GENERAL
EB072. K-band experiment observed on 11 March 2019.
This is a spectral line pass dataset.
The data rate was 128 Mbps (1 x 16 MHz subbands, full polarization, two-bit sampling)
The target sources J0854+2006, J0319+4130, J0555+3948, J0359+5057, and J1229+0203 were directly fringe-fitted.
18 stations participated: Jb, Ef, Mc, Nt, O6, T6, Ur, Tr, Ys, Hh, Sv, Zc, Bd, Sr, Mh, Kt, Ky, Ku.
The following are plots from the EVN pipeline analysis, in which the reference antenna was: Ef.
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POSSM_AUTOCORR
Auto-corr amplitude vs frequency plots for each station showing all IFs and Pols.
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VPLOT_UNCAL
Amplitude and phase vs time, for the whole experiment, no calibration applied. Shows visibilities on all baselines to the reference antenna. All IFs and Pols shown. This is a good place to look for stations that missed scans during the experiment.
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POSSM_UNCAL
Uncalibrated, vector averaged, cross power specra for baselines to the reference antenna. No bandpass calibration applied yet. This is a good place to check how well detected sources are on each baseline.
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POSSM_CPOL
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TSYS
Plots of system temperature vs time for each station (and each IF). Flat-line plots indicate that this information was not available for a given station, in which case we create a generic Tsys table scaled to the station's gain (Jy/K). This information is stored in the TY1 table.
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GAIN
Gain info in CL2, determined using Tsys tables. Plot shows Gain vs time for each station, each IF and each Pol.
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FRING_PHAS
Plot of CL3. This is the CL table generated using CL2 (amplitude cal) and SN2 (FRING solutions). Plot shows phase calibration data vs time. Missing data indicate possible issues in those previous steps. If no issues arose, then use this table to phase-reference the target.
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FRING_DELAY
Plot of SN2. Shows delay vs time from FRING results (usually only calibrators and reference sources). This is a good place to look for times where FRING failed to get solutions. Here, FRING uses a signal to noise cutoff of 5. This is the spectral line pass data. Better solutions are expected in the continuum data.
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FRING_RATE
SN2 as above, but for rate.
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BANDPASS
Plot of BP1. Shows the bandpass characteristics of each antenna, determined using the brightest source(s) in the experiment. Look for small dispersion in the phase data, this indicates a high signal to noise ratio - and thus a good bandpass characterisation.
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VPLOT_CAL
Plot of visibilities vs time for all baselines to the reference antenna, after applying CL3. This is a good place to check the success of the amplitude calibration (CL2) and FRING (CL3) stages of the pipeline.
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POSSM_CAL
Amplitude and phase vs frequency plots for all baselines to the reference antenna, after applying CL3 and BP1. If the corrections of CL2, CL3 and BP1 are good enough, you will get flat phase and amplitude profiles, therefore this is a good place to check the success of CL2, CL3 and particularly BP1 for each scan/baseline/IF/Pol.
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IMAPN
Only phase-referenced targets are shown.
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IMAPU
Only phase-referenced targets are shown.
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CALIB_PHAS1
Individual plots for each source that was used in FRING. Shows phase selfcal solutions (SN1 after SPLIT). This is particularly useful to check if the reference source could be self-calibrated, and to look for missing scans/antennas. This is the spectral line pass data. Better solutions are expected in the continuum data.
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CALIB_AMP2
Individual plots for each source that was used in FRING. Shows amplitude selfcal solutions (SN2). This table is important to properly calibrate amplitudes from stations that had to use generic Tsys tables (see TSYS, above). In the statistical summary, values close to one mean a good a-priori calibration.
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SENS
Plot of CL4 which shows amplitude calibrations determined from CL3 and the amplitude selfcal solutions from SN2 (from CALIB_AMP2, above). Comparison with GAIN plot (above) reveals the accuracy of the apriori amplitude calibration derived from the TSYS tables - this is particularly important for stations that have generic generated TSYS tables; Tsys may benefit from additional scaling if there is a large difference in SENS and GAIN plots.
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CLPHS
Closure phases for all triangles of antennas in the array. Individual plots for each source that was used in FRING.
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VPLOT_MODEL
Similar to VPLOT_CAL for sources used in FRING, however, each source has been individually SPLITed and modelled.
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UVCOV
Plot of the UV coverage for each source during the experiment.
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UVPLT
Plot of amplitude vs baseline length for each source. This can be useful to look for indications of structure at different angular scales.
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ICLN
CLEANed image of each source (FRINGed or phase-referenced) after applying all relevant calibrations up to CL4 by the pipeline; including amplitude and phase self calibrations.
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