VS03e Results
Submitted checklist.txt and checklist.tex is also available		   [Summary | AIPS | Difmap ]
Analyst: Zhi-Qiang Shen
Date Prepared: 16-11-1999
 

Summary
 
Observation code : VS03e    AIPS Version : 15APR99   
Date of Observation : 1998/231    Difmap Version : 2.3c 
Source Name : J0405-13    vsop_difmap used : Yes 
Calibration Source(s) : 0420-014         
Ground telescopes : Seshan25, Mop  Model Fitted to data : Yes 
Tracking Station(s) : GZ, RZ    Image made : Yes 
Correlator : Penticton         

 
Abstract
This is a 2 GRTs VSOP survey experiment.

Fringes were clearly detected on all three (1 ground-ground and 2 ground-space) baselines.

Since only 3 antennas (including Halca) available, imaging was done without any amplitude self-cal.

Single circular Gaussian component model was fit the calibrated data.

For calibrator 0420-014, fringes were detected on the ground baseline (Seshan25 - Mop) of 6,500km with a correlated flux density of 1.2Jy.
Model
Flux (Jy)
Radius (mas)
Theta (deg)
Major (mas)
Axial ratio
Phi (deg)
TB (10^12 K)
0.420714 0.0815128 46.7528 0.184059 1.00000 0.00000 0.6060
(*) 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 douvcomp=1
dotable=1
 
 
 
 
 load the uv FITS data 
MSORT sort='TB'
 
 
 
 
 sort the data to 'TB' order 
INDXR cparm(3)=0.25
 
 
1 
 
 index uv data with 0.25 min CL entry interval 
TACOP
1 
 
2 
 
 protect CL1 
ANTAB
 
 
 
 
 determine the Tsys and gain curve (Tsys=88K and 92K for IF1 and IF2 of Halca, respectively) 
APCAL opcode=' '
 
 
 
1 
 generate an amplitude calibration solution table 
CLCAL opcode='CALI';smotype='ampl';refant=0
2 
1 
3 
 
 apply amplitude calibration solution 
KRING docalib=1;refant=3;solint=4;flagv=-1
soltype='NOLS';solmode='SBD'
bparm=0;cparm=0,0,1,0
antwt=30,1,1
prtlev=2
3 
 
 
3 
 run FFT (NOLS) KRING with an SNR cutoff=5 to check the fringes ranges 
TACOP
3 
 
4 
 
 protect CL3 from further calibration 
CLCOR opcode='SBDL'
antenna=2,0;clcorprm=105,105,0;timer=0
(antenna=1,0;clcorprm=334,334,0;timer=0,0,0,0,0,17,18,49;
antenna=1,0;clcorprm=410,410,0;timer=0,17,18,49,0,17,29,49;
antenna=1,0;clcorprm=253,253,0;timer=0,18,0,0,0,0,0,0)
4 
 
4 
 
 apply delay offset from KRING solutions to each IF residual delay for antenna 1 (Halca) and 2 (Seshan25). 
FRING docalib=1;flagv=-1;refant=3;solint=4
search=2,1;
aparm=2,0,0,0,0,1,3,0,1,0
dparm=1,200,200,0
antwt=30,1,1
4 
 
 
5 
 fringe fit (FFT+LLS) in narrow searching windows with an SNR cutoff=3 
CLCAL opcode='CALP';smotype='VLBI';interpol='ambg';refant=3
sour=cals='J0405-13'
(sour=cals='0420-014')
4 
5 
5 
 
 apply FRING solutions 
TACOP
5 
 
6 
 
 protect CL5 
CLCOR antenna=0;opcode='GAIN';clcorprm=0.91,0
6 
 
6 
 
 Penticton gain correction 
TASAV
 
 
 
 
 copy all extension tables to a dummy file 
SPLIT docalib=1;douvcomp=1;aparm=2,0;flagv=-1
bchan=25;echan=215
6 
 
 
 
 make calibrated single-source data files: J0405-13.SPLIT and 0420-014.SPLIT (some edge channels have been thrown away) 
FITTP
 
 
 
 
 export each single-source file in FITS format to disk file for further imaging analysis 

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

AIPS Output Files
PRTAN.LIS
LISTR.LIS
DTSUM_0.LIS
DTSUM_1.LIS
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
POSSM01_AP_1.PS
POSSM01_AP_2.PS
VPLOT_AP_2.PS
VPLOT_AP_1.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
average data over 30 sec (uvaver 30,true)

raise the weight of HALCA (selfant VSOP_SC,false,30)

keep non-closing data during phase self-cal (selfflag false,3,4)

clean and phase self-cal with uniform weighting (uvw 2,-1 ... etc)

(*NO* amplitude self-cal with only 3 antennas available)

finish with a uniform weighting clean image: peak=0.395 Jy/beam, RMS=5.1 mJy/beam; beam=0.663 mas x 0.366 mas @ 35.2 deg

A circular Gaussian component (0.42Jy and 0.18mas) was fit the calibrated data.

For calibrator 0420-014, fringes were detected on the ground baseline (Seshan25 - Mop) of 6,500km with a correlated flux density of 1.2Jy.

Image
Ampl, Phase vs (u,v) Distance
PS (34 kb)
JPEG (41 kb)
 Ampl, Phase vs Time
PS (88 kb)
JPEG 1, 2		 (u,v) Coverage
PS (18 kb)
JPEG (27 kb)
Closure Phase vs Time
PS (53 kb)
JPEG 1		 Clean Image
PS (33 kb)
JPEG (43 kb)
Modelfit
Ampl, Phase vs (u,v) Distance
PS (34 kb)
JPEG (41 kb)
 Ampl, Phase vs Time
PS (88 kb)
JPEG 1, 2		 (u,v) Coverage
PS (18 kb)
JPEG (27 kb)
Closure Phase vs Time
PS (52 kb)
JPEG 1		 Image with model components
PS (35 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)
0.420714 0.0815128 46.7528 0.184059 1.00000 0.00000 0.6060
(*) Quoted Brightness temperatures assume Gaussian components and are in the local (z=0) frame.


Last updated on Mon Nov 19 18:36:53 GMT 2001
by db_results.pl version 0.3.