vs04w Results
Submitted checklist.txt and checklist.tex is also available
  [Summary | AIPS | Difmap ]
Analyst: Laszlo Mosoni
Date Prepared: 06-11-2000
 

Summary
 
Observation code : vs04w    AIPS Version : 15APR99   
Date of Observation : 1998/176    Difmap Version : 2.3c 
Source Name : J2000-1748    vsop_difmap used : No 
Calibration Source(s) :          
Ground telescopes : Hobart, Shanghai  Model Fitted to data : Yes 
Tracking Station(s) : TZ, NZ    Image made : Yes 
Correlator : Penticton         

 
Abstract
Two ground stations, compact core, circular Gaussian model fitted.
Model
Flux (Jy)
Radius (mas)
Theta (deg)
Major (mas)
Axial ratio
Phi (deg)
TB (10^12 K)
1.91944 0.0234853 120.206 0.220079 1.00000 140.194 1.9339
(*) 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
 
 
 
 
 
MSORT
 
 
 
 
uv file received was already sorted in TB order 
FIXWT bif = 1
bchan = 100
xinc = 10
detime = -1
 
 
 
 
 
INDXR cparm = 0, 0, 0.5, 0
 
 
 
Input scan break taken from PI letter 
TABED inext = 'an'
inver = 1
outver = 1
optyp = 'repl'
aparm = 5, 0, 0, 6, 0
bcount = 1
ecount = 1
keyvalue = 0
 
 
 
 
fix incorrect antenna type (MNTSTA: altaz ->0) in column 5, row 1 of AN table for HOBART 
TABED same as above, except:
bcount = 2
ecount = 2
keyvalue = 2, 0 (?)
 
 
 
 
fix incorrect antenna type (MNTSTA: orbiter->2) in column 5, row 2 of AN table for VSOP_SC 
ANTAB
 
 
 
 
gain curve informatin from VSOP calibration web page. Nominal Tsys used for Hobart and HALCA. Slight difference between HALCA IF1 and IF2 (96 & 102 K) based on earlier experience. 
APCAL
 
 
 
 
CLCAL opcode = 'cali'
interpol = '2pt'
REFANT = 0
 
Amplitude calibration solutions applied 
TACOP
 
 
 
CLCOR opcode = 'SBDL'
antenn = 1,0
gainver = 3
clcorprm = -2400, -2400
 
 
 
 
Delays from DQA1 plots for Hobart 
FRING docalib = 1
gainuse = 3
flagver = 1
refant = 1
solint = 5
aparm = 2, 0, 0, 0, 2, 1,
   3, 0, 1, 0
dparm = 3, 400, 100, 0
 
 
Delay and rate search windows 400 ns and 100 mHz, SNR treshhold 3. 556 good solutions. 
TACOP
 
 
For clipping in SNSMO 
SNSMO timer = 0 13 0 0 0 16 0 0
interpol = 'MWF'
doblank = 1
smotype = 'DELA'
cparm(5) = 30
cparm(10) = 35
 
 
Data editing for HALCA 
SNSMO same as above, except:
bparm(5) = 0.2
 
 
Interpolation 
CLCAL opcode = 'cali'
interpol = 'ambg'
 
Fringe-fit solution applied. 
TACOP
 
 
 
TACOP
 
 
(mistake) 
CLCOR opcode = 'gain'
antenna = 0
clcorprm = 0.906, 0
 
 
Gain correction for Penticton data correlated before 14 Feb 1999, (14 Aug 1998). 
TACOP
 
 
Prepare a copy before amplitude scaling. 
CLCOR opcode = 'gain'
antenna = 1, 0
clcorprm = 0.625, 0
 
 
Hobart gain correction after investigating data in Difmap. 
CLCOR opcode = 'gain'
antenna = 3, 0
clcorprm = 1.6, 0
 
 
Seshan gain correction after investigating data in Difmap. 
SPLIT aparm = 2, 0.7246, 0, 1, 0
bchan = 20
 
 
 
Create single-source file, IFs not averaged, aparm(2) from DTSUM 
FITTP
 
 
 
 
Data written out for analysis in Difmap. 

AIPS Input Files
ANTAB.TXT Comments
Measured Tsys for Seshan, nominal values for HALCA and Hobart.

AIPS Output Files
DTSUM_0.LIS
DTSUM_1.LIS
LISTR.LIS
PRTAN.LIS
POSSM01_AP_1.PS
POSSM01_AP_2.PS
POSSM02_AP_1.PS
POSSM02_AP_2.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



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
Amplitude scaling was based on pre-launch survey and uv-crossing points. Clean component model was obtained after a few iterations of clean/phase-only selfcal. Single circular Gaussian component fits the uv data perfectly.

Image
Ampl, Phase vs (u,v) Distance
PS (51 kb)
JPEG (43 kb)
Ampl, Phase vs Time
PS (123 kb)
JPEG 1, 2
(u,v) Coverage
PS (26 kb)
JPEG (28 kb)
Closure Phase vs Time
PS (52 kb)
JPEG 1
Clean Image
PS (34 kb)
JPEG (43 kb)
Modelfit
Ampl, Phase vs (u,v) Distance
PS (51 kb)
JPEG (43 kb)
Ampl, Phase vs Time
PS (123 kb)
JPEG 1, 2
(u,v) Coverage
PS (26 kb)
JPEG (28 kb)
Closure Phase vs Time
PS (51 kb)
JPEG 1
Image with model components
PS (37 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)
1.91944 0.0234853 120.206 0.220079 1.00000 140.194 1.9339
(*) Quoted Brightness temperatures assume Gaussian components and are in the local (z=0) frame.



Last updated on Tue Dec 19 03:01:33 GMT 2000
by db_results.pl version 0.3.