VS07I Results
Submitted checklist.txt and checklist.tex is also available		   [Summary | AIPS | Difmap ]
Analyst: Richard Dodson
Date Prepared: 18-05-2005
 

Summary
 
Observation code : VS07I    AIPS Version : 31DEC03   
Date of Observation : 2001/354    Difmap Version : 2.3c 
Source Name : J1127-18    vsop_difmap used : Yes 
Calibration Source(s) : J1215-17,J1337-12         
Ground telescopes : Cd Ho Mo Sh  Model Fitted to data : Yes 
Tracking Station(s) : Tz Rz    Image made : Yes 
Correlator : Penticton         

 
Abstract
Nice model/image -- but some trouble with the amplitudes.

On J1337-12 I can see Hobart down by 10 and Ceduna by 2. On the target (J1127-18) a single value was not sufficient and a Ceduna only amplitude selfcal was done on 10 min time scale
Model
Flux (Jy)
Radius (mas)
Theta (deg)
Major (mas)
Axial ratio
Phi (deg)
TB (10^12 K)
0.587193 0.0649399 148.153 0.324123 0.515426 -41.0585 0.5292
0.135468 1.51877 147.584 0 0 0 0.0000
(*) Quoted Brightness temperatures assume Gaussian components and are in the local (z=0) frame.


AIPS Data Reduction Notes
 
Task
Adverbs
CL
in
SN
in
CL
out
SN
out
Comments
FITLD clint = 0.25
digicor = -1
delcorr = -1
 
 
 
 
  
INDXR cparm = 0, 0, 0.25;
 
 
1 
 
  
ANTAB infile='antab.txt'
 
 
 
 
 Ceduna is unscaled 
APCAL
 
 
 
1 
  
CLCAL refant=1;
1 
1 
2 
 
 Amplitude calibration solutions applied. 
FRING docal -1; dparm 2,400,400,0.5,0;aparm(7)=0.1;solint
   5,10,15
 
 
 
3,4,5 
 Full range searched 
FRING dparm
   2,0,0,0.5,0;aparm(7)=0.1;solint
4 
 
 
6 
  
CLCAL interp 'ambg'/''cube'/'self'
2 
 
3,4,5 
 
 Cubic is best 
SPLIT aparm(1)=2 0;
4 
 
 
 
 Av within IF 
FITTP
 
 
 
 
 Data written out for analysis in Difmap amplitude 

AIPS Input Files
ANTAB.TXT Comments
used nominal_tsys.pl

AIPS Output Files
PRTAN.LIS
LISTR.LIS
DTSUM_0.LIS
DTSUM_1.LIS
VPLOT.PS
POSSM.PS
UVPLT_UV.PS		 UVPLT_UVD.PS
UVPLT_UVPA.PS
SN_APCAL_AMP_2.PS
SN_APCAL_AMP_1.PS
SN_CALIB_DEL_1.PS
SN_CALIB_DEL_2.PS
SN_CALIB_RAT_1.PS		 SN_CALIB_RAT_2.PS
SN_CALIB_SNR_1.PS
SN_CALIB_SNR_2.PS
SN_CALIB_PHA_1.PS
SN_CALIB_PHA_2.PS
IMAGE.FITS


Difmap Data Reduction Notes
Phase selfcal applied? Yes
Global amplitude selfcal (gscal) applied? No
Amplitude selfcal on non-global timescales used? Yes
Modelfit made and saved? Yes
Image Made and saved? Yes
Comments on Difmap processing
Amplitude selfcal on Ceduna (only) was performed. Ceduna has jumps in the signal level (that are not related to the ANTAB).

A simple model was fitted to allow for this - cleaning tended to try and reproduce the amplitudes.

Once a good Ceduna amplitude was achieved the image and model looked very similar. Extended source with a second component to the South.

The PLS model was a point source of greater flux.

Noise looks high. Hobart must have observed the wrong polarisation.

Image
Ampl, Phase vs (u,v) Distance
PS (51 kb)
JPEG (39 kb)
 Ampl, Phase vs Time
PS (200 kb)
JPEG 1, 2, 3		 (u,v) Coverage
PS (27 kb)
JPEG (25 kb)
Closure Phase vs Time
PS (228 kb)
JPEG 1, 2		 Clean Image
PS (32 kb)
JPEG (44 kb)
Modelfit
Ampl, Phase vs (u,v) Distance
PS (51 kb)
JPEG (39 kb)
 Ampl, Phase vs Time
PS (201 kb)
JPEG 1, 2, 3		 (u,v) Coverage
PS (27 kb)
JPEG (25 kb)
Closure Phase vs Time
PS (228 kb)
JPEG 1, 2		 Image with model components
PS (32 kb)
JPEG (38 kb)

More details on the Images and Modelfits are found in this page.

Model
Flux (Jy)
Radius (mas)
Theta (deg)
Major (mas)
Axial ratio
Phi (deg)
TB (10^12 K)
0.587193 0.0649399 148.153 0.324123 0.515426 -41.0585 0.5292
0.135468 1.51877 147.584 0 0 0 0.0000
(*) Quoted Brightness temperatures assume Gaussian components and are in the local (z=0) frame.


Last updated on Fri Apr 22 11:35:41 GMT 2005
by db_results.pl version 0.3.