EVN User Experiment Pipeline Feedback
Last updated: Tue Aug 4 18:36:19 CEST 2009
muehle@jive.nl
General Comments.
(
Brief data summary
and
scan listing
)
C band (5 GHz) global VLBI experiment, observed on 27/28 February 2009. The data rate was 512 Mbps (4 x 16 MHz subbands, dual polarization, two-bit sampling). The target source 'Arp220' was calibrated using the phase-reference source 'J1532+2344'. 'J1516+1932', 'J1613+3412' and 'OQ208' were also observed as fringe finder ('OQ208') and calibrators. In this pipeline reduction, Ef served as reference antenna. The plots show baselines to either Ef or Hn.
8 EVN stations (Ef, Jb, On, Mc, Nt, Tr, Wb, Ar) and 9 VLBA stations (Sc, Hn, Nl, Fd, La, Pt, Kp, Ov, Br) were scheduled in this experiment. Ef briefly dropped out of the schedule for pointing checks at 02:37-02:48 UT and 07:38-08:01 UT. At Jb, the MkII telescope was used for this experiment. On was left out of the schedule while Ar participated (08:00-10:45 UT). Tr came in 24 minutes late because their Mk5A hung. Wb observed in phased array mode and only for 12 hours because of its HA restrictions.
The EVN reliability indicator (ERI) for this experiment was
ERI = 0.99 . ERI* = 0.99 .
(Ef=1, Jb=1, On=1, Mc=1, Nt=1, Tr=0.97, Wb=1, Ar=1)
Plots of the autocorrelations
Comments.
stable bandpasses; Jb: low-level RFI in IF1+2/L, at times also in RCP, IF4/R has a wiggely bandpass; Mc: low-level RFI in IF1+2+4/L; at times (traces of) RFI at other stations, too; Wb: wiggely bandpasses; La: IF2/R wiggely bandpass; 1080 pages
plots of the uncalibrated amplitude and phase
against time
Comments.
looking fine; phases can be followed even in the uncalibrated data; 64 pages
Plots of the uncalibrated amplitude and phase
against frequency channel
Comments.
phases can be followed in calibrators; Br: phase wraps in IF4/R; Hn: phase wrap in IF4/R after ~08:00 UT; stable bandpasses; 1526 pages
The uncalibrated amplitude and phase of the crosshand
correlations against frequency channel
Comments.
in general, phases of OQ208 and J1516+19 look good on EVN baselines and on baselines to Nl and Ar, noisier on longer/less sensitive baselines; 825 pages
TSYS against time
Comments.
On: 08:00-10:45 UT On out, while Ar in -> no T_sys measurements; Nt: T_sys in LCP channels slightly higher than in RCP channels; Tr: increased T_sys at ~02:00-02:30 UT; Fd: increased T_sys at ~05:10 UT; La: jump in T_sys at ~05:10 UT; Pt: narrow spike in T_sys at ~05:10 UT; Kp: increased T_Sys at ~05:45-06:00 UT; Ov: high T_sys until ~06:50 UT; Br: spike in T_sys at ~05:30 UT; 14 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.
curves match closely those of T_sys vs. time; 14 pages
Fringe-fit phase solutions
(including Parallactic
Angle correction).
Comments.
reference antenna: Ef, drift in phases reflects the parallactic angle correction; fast phase rotation when elevation of the source is low at the station; 14 pages
Fringe-fit delay solutions
Comments.
reference antenna: Ef; delays of the order of (a few tens of) nanoseconds, a few outliers; 14 pages
Fringe-fit rate solutions
Comments.
reference antenna: Ef; except for some outliers, rates of the order of mHz; 14 pages
Telescope bandpasses
Comments.
reference antenna: Ef; bandpasses look good, phases generally close to zero; 4 pages
Calibrated amplitude and phase against time
(a
priori amplitude calibration and fringe-fit solutions applied).
Comments.
looking good; 64 pages
Calibrated amplitude and phase against frequency
channel
Comments.
nothing unexpected detected; just a few instances of bad data, e.g. Fd/IF3R at 06:14 UT and Tr/IF3R,4R+L at 09:26 UT; 1502 pages
Naturally weighted dirty map (not useful for bright sources)
produced before self-cal of:
OQ208: pdf (not available)
, or
FITS (not available)
.
J1516+1932: pdf (not available)
, or
FITS (not available)
.
ARP220:
pdf
, or
FITS
.
J1613+3412: pdf (not available)
, or
FITS (not available)
.
J1532+2344: pdf (not available)
, or
FITS (not available)
.
Comments.
According to the cover letter of the schedule, the cores of Arp220 are located 400 milliarcsec from the pointing center.
Uniformly weighted dirty map (not useful for bright sources)
produced before self-cal of:
OQ208: pdf (not available)
, or
FITS (not available)
.
J1516+1932: pdf (not available)
, or
FITS (not available)
.
ARP220:
pdf
, or
FITS
.
J1613+3412: pdf (not available)
, or
FITS (not available)
.
J1532+2344: pdf (not available)
, or
FITS (not available)
.
Comments.
According to the cover letter of the schedule, the cores of Arp220 are located 400 milliarcsec from the pointing center.
Phase corrections applied to a priori calibrated and
fringe-fitted data by self-calibration.
OQ208
.
J1516+1932
.
ARP220 (not available)
.
J1613+3412
.
J1532+2344
.
Comments.
refant: Ef; except for some outliers, all the phase corrections are within a couple of degrees for the calibrators, a bit larger for the phase-reference source; 14 pages per source
Amplitude corrections applied to a priori calibrated and
fringe-fitted data by self-calibration.
OQ208:
pdf
, or
text file
, or
statistical summary
.
J1516+1932:
pdf
, or
text file
, or
statistical summary
.
ARP220: pdf (not available)
, or
text file (not available)
, or
statistical summary (not available)
.
J1613+3412:
pdf
, or
text file
, or
statistical summary
.
J1532+2344:
pdf
, or
text file
, or
statistical summary
.
Comments.
looks ok; corrections a bit larger than usual in a few channels (Jb/2L, Nt/1-4R, La/2R); 14 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.
a few narrow spikes in the data, rest looks ok; 14 pages
Residual closure phase (visibility closure phase with model closure phase subtracted) for:
OQ208
.
J1516+1932
.
ARP220 (not available)
.
J1613+3412
.
J1532+2344
.
Comments.
nothing unexpected detected; a couple of outliers; 77 pages per source
Calibrated visibilities and the source model of:
OQ208
.
J1516+1932
.
ARP220 (not available)
.
J1613+3412
.
J1532+2344
.
Comments.
generally very good agreement between data and models; a few outliers; 64 pages per source
Calibrated visibilities against u,v distance for:
OQ208:
pdf
, or
png
.
J1516+1932:
pdf
, or
png
.
ARP220:
pdf
, or
png
.
J1613+3412:
pdf
, or
png
.
J1532+2344:
pdf
, or
png
.
Comments.
u,v coverage for:
OQ208:
pdf
, or
png
.
J1516+1932:
pdf
, or
png
.
ARP220:
pdf
, or
png
.
J1613+3412:
pdf
, or
png
.
J1532+2344:
pdf
, or
png
.
Comments.
Crude maps of sources:
OQ208:
pdf
, or
FITS
.
J1516+1932:
pdf
, or
FITS
.
ARP220:
pdf
, or
FITS
.
J1613+3412:
pdf
, or
FITS
.
J1532+2344:
pdf
, or
FITS
.
Comments.
According to the cover letter of the schedule, the cores of Arp220 are located 400 milliarcsec from the pointing center.