EVN User Experiment Pipeline Feedback


Pipeline feedback for experiment GB060A. If you have any comments on this experiment please email the address below.
A detailed description of the pipeline output is available.

Last updated: Thu Apr 24 19:34:19 CEST 2008 muehle@jive.nl

General Comments. ( Brief data summary and scan listing )
7mm global VLBI experiment, observed on 23 October 2007. The data rate was 512 Mbps (8 X 16 MHz subbands, dual polarization, two-bit sampling). The target source was 'CYG-A'. '3C345', '1749+096', '2013+370', and 'BLLAC' were also observed as calibrators. '1749+096' and 'BLLAC' serve as polarization calibrators. '1749+096' was also the bandpass calibrator. The solint was 4 min. Gb served as reference antenna. The plots show baselines to either Ef or Gb.
9 VLBA and 3 EVN stations participated. In addition, one VLA antenna and the GBT participated. A detailed description of the antenna performances can be found in the PI letter. Please note that the scan numbers given below refer to the numbering in the observed schedule (see for example Standardplots/gb060a.sum), not to the scan listing given on this page.

The EVN reliability indicator (ERI) for this experiment was ERI = 0.29 . ERI* = 0.29 . (EF=0.91, ON=1.0, NT=0)

Plots of the autocorrelations
Comments.
no RFI detected; YY: curvy, but stable bandpasses; NT: noisy bandpasses, NT/scan 2: spikes in RR/IF1+3, NT/scan 45: strong ringing in RR/IF2;195 pages

plots of the uncalibrated amplitude and phase against time
Comments.
constant amplitudes except for GB/IF4 LL and RR (scan 27) and GB/IF3 LL and RR; KP: IF4/RR missing at ~17:00 - 01:30; YY: phases hard to follow; on short baselines (e.g. EF-ON), phases can be followed even in CYG-A; 54 pages

Plots of the uncalibrated amplitude and phase against frequency channel
Comments.
NT: as expected, phases can't be followed; YY: phases can't be followed in calibrators until 02:17 (= scans up to 71), probably because of subreflector error; in scans 24 and 72, IF3+4/RR and LL ok; in the following scans (73-117), IF2/RR noisy; KP: IF4/RR missing at 17:06 - 02:24; a few baselines show noisy phases in individual scans, e.g. GB-KP/scan 4, GB-FD/scan 9, GB-OV/scan 14, 20, GB-PT/scan 18; fast phase rates in a few scan/IF combinations: FD/IF3/RR (scans 33, 36, 50, 60, 69, 70), MK/IF1/RR (scan 44), KP/IF4/RR (scan 57, 69, 70), HN/IF4/RR (scans 78, 82, 84, 87), LA/IF3/RR (scan 84), ON/IF1/RR (scan 84); in the last hour, phases in calibrator scans (100-117) noisy, probably because of low source elevation; 255 pages

The uncalibrated amplitude and phase of the crosshand correlations against frequency channel
Comments.
phases of polarized calibrators can be followed on many baselines; GB-KP/IF4 missing at 17:06 - 02:24; HN/IF4 missing in scan 4; fast phase rates noticable in a few scan/IFs: FD/IF3 (scan 33), HN/IF4 (scan 82); EF/IF1 bad spikes in bandpass at 17:06 - 17:27 (scan 6/7); 145 pages

TSYS against time
Comments.
GB: T_sys rising after ~04:00, probably due to weather; HN: sharp increase of T_sys to ~300K at ~01:00 due to rain; OV: high T_sys (> 300K) from start until ~19:10, then jump to ~150K; MK: apparently constant T_sys at 20:04 - 21:07 because of interpolation between first and second scan, high T_sys at start of observations, probably due to very low source elevation; ON: T_sys steadily increasing, due to weather/elevation effects? NT: T_sys infrequently measured for RCP, very high values (up to 30,000K!); 12 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.
GB: gain amplitude rising after ~04:00, probably due to weather; at ~19:10 jump in gain (OV) and outliers at other VLBA stations and YY; at ~3:10, outlier at HN and NL; NT: only sparse gain information available; 12 pages

