VS06m Results
Submitted checklist.txt and checklist.tex is also available		   [Summary | AIPS | Difmap ]
Analyst: William Scott
Date Prepared: 26-09-2000
 

Summary
 
Observation code : VS06m    AIPS Version : 15Apr99   
Date of Observation : 1998/203    Difmap Version : 2.3c 
Source Name : J1939-15    vsop_difmap used : Yes 
Calibration Source(s) : 1958-179         
Ground telescopes : Hh, Ho, Se  Model Fitted to data : Yes 
Tracking Station(s) : GZ, TZ    Image made : Yes 
Correlator : Penticton         

 
Abstract
Note: This experiment was originally analyzed March 08/1999!

Overall amplitudes seemed lowish (0.5 to 0.8 Jy). Most other observations (PLS etc) pegged the zerospacing flux at about 1.5 Jy. However, PMN gives a flux of 0.8 in 1994, so source could just be variable. There was no AT light curve info. Calibrator does not help, since from AT light curves it appeared to be highly variable.
Model
Flux (Jy)
Radius (mas)
Theta (deg)
Major (mas)
Axial ratio
Phi (deg)
TB (10^12 K)
0.430064 0.0165469 -50.9362 0.256941 0.242836 -41.6827 1.3091
(*) 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 = VS06M.FITLD 
MSORT
 
 
 
 
 Input file name = VS06M.FITLD, Output file name = VS06M.UVSRT 
FIXWT IF=1
CHAN=100
XINC=10
 
 
 
 
  
INDXR CPARM(1)=3
CPARM(3)=0.25
 
 
 
 
 Created NX(1) 
TBOUT INEXT = 'AN'
 
 
 
 
  
TBIN
 
 
 
 
 Changed MNTSTA entries in the AN table. Changed Halca from 3 to 2, and changed all other antennas to 0. 
IBLED
 
 
 
 
 created FG(1) 
ANTAB
 
 
 
 
 Nominal values were used for the DPFU of Ho (0.4). For Ho, the Tsys values seemed corrupted, so a nominal value of 155K was used. For Halca, a nominal Tsys value of 95K was used. Output sent to TY(1) and GC(1). 
APCAL
 
1 
 
 
 Input: Ty(1) + GC(1) 
CLCAL OPCODE = CALP
INTERPOL = 'AMBG'
1 
1 
2 
 
  
FRING DOCALIB 1
GAINUSE 1
REFANT 3 (Ho)
SEARCH 2,4
SOLINT 2
TIMER 0 19 0 0 0 19 30 0
APARM(1)=2
APARM(7)=4 (SNR=4)
APARM(9)=1
DPARM(1)=1 (no baseline
   stacking)
DPARM(2)=1000 (1000ns delay
   window!)
DPARM(3)=100 (100mHz rate
   window)
DPARM(4)=0.5 (0.5 sec integration
   time)
DPARM(6)=1 (don't average
   in frequency)
BCHAN 30, ECHAN 220
CALSOUR='1958-179'
2 
 
 
2 
 Got good solutions for all GRTs..Hh and Se. 
TBOUT INEXT = 'SN'
INVER=2
 
2 
 
 
  
TBIN
 
2 
 
 
 Removed the rate solutions and made sure there was only one solution for the relevant antennas (Ho, Se, Hh). 
CLCAL OPCODE = CALP
INTERPOL = '2PT'
Smotype = VLBI
2 
2 
3 
 
 SN(2) was accidentally deleted after being applied to CL(3) and not regenerated. 
FRING As per previous FRING,
   except:
SOLINT 4
DOCALIB 1
GAINUSE 3
DPARM(7) 3
CALSOUR=''
3 
 
 
3 
 Got good solutions. 
SNEDT
 
3 
 
4 
 Editted inconsistent delays. Rates were not editted, since it was unclear what rates were good/bad solutions. 
CLCAL OPCODE='CALI'
INTERPOL = '2PT'
SMOTYPE = ''
REFANT 3
3 
4 
4 
 
  
TACOP
4 
 
5 
 
  
CLCOR OPCODE 'GAIN'
CLCORPRM 0.9055
5 
 
5 
 
 Correction for Van-Vleck Renormalization 
CLCOR OPCODE 'GAIN'
ANTENNA=1, CLCORPRM=1.07,
   then
ANTENNA=2, CLCORPRM=0.88,
   then
ANTENNA=3, CLCORPRM=1.21,
   then
ANTENNA=4, CLCORPRM=0.82
5 
 
5 
 
 Since I had to go back into AIPS to apply the Van-Vleck correction anyways, I also applied the GSCALE corrections that Difmap generated from the earlier analysis. 
SPLIT SOURCES 'J1939-15'
BCHAN 0, ECHAN 0
DOCALIB 1, GAINUSE 5
APARM(1)=2 (average each
   IF separately)
APARM(2)=0.5
APARM(4)=1
5 
 
 
 
 Input file: VS06M.UVSRT, Output file: J1939-15.FITS 
FITTP
 
 
 
 
 Input file: J1939-15.FITS, Output file: J1939-15.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
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
UVPLT_UV.PS
SN_CALIB_SNR_1.PS		 SN_CALIB_SNR_2.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
No problems cleaning out central component, but not much after that. Tried gscale, but all the corrections were less than 5 percent except for Se, IF2 (was 10 percent). Gscale also flagged out about half the data, so I decided it was not worth it, and didn't use the gscale corrections. Final image was basically unresolved, with a 0.416 Jy/beam core.

Image
Ampl, Phase vs (u,v) Distance
PS (63 kb)
JPEG (47 kb)
 Ampl, Phase vs Time
PS (167 kb)
JPEG 1, 2		 (u,v) Coverage
PS (34 kb)
JPEG (29 kb)
Closure Phase vs Time
PS (119 kb)
JPEG 1		 Clean Image
PS (45 kb)
JPEG (44 kb)
Modelfit
Ampl, Phase vs (u,v) Distance
PS (63 kb)
JPEG (46 kb)
 Ampl, Phase vs Time
PS (166 kb)
JPEG 1, 2		 (u,v) Coverage
PS (34 kb)
JPEG (29 kb)
Closure Phase vs Time
PS (118 kb)
JPEG 1		 Image with model components
PS (59 kb)
JPEG (46 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)
0.430064 0.0165469 -50.9362 0.256941 0.242836 -41.6827 1.3091
(*) Quoted Brightness temperatures assume Gaussian components and are in the local (z=0) frame.


Last updated on Wed May 23 05:49:44 GMT 2001
by db_results.pl version 0.3.