EVN User Experiment Pipeline Feedback


Pipeline feedback for experiment ER025B. 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 Jan 13 19:44:39 CET 2011 muehle@jive.nl

General Comments. ( Brief data summary and scan listing )
K band (22 GHz) spectral line EVN experiment, observed on 30/31 October 2010. The data rate was 512 Mbps (4 x 16 MHz subbands, dual polarization, two-bit sampling). The target source 'ARP299B1' was calibrated using the phase-reference sources 'J1128+5925'. The calibrator source '4C39.25' was used as fringe finder. In this pipeline reduction, Ef, Mc and On served as reference antennas and On as plot reference, i.e. the plots show baselines to On. The pipeline used AIPS version 31DEC09 and a solution interval of 0.5 min.
7 stations participated in the experiment: Ef, Jb, On, Mc, Mh, Ro and Ys. When the source elevation at Ef was 80 degrees or more (07:36 UT - 09:10 UT), the telescope monitoring log indicates that the antenna was not on source. Therefore this time range has been flagged in the Ef data. At Mh, BBC01 (= IF1/R) is suspected to be broken and BBC02 (= IF1/L) did not lock to the requested low frequency. As a consequence, IF1 of Mh has been flagged for the entire experiment before the pipeline was run. The RCP channels of Jb have very low amplitudes and bad phases, so that they were flagged for the entire experiment as well. The noise diode at Ro did not work properly. Instead, the zenith calibration and an ambient load were used for the calibration. At Ys, the recorder had a sync problem for about 1 minute at 05:43:50 UT (scans #305 and #306). More details about the observations can be found in the letter to the P.I. which is also available from the archive (section "Standard plots").

The EVN reliability indicator (ERI) for this experiment was ERI = 0.78 . ERI* = 0.78 . (EF=1, JB=0.5, ON=1, MC=1, MH=0.75, RO=1, YS=1)

Plots of the autocorrelations
Comments.
in general, bandpasses seem to be stable; Jb: a few strong RFI spikes in IF2/L, IF3/L and IF4/L; low-level RFI spikes at other stations as well; Ro: wiggely bandpasses in LCP, but stable; Ef: data flagged between 07:36 UT and 09:10 UT (high source elevation); Mh: IF1/L+R flagged (see above); Jb: RCP channels flagged (see above); 930 pages

plots of the uncalibrated amplitude and phase against time
Comments.
not unexpectedly, fast phase rotation seen on all baselines; in general, phases of the fringe finder can be followed easily; Ef: data flagged between 07:36 UT and 09:10 UT (high source elevation); Mh: IF1/L+R flagged (see above); Jb: RCP channels flagged (see above); 15 pages

Plots of the uncalibrated amplitude and phase against frequency channel
Comments.
except for the glitches already mentioned, bandpasses seem to be stable; Jb: RFI spikes mentioned above show up in baselines; even uncalibrated, phases of the fringe finder can easily be followed on all baselines; 780 pages

The uncalibrated amplitude and phase of the crosshand correlations against frequency channel (not available)
Comments.

TSYS against time
Comments.
Jb: no Tcal information available; rest of T_sys looks reasonable; Mh: IF1/L+R flagged (see above); On: note that Tsys includes the atmosphere (chopper-wheel calibration), high values of T_sys around 00 UT, likely due to high opacity of the atmosphere (log mentions high humidity); 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; few solutions outside of fringe finder scans for Mh; 5 pages

Fringe-fit delay solutions
Comments.
refant = Ef; delays of the order of (a few tens of) nanoseconds; a few huge outliers; 5 pages

Fringe-fit rate solutions
Comments.
refant = Ef; rates of the order of (a few tens of) mHz; a few huge outliers; 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; Ro: wiggely bandpasses and phases in LCP channels; 2 pages

Calibrated amplitude and phase against time (a priori amplitude calibration and fringe-fit solutions applied).
Comments.
for the fringe finder, phases aligned close to zero, although rather noisy, and amplitudes seem to be stable; 15 pages

Calibrated amplitude and phase against frequency channel
Comments.
amplitudes and phases of the fringe finder look ok; 224 pages

Naturally weighted dirty map (not useful for bright sources) produced before self-cal of:
4C39.25: pdf (not available) , or FITS (not available) .
J1128+5925: pdf (not available) , or FITS (not available) .
ARP299B1: pdf , or FITS .
Comments.

Uniformly weighted dirty map (not useful for bright sources) produced before self-cal of:
4C39.25: pdf (not available) , or FITS (not available) .
J1128+5925: pdf (not available) , or FITS (not available) .
ARP299B1: pdf , or FITS .
Comments.

Phase corrections applied to a priori calibrated and fringe-fitted data by self-calibration.
4C39.25 .
J1128+5925 .
ARP299B1 (not available) .
Comments.
refant = Ef; small phase corrections with only a few hugh outliers for the fringe finder (< 20 deg); significantly larger corrections for the phase-reference source; 5 pages per source

Amplitude corrections applied to a priori calibrated and fringe-fitted data by self-calibration.
4C39.25: pdf , or text file , or statistical summary .
J1128+5925: pdf , or text file , or statistical summary .
ARP299B1: pdf (not available) , or text file (not available) , or statistical summary (not available) .
Comments.
corrections look generally reasonable; Jb, Mh: few solutions found for the phase-reference source; 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.
sensitivities look generally reasonable; Jb, Mh: few solutions, large scatter; 5 pages

Residual closure phase (visibility closure phase with model closure phase subtracted) for:
4C39.25 .
J1128+5925 .
ARP299B1 (not available) .
Comments.
residual closure phases generally clustered around a small value for the fringe finder; very few solutions for the phase-reference source; 7 pages for the fringe finder, 3 pages for the phase-reference source

Calibrated visibilities and the source model of:
4C39.25 .
J1128+5925 .
ARP299B1 (not available) .
Comments.
in general, very good agreement between models and data; 15 pages for the fringe finder, 10 pages for the phase-reference source

Calibrated visibilities against u,v distance for:
4C39.25: pdf , or png .
J1128+5925: pdf , or png .
ARP299B1: pdf , or png .
Comments.

u,v coverage for:
4C39.25: pdf , or png .
J1128+5925: pdf , or png .
ARP299B1: pdf , or png .
Comments.

Crude maps of sources:
4C39.25: pdf , or FITS .
J1128+5925: pdf , or FITS .
ARP299B1: pdf , or FITS .
Comments.