VS08y Results
Submitted checklist.txt and checklist.tex is also available		   [Summary | AIPS | Difmap ]
Analyst: William Scott
Date Prepared: 23-08-2000
 

Summary
 
Observation code : VS08y    AIPS Version : 15Apr99   
Date of Observation : 1999/246    Difmap Version : 2.3c 
Source Name : J1640+39    vsop_difmap used : Yes 
Calibration Source(s) : 1611+343         
Ground telescopes : Nt, Ka  Model Fitted to data : Yes 
Tracking Station(s) : RZ    Image made : Yes 
Correlator : Penticton         

 
Abstract
Data extraction experiment from GOT experiment W055h.
Model
Flux (Jy)
Radius (mas)
Theta (deg)
Major (mas)
Axial ratio
Phi (deg)
TB (10^12 K)
0.601397 0.0272605 165.996 0.361292 0.817336 -53.8420 0.2751
(*) 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 DIGICOR=DELCOR=-1
 
 
 
 
 Output file name = VS08y.FITLD 
MSORT
 
 
 
 
 Input file name = VS08y.FITLD, Output file name = VS08y.UVSRT 
INDXR
 
 
 
 
 Created NX(1) 
ANTAB
 
 
 
 
 Used Tsys values of 88,92K for Halca. Used Nominal gain curves for Ka, Nt. For Ka, used a nominal Tsys of 171K. Output sent to TY(1) and GC(1). 
APCAL
 
1 
 
 
 Input: Ty(1) + GC(1) 
CLCAL OPCODE = CALP
INTERPOL = 'AMBG'
REFANT 2 (Nt)
1 
1 
2 
 
  
TBOUT INEXT = 'AN'
 
 
 
 
  
TBIN
 
 
 
 
 Changed MNTSTA entries in the AN table. Changed Halca from 3 to 2, and changed all other antennas to 0. 
TBIN
 
 
 
2 
 Read in DQA1 delay and rate solutions. 
SNEDT
 
2 
 
3 
 Extremely minor editting. 
CLCAL OPCODE = CALP
INTERPOL = 'AMBG'
REFANT 2 (Nt)
2 
3 
3 
 
  
FRING DOCALIB 1
GAINUSE 3
REFANT 2 (Nt)
SEARCH 1
SOLINT 3
TIMER 0 10 45 0 0 11 0 0
APARM(1)=2
APARM(7)=2 (SNR=2)
APARM(9)=1
DPARM(1)=3 (include baseline
   stacking)
DPARM(2)=50 (50ns delay
   window!)
DPARM(3)=20 (20mHz rate
   window)
DPARM(4)=0.5 (0.5 sec integration
   time)
DPARM(6)=1 (don't average
   in frequency)
BCHAN 0, ECHAN 0
3 
 
 
4 
 Except for the initial solution near the timerange boundary got good solutions. Try the entire time range with a larger SNR cutoff. 
FRING As above but with:
TIMER 0
APARM(7) 5
3 
 
 
5 
 Got great solutions. I think I can reduce my windows still further. 
FRING As above but with:
DPARM(2)=20 (20ns delay
   window!)
DPARM(3)=10 (10mHz rate
   window)
3 
 
 
6 
 Solutions looked good...go with these. 
SNEDT
 
6 
 
7 
 Minor editting. 
CLCAL OPCODE='CALP'
INTERPOL = 'AMBG'
SMOTYPE = ''
REFANT 1
3 
7 
4 
 
  
CLCOR
 
 
 
 
 Did not use. Baselines at 150Mlambdas were slightly lower (0.5Jy) than the PLS (0.7), but for all I know this could be due to source variability. Relative amplitudes seem ok, since the radplot looks reasonalbly continuous. There were no crossing points to check. 
SPLIT SOURCES 'J1640+39'
BCHAN 0, ECHAN 0
DOCALIB 1, GAINUSE 4
APARM(1)=2 (average each
   IF separately)
APARM(2)=0.5
APARM(4)=1
4 
 
 
 
 Input file: VS08y.UVSRT, Output file: J1640+39.FITS No FRING solutions were found for the calibrator (had only one baseline anyhow), so did not bother SPLITing it. 
FITTP
 
 
 
 
 Input file: J1640+39.FITS, Output file: J1640+39.FITS amplitude 

AIPS Input Files
ANTAB.TXT
INDXR.TXT		 Comments
- None -

AIPS Output Files
DTSUM_0.LIS
DTSUM_1.LIS
LISTR.LIS
PRTAN.LIS
POSSM01_AP_1.PS
POSSM02_AP_1.PS
POSSM03_AP_1.PS
SN_APCAL_AMP_1.PS
SN_APCAL_AMP_2.PS
SN_CALIB_DEL_1.PS		 SN_CALIB_DEL_2.PS
SN_CALIB_PHA_1.PS
SN_CALIB_PHA_2.PS
SN_CALIB_RAT_1.PS
SN_CALIB_RAT_2.PS
SN_CALIB_SNR_1.PS
SN_CALIB_SNR_2.PS
SN_FRING01_DEL_1.PS
SN_FRING01_DEL_2.PS
SN_FRING01_RAT_1.PS		 SN_FRING01_RAT_2.PS
SN_FRING01_SNR_1.PS
SN_FRING01_SNR_2.PS
UVPLT_UV.PS
UVPLT_UVD.PS
UVPLT_UVPA.PS
VPLOT_AP_1.PS
VPLOT_AP_2.PS
WEIGHTS.PS


Difmap Data Reduction Notes
Phase selfcal applied? Yes
Global amplitude selfcal (gscal) applied? No
Amplitude selfcal on non-global timescales used? No
Modelfit made and saved? Yes
Image Made and saved? Yes
Comments on Difmap processing
Used the default 1 Jy source as a starting model. Needed to use uvtaper 0.5,150 to pick up the shorter spacing flux on later clean/phase-self-cal iterations. For the final round of clean/phase self-cal, there looked to be a possible residual to the SW. However, this also corresponded approximately to the position of a beam sidelobe, so no clean components were added for this residual. Final image: Had a 0.363 Jy/beam core. At the longest spacings the source was mostly resolved out.

Image
Ampl, Phase vs (u,v) Distance
PS (21 kb)
GIF (6 kb)
 Ampl, Phase vs Time
PS (64 kb)
GIF 1, 2		 (u,v) Coverage
PS (12 kb)
GIF (4 kb)
Closure Phase vs Time
PS (44 kb)
GIF 1		 Clean Image
PS (36 kb)
GIF (74 kb)
Modelfit
Ampl, Phase vs (u,v) Distance
PS (21 kb)
GIF (6 kb)
 Ampl, Phase vs Time
PS (64 kb)
GIF 1, 2		 (u,v) Coverage
PS (12 kb)
GIF (4 kb)
Closure Phase vs Time
PS (43 kb)
GIF 1		 Image with model components
PS (38 kb)
GIF (7 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)
0.601397 0.0272605 165.996 0.361292 0.817336 -53.8420 0.2751
(*) Quoted Brightness temperatures assume Gaussian components and are in the local (z=0) frame.


Last updated on Wed Aug 30 05:13:56 GMT 2000
by db_results.pl version 0.2.0.