EVN Network Monitoring Experiment (NME) Pipeline Feedback


Pipeline feedback for experiment N08K2. If you have any comments on this experiment please email the address below.
A detailed description of the pipeline output is available.

Last updated: Fri Aug 15 15:23:32 CEST 2008 muehle@jive.nl

General Comments. ( Brief data summary and scan listing )
First fringes to Yebes 40-m!

K band (22 GHz) network monitoring experiment (NME) observed on 30 May 2008. The data rate was 256 Mbps (8 x 8 MHz subbands, dual polarization, two-bit sampling). The target sources 'J0916+3854' and 'J0923+3849' were calibrated using the phase-reference source '4C39.25'. '3C84' and '3C345' were also observed as calibrators. '4C39.25' served as fringe finder.
9 stations participated. This was the first time that the Yebes 40-m telescope participated in VLBI observations (position may still be a bit off). Ef recorded the data both on Mark5A (Ef) and Mark5B (Ef). At Jb, the MkII telescope (Jb2) was used for these observations. Cm transmitted signal in IFs 3 and 4 only, due to the limitations of its microwave link. Nt reported that the RCP was down for this session, which can be seen clearly in the extremely high T_sys of all RCP IFs.

The EVN reliability indicator (ERI) for this experiment was ERI = 0.98 . ERI* = 0.98 . (CM=1, EF=1, JB=1, ON=1, MC=1, NT=1, SH=1, MH=1, YS=0.92)

Plots of the autocorrelations
Comments.
Cm: limited bandpass, signal in IFs 3 and 4, check IF4/R; Eb: check IF 2/R+L, IF3/L, IF4/L; Nt: check IF1/R, IF4/L; 67 pages

plots of the uncalibrated amplitude and phase against time
Comments.
Ef: scan 30 bad; Sh: fast phase rotation, phases hard to follow; Nt: phases hard to follow in IF3/L, IF4/L out, all IFs/R noisy; Cm: very fast phases in IF3+4/L; 24 pages

Plots of the uncalibrated amplitude and phase against frequency channel
Comments.
Mc: bad phases in first scan; Nt: IF4/L out, IF3/L: at times noisy phases, low amplitude, all IFs/R: phases tend to be noisier; Sh: noisy phases, probably due to low S/N; 48 pages

The uncalibrated amplitude and phase of the crosshand correlations against frequency channel
Comments.
24 pages

TSYS against time
Comments.
dependence of T_sys on the elevation of the source clearly traceable; Ys, Cm, Jb: T_sys=1; Nt: extremely high T_sys (~10^5K) and jumps in RCP (all IFs); Sh: rapid fluctuations in IF2/L at 12:45 - 13:45; 8 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.
see comments for "TSYS against time"; 8 pages

Fringe-fit phase solutions (including Parallactic Angle correction).
Comments.
refant = Ef; as expected, generally fast phases; Ys: geographical position of the telescope may be a bit off; particularly fast phase rotation for Cm; Nt: IF3/L out ca. 12:30-16:00 UT; Sh: good solutions sparse in the first hour of observations; 7 pages

Fringe-fit delay solutions
Comments.
refant = Ef; delays of the order of nanoseconds or a few tens of nanoseconds; 7 pages

Fringe-fit rate solutions
Comments.
refant = Ef; rates of the order of mHz, a few tens of mHz for Cm; 7 pages

Telescope bandpasses
Comments.
refant = Ef; Nt: IF4/L out; Cm: large phases at edges of the subbands; 2 pages

Calibrated amplitude and phase against time (a priori amplitude calibration and fringe-fit solutions applied).
Comments.
refant = Ef; phases still show significant deviations from zero; Sh: low S/N on this baseline; Cm: IF3+4/L: noisy phases; Nt: IF3/L out after 12:30 UT; 16 pages

Calibrated amplitude and phase against frequency channel
Comments.
Nt: IF3+4/L missing after 12:30 UT; Sh: in the beginning, some IFs temporarily missing and phases noisy or bad, but continuously improving, ok after 13:47 UT; 46 pages

Naturally weighted dirty map (not useful for bright sources) produced before self-cal of:
3C345: pdf (not available) , or FITS (not available) .
3C84: pdf (not available) , or FITS (not available) .
4C39.25: pdf (not available) , or FITS (not available) .
J0916+3854: pdf , or FITS .
J0923+3849: pdf , or FITS .
Comments.

Uniformly weighted dirty map (not useful for bright sources) produced before self-cal of:
3C345: pdf (not available) , or FITS (not available) .
3C84: pdf (not available) , or FITS (not available) .
4C39.25: pdf (not available) , or FITS (not available) .
J0916+3854: pdf , or FITS .
J0923+3849: pdf , or FITS .
Comments.

Phase corrections applied to a priori calibrated and fringe-fitted data by self-calibration.
3C345 .
3C84 .
4C39.25 .
J0916+3854 (not available) .
J0923+3849 (not available) .
Comments.
refant = Ef; significant phase corrections for Ys and Cm; all other stations ok; 5-7 pages per source

Amplitude corrections applied to a priori calibrated and fringe-fitted data by self-calibration.
3C345: pdf , or text file , or statistical summary .
3C84: pdf , or text file , or statistical summary .
4C39.25: pdf , or text file , or statistical summary .
J0916+3854: pdf (not available) , or text file (not available) , or statistical summary (not available) .
J0923+3849: pdf (not available) , or text file (not available) , or statistical summary (not available) .
Comments.
significant gain corrections for Cm and Sh; On: significant slope in the corrections over time; 5-7 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.
7 pages

Residual closure phase (visibility closure phase with model closure phase subtracted) for:
3C345 .
3C84 .
4C39.25 .
J0916+3854 (not available) .
J0923+3849 (not available) .
Comments.
closure phases including Nt noisier than usual; loops that include Sh (i.e. longest baselines) show large spread; up to 12 pages per source

Calibrated visibilities and the source model of:
3C345 .
3C84 .
4C39.25 .
J0916+3854 (not available) .
J0923+3849 (not available) .
Comments.
Ys: significant deviations from the model (but not bad for the first VLBI observations ever!); Cm: significant deviations from the model; Mc: deviations in LCP during the last 30 minutes of 4C39.25; Mh: deviations at around 12:50 UT; up to 16 pages per source

Calibrated visibilities against u,v distance for:
3C345: pdf , or png .
3C84: pdf , or png .
4C39.25: pdf , or png .
J0916+3854: pdf , or png .
J0923+3849: pdf , or png .
Comments.

u,v coverage for:
3C345: pdf , or png .
3C84: pdf , or png .
4C39.25: pdf , or png .
J0916+3854: pdf , or png .
J0923+3849: pdf , or png .
Comments.

Crude maps of sources:
3C345: pdf , or FITS .
3C84: pdf , or FITS .
4C39.25: pdf , or FITS .
J0916+3854: pdf , or FITS .
J0923+3849: pdf , or FITS .
Comments.