Challenge 6

Challenge 6

Polarised Source

Logged on 08/24/2009 03:14:09 PM

The source is simulated again but this time it is fully linearly polarised I = 10Jy, Q = 10Jy.

MS simulation

Logged on 08/24/2009 03:25:01 PM

The MS was simulated as in Challenge 1. A dirty image was generated, this time all 4 stokes were imaged and the image is visible in I and Q. U and V are blank meaning that there is no polarisation leakage.

Data products

SSSC6_WSRT.MS.DATA.channel.1ch.fits (header)

1x4x512x512 FITS cube, 4 planes are given below.

0-full.png

Image plane #0.

data range:-0.198725,4.98532
mean:-0.0061613
sigma:0.122663
clipping:95%
clip range:-0.198725,0.211341
1-full.png

Image plane #1.

data range:-0.198725,4.98532
mean:-0.0061613
sigma:0.122663
clipping:95%
clip range:-0.198725,0.211341
2-full.png

Image plane #2.

data range:0,0
mean:0
sigma:0
clipping:95%
clip range:0,0.000976562
3-full.png

Image plane #3.

data range:0,0
mean:0
sigma:0
clipping:95%
clip range:0,0.000976562

Source subtraction

Logged on 08/24/2009 04:23:56 PM

Subtracting the model from the uncalibrated data shows similar artifacts to in Challenge 1.

Data products

SSSC6_WSRT.MS.CORRECTED_DATA.channel.1ch.fits (header)

1x4x512x512 FITS cube, 4 planes are given below.

0-full.png

Image plane #0.

data range:-0.0394247,0.0384209
mean:-4.3749e-06
sigma:0.0086497
clipping:95%
clip range:-0.0185189,0.0162228
1-full.png

Image plane #1.

data range:-0.0394247,0.0384209
mean:-4.3749e-06
sigma:0.0086497
clipping:95%
clip range:-0.0185189,0.0162228
2-full.png

Image plane #2.

data range:0,0
mean:0
sigma:0
clipping:95%
clip range:0,0.000976562
3-full.png

Image plane #3.

data range:0,0
mean:0
sigma:0
clipping:95%
clip range:0,0.000976562

Calibration

Logged on 08/24/2009 04:30:26 PM

'Calibrate' and 'Correct data or residuals' as well as G Jones were selected in the TDL options and recompiled. The G diagonal terms were then calibrated and a residual image made. The residual image has a very low noise level, and the amplitudes are flat in the Corrected_data column. There does seem to be some artifact present however - a quite large almost horizontal ripple...

Data products

SSSC6_WSRT.MS.CORRECTED_DATA.channel.1ch.fits (header)

1x4x512x512 FITS cube, 4 planes are given below.

0-full.png

Image plane #0.

data range:-2.39581e-09,2.90326e-09
mean:4.52504e-12
sigma:5.71658e-10
clipping:95%
clip range:-1.12279e-09,1.14897e-09
1-full.png

Image plane #1.

data range:-2.39581e-09,2.90326e-09
mean:4.52504e-12
sigma:5.71658e-10
clipping:95%
clip range:-1.12279e-09,1.14897e-09
2-full.png

Image plane #2.

data range:0,0
mean:0
sigma:0
clipping:95%
clip range:0,0.000976562
3-full.png

Image plane #3.

data range:0,0
mean:0
sigma:0
clipping:95%
clip range:0,0.000976562
inspector:input_data_0_1.png

inspector:input_data_0_1.png
This log was generated by PURR version 1.0.