Fringe-fit phase solutions (including Parallactic Angle correction).
Comments.
refant = Gb; as expected, very fast phases; GB: phase changes from ~100 deg to ~300 at 23:00-00:00 YY: few good SN before ~02:10; KP: no good SN for IF4/R at ca. 17:00 - 02:00; 11 pages

Fringe-fit delay solutions
Comments.
nothing unexpected detected, delays of the order of (tens of) nanoseconds in an individual IF; few outliers, mostly in IF3/R at 23:00-00:00, also FD/IF3/R 21:00-02:10; LA/IF3/R 05:00-06:00; YY: very few good SN before ~02:10; KP: no good SN for IF4/R at ca. 17:00 - 02:10; 11 pages

Fringe-fit rate solutions
Comments.
nothing unexpected detected; GB:(= refant) few good SN during the last 2 hours (low source elevation); YY: very few good SN before ~02:10; KP: no good SN for IF4/R at ca. 17:00 - 02:10; 11 pages

Telescope bandpasses
Comments.
nothing unexpected detected; YY: curvy bandpasses, slightly larger phases; EF, ON: significant slope in bandpasses; 3 pages

Calibrated amplitude and phase against time (a priori amplitude calibration and fringe-fit solutions applied).
Comments.
not surprisingly, the phases at this stage of the calibration process are noisier than usual at lower frequencies, data require careful flagging and a calibration strategy that is beyond the scope of the pipeline; 48 pages

Calibrated amplitude and phase against frequency channel
Comments.
as expected, phases best constrained in the strongest soures (1749+096, BL Lac and 2013+37) at high elevation (20:00-04:30) and on short baselines; KP: amplitude in IF2/R and IF4/R continuously low or missing; YY: from ~2:30, amplitude in IF2/R continuously low in addition, instances of individual stations/IFs/scans showing low amplitudes and/or noisy/fast phases. e.g. FD/IF3/R in scans 44, 50, 54, 69, 72; 224 pages

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

Phase corrections applied to a priori calibrated and fringe-fitted data by self-calibration.
1749+096 .
2013+370 .
3C345 .
BLLAC .
CYG-A .
Comments.
large corrections; 11 pages per source

Amplitude corrections applied to a priori calibrated and fringe-fitted data by self-calibration.
1749+096: pdf , or text file , or statistical summary .
2013+370: pdf , or text file , or statistical summary .
3C345: pdf , or text file , or statistical summary .
BLLAC: pdf , or text file , or statistical summary .
CYG-A: pdf , or text file , or statistical summary .
Comments.
11 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 unexpected detected; 11 pages

Residual closure phase (visibility closure phase with model closure phase subtracted) for:
1749+096 .
2013+370 .
3C345 .
BLLAC .
CYG-A .
Comments.
nothing unexpected detected, small residual closure phases for the calibrators; ca. 52 pages per source

Calibrated visibilities and the source model of:
1749+096 .
2013+370 .
3C345 .
BLLAC .
CYG-A .
Comments.
nothing unexpected detected; ca. 48 pages per source

Calibrated visibilities against u,v distance for:
1749+096: pdf , or png .
2013+370: pdf , or png .
3C345: pdf , or png .
BLLAC: pdf , or png .
CYG-A: pdf , or png .
Comments.

u,v coverage for:
1749+096: pdf , or png .
2013+370: pdf , or png .
3C345: pdf , or png .
BLLAC: pdf , or png .
CYG-A: pdf , or png .
Comments.

Crude maps of sources:
1749+096: pdf , or FITS .
2013+370: pdf , or FITS .
3C345: pdf , or FITS .
BLLAC: pdf , or FITS .
CYG-A: pdf , or FITS .
Comments.
all sources detected