VS02f Results
Submitted checklist.txt and checklist.tex is also available		   [Summary | AIPS | Difmap ]
Analyst: William Scott
Date Prepared: 25-11-1999
 

Summary
 
Observation code : VS02f    AIPS Version : 15Apr99   
Date of Observation : 1999/84    Difmap Version : 2.3c 
Source Name : J1723-65    vsop_difmap used : Yes 
Calibration Source(s) : 1954-388         
Ground telescopes : AT, Ho, Hh  Model Fitted to data : Yes 
Tracking Station(s) : NZ, TZ    Image made : Yes 
Correlator : Penticton         

 
Abstract
Checklist changed. Incorrect day number given. JEJL 27-Nov-2000
Model
Flux (Jy)
Radius (mas)
Theta (deg)
Major (mas)
Axial ratio
Phi (deg)
TB (10^12 K)
4.86177 0.0488873 -160.826 0.947506 1.00000 40.2887 0.2643
(*) 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 = VS02f.FITLD 
MSORT
 
 
 
 
 Input file name = VS02f.FITLD, Output file name = VS02f.UVSRT 
INDXR
 
 
 
 
 Created NX(1) 
ANTAB
 
 
 
 
 Used Tsys values of 89,93K for Halca. For the AT, used nominal values. For the AT, CA01 died from 01:29 - 01:39, so the Tsys values were adjusted to reflect this. Output sent to TY(1) and GC(1). 
APCAL
 
1 
 
 
 Input: Ty(1) + GC(1) 
CLCAL OPCODE = CALP
INTERPOL = 'AMBG'
REFANT 1 (AT)
1 
1 
2 
 
  
TBOUT INEXT = 'AN'
 
 
 
 
  
TBIN
 
 
 
 
 Changed MNTSTA entries in the AN table. Changed Halca from 3 to 2, changed Hobart from 2 to 0, and change Hart from 1 to 0. 
TBIN
 
 
 
2 
 Read in DQA1 delay and rate solutions, although I editted out one low SNR solution for Halca beforehand, since I was not sure it was legitimate. 
CLCAL OPCODE = CALP
INTERPOL = 'AMBG'
REFANT 1 (AT)
2 
2 
3 
 
  
FRING DOCALIB 1
GAINUSE 3
REFANT 1 (AT)
SEARCH 2,3
SOLINT 1
APARM(1)=2
APARM(7)=3 (SNR=3)
APARM(9)=1
DPARM(1)=3 (include baseline
   stacking)
DPARM(2)=100 (100ns delay
   window!)
DPARM(3)=50 (50mHz rate
   window)
DPARM(4)=0.5 (0.5 sec integration
   time)
DPARM(6)=1 (don't average
   in frequency)
BCHAN 0, ECHAN 0
DOFIT 1,2,3
3 
 
 
3 
 Got good solutions for all GRTs. 
SNEDT
 
3 
 
4 
  
CLCAL OPCODE='CALP'
INTERPOL = 'AMBG'
SMOTYPE = ''
REFANT 1
3 
4 
4 
 
  
FRING DOCALIB 1
GAINUSE 4
FLAGVER -1
REFANT 1 (AT)
SOLINT 5
APARM(1)=2
APARM(7)=2 (SNR=2)
APARM(9)=1
DPARM(1)=3 (include baseline
   stacking)
DPARM(2)=100 (100ns delay
   window!)
DPARM(3)=50 (50mHz rate
   window)
DPARM(4)=0.5 (0.5 sec integration
   time)
DPARM(6)=1 (don't average
   in frequency)
BCHAN 0, ECHAN 0
DOFIT 1,4
4 
 
 
5 
 Needed FLAGVER=-1, since most of the AT-Ha baseline was flagged out due to NO PRC/ LOW DVAL. After many attempts, only got a very small range of good solutions for Halca. In retrospect, this probably makes sense, since it looked like the source was resolved out on UV distances greater than 150 Mlambdas. The solutions obtained for Halca corresponded to some of the shortest SVLBI baselines. 
CLCAL OPCODE='CALP'
INTERPOL = 'AMBG'
SMOTYPE = ''
REFANT 1
4 
5 
5 
 
 Unfortunately, the DOFIT in the last FRING does not seem to want to work. CL(5) only contains solutions where Halca was on line. Since there does not seem to be much improvement in solutions from CL(5) to CL(4), (checked by using POSSM), will use CL(4) instead of CL(5). 
TACOP
4 
 
6 
 
  
CLCOR ANTENNAS=0
OPCODE=GAIN
CLCORPRM=2
GAINVER=6
6 
 
6 
 
 Global correction to pull short-spacings in line with AT light curve values for both J1723-65 and 1954-388. Even though the last recorded AT value for J1723-65 was made on Feb. 98, the source was reasonably constant over 1 year time spans. 
SPLIT SOURCES 'J0115-01'
BCHAN 0, ECHAN 0
DOCALIB 1, GAINUSE 6
APARM(1)=2 (average each
   IF separately)
APARM(2)=0.5
APARM(4)=1
4 
 
 
 
 Input file: VS02f.UVSRT, Output file: J1723-65.FITS 
FITTP
 
 
 
 
 Input file: J1723-65.FITS, Output file: J1723-65.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
SN_CALIB_SNR_1.PS
SN_CALIB_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
As a starting model used a circular Gaussian instead of clean components. Gscale flagged most of the data (most of the time there was not four co-observing antennas whose visibilities were not previously flagged), and the corrections it gave were extremely large, so did not end up using it. For phase self-cal, the smallest solint I used was 5 minutes. Final image: Had a 1.72Jy/beam core, and was resolved out on UV distances greater than 150 Mlambdas.

Image
Ampl, Phase vs (u,v) Distance
PS (25 kb)
JPEG (34 kb)
 Ampl, Phase vs Time
PS (117 kb)
JPEG 1, 2		 (u,v) Coverage
PS (16 kb)
JPEG (27 kb)
Closure Phase vs Time
PS (98 kb)
JPEG 1		 Clean Image
PS (54 kb)
JPEG (49 kb)
Modelfit
Ampl, Phase vs (u,v) Distance
PS (25 kb)
JPEG (35 kb)
 Ampl, Phase vs Time
PS (113 kb)
JPEG 1, 2		 (u,v) Coverage
PS (16 kb)
JPEG (27 kb)
Closure Phase vs Time
PS (96 kb)
JPEG 1		 Image with model components
PS (38 kb)
JPEG (40 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)
4.86177 0.0488873 -160.826 0.947506 1.00000 40.2887 0.2643
(*) Quoted Brightness temperatures assume Gaussian components and are in the local (z=0) frame.


Last updated on Wed Aug 25 07:20:37 GMT 2004
by db_results.pl version 0.3.