Stephen Bourke - Challenge 7

Stephen Bourke - Challenge 7

Polarised Source II

Logged on 08/24/2009 05:40:44 PM

This time the source is linearly polarised with an angle or 45'. I = 10Jy, U = 10Jy

MS Simulation

Logged on 08/24/2009 05:52:09 PM

The MS was simulated as in the previous challenge, and a dirty image was generated. The source can be seen in stokes I and U. Q and V contain an image which looks similar to when the model was subtracted from uncalibrated data in challenge 1. This makes sense since Q and V are related to the difference of the X and Y feeds.

Data products

SSSC7_WSRT.MS.DATA.channel.1ch.fits (header)

1x4x512x512 FITS cube, 4 planes are given below.

0-full.png

Image plane #0.

data range:-0.204159,4.99845
mean:-0.00596457
sigma:0.122857
clipping:95%
clip range:-0.204159,0.212457
1-full.png

Image plane #1.

data range:-0.0499474,0.0321995
mean:-0.000201478
sigma:0.00831869
clipping:95%
clip range:-0.0163345,0.0155134
2-full.png

Image plane #2.

data range:-0.205045,4.99679
mean:-0.0058132
sigma:0.12278
clipping:95%
clip range:-0.205045,0.211509
3-full.png

Image plane #3.

data range:-0.0246787,0.0246787
mean:-1.49998e-07
sigma:0.00460876
clipping:95%
clip range:-0.00949551,0.00954371

Source Subtraction

Logged on 08/24/2009 05:55:36 PM

Subtracting the model from the uncalibrated data gives the expected results. This time however the artifacts are visible in all stokes.

Data products

SSSC7_WSRT.MS.CORRECTED_DATA.channel.1ch.fits (header)

1x4x512x512 FITS cube, 4 planes are given below.

0-full.png

Image plane #0.

data range:-0.027363,0.0720199
mean:0.000128688
sigma:0.00811996
clipping:95%
clip range:-0.0161048,0.0146612
1-full.png

Image plane #1.

data range:-0.0498482,0.032199
mean:-0.000199748
sigma:0.00834612
clipping:95%
clip range:-0.0167569,0.0153729
2-full.png

Image plane #2.

data range:-0.0289559,0.0728483
mean:0.000167938
sigma:0.00813648
clipping:95%
clip range:-0.0134466,0.0190631
3-full.png

Image plane #3.

data range:-0.0246792,0.0246792
mean:-2.1171e-09
sigma:0.00456789
clipping:95%
clip range:-0.00944752,0.00939932

Calibration

Logged on 08/24/2009 06:04:15 PM

Calibrating using G Jones yields good residual images.

Data products

SSSC7_WSRT.MS.CORRECTED_DATA.channel.1ch.fits (header)

1x4x512x512 FITS cube, 4 planes are given below.

0-full.png

Image plane #0.

data range:-1.5267e-09,1.70606e-09
mean:-2.69375e-12
sigma:3.98883e-10
clipping:95%
clip range:-8.4163e-10,7.33706e-10
1-full.png

Image plane #1.

data range:-1.85577e-09,2.19367e-09
mean:2.30888e-12
sigma:4.00406e-10
clipping:95%
clip range:-9.06685e-10,7.10719e-10
2-full.png

Image plane #2.

data range:-1.6928e-09,1.65555e-09
mean:2.37765e-11
sigma:4.14979e-10
clipping:95%
clip range:-8.36095e-10,8.08651e-10
3-full.png

Image plane #3.

data range:-1.72813e-09,1.72813e-09
mean:6.87852e-17
sigma:4.06587e-10
clipping:95%
clip range:-8.91068e-10,7.39181e-10
This log was generated by PURR version 1.0.