UT); amplitude of 3C454.3 in last scans significantly higher than in earlier scans = source elevation effect?; 8 pages

Calibrated amplitude and phase against frequency channel
Comments.
phases best constrained for the strongest sources; little or no data on J1800+38, U Her, 1741-038, 2200+420, R Cas (see above); 10 pages

Naturally weighted dirty map (not useful for bright sources) produced before self-cal of:
1749+096: pdf (not available) , or FITS (not available) .
3C345: pdf (not available) , or FITS (not available) .
2013+370: pdf (not available) , or FITS (not available) .
1633+382: pdf (not available) , or FITS (not available) .
3C454.3: pdf (not available) , or FITS (not available) .
Comments.

Uniformly weighted dirty map (not useful for bright sources) produced before self-cal of:
1749+096: pdf (not available) , or FITS (not available) .
3C345: pdf (not available) , or FITS (not available) .
2013+370: pdf (not available) , or FITS (not available) .
1633+382: pdf (not available) , or FITS (not available) .
3C454.3: pdf (not available) , or FITS (not available) .
Comments.

Phase corrections applied to a priori calibrated and fringe-fitted data by self-calibration.
1749+096 .
3C345 .
2013+370 .
1633+382 .
3C454.3 .
Comments.
refant = Ef; phase corrections resonable for Q-band data; 3 pages per source

Amplitude corrections applied to a priori calibrated and fringe-fitted data by self-calibration.
1749+096: pdf (not available) , or text file (not available) , or statistical summary (not available) .
3C345: pdf (not available) , or text file (not available) , or statistical summary (not available) .
2013+370: pdf (not available) , or text file (not available) , or statistical summary (not available) .
1633+382: pdf (not available) , or text file (not available) , or statistical summary (not available) .
3C454.3: pdf (not available) , or text file (not available) , or statistical summary (not available) .
Comments.
only phases self-calibrated

Telescope sensitivities (not available) (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.
self-calibration on phases only; for telescope sensitivies, please refer to GB060B

Residual closure phase (visibility closure phase with model closure phase subtracted) for:
1749+096 .
3C345 .
2013+370 .
1633+382 .
3C454.3 .
Comments.
in general, residual closure phases small; few outliers; 1 page per source

Calibrated visibilities and the source model of:
1749+096 .
3C345 .
2013+370 .
1633+382 .
3C454.3 .
Comments.
except for short-scale phase fluctuations, generally good agreement between data and model; careful inspection and flagging of the data , e.g. 1749+096 at 14:16-14:18 UT, should improve agreement significantly; 8 pages per source

Calibrated visibilities against u,v distance for:
1749+096: pdf , or png .
3C345: pdf , or png .
2013+370: pdf , or png .
1633+382: pdf , or png .
3C454.3: pdf , or png .
Comments.

u,v coverage for:
1749+096: pdf , or png .
3C345: pdf , or png .
2013+370: pdf , or png .
1633+382: pdf , or png .
3C454.3: pdf , or png .
Comments.

Crude maps of sources:
1749+096: pdf , or FITS .
3C345: pdf , or FITS .
2013+370: pdf , or FITS .
1633+382: pdf , or FITS .
3C454.3: pdf , or FITS .
Comments.
all listed sources detected