Summary of simulation plans
Dirk Petry (ESO/ARC), 23 March 2011
D. Petry, CASA Imaging – Testing – Simulation Plan Summary
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Imaging use cases
Structure
spectral
spatial
none
(flat)
powerlaw
continuum
single line
point source(s)
A1
vary a,b
B1
vary a,b,c
C1
vary a,b,c
barely resolved
(Gaussians)
A2
B2
vary a,b,c vary a,b,c
C2
vary a,b,c
general extended
(single field)
A3
vary b,c
B3
vary b,c
C3
vary b,c
general extended
(Mosaic)
A4
vary c
B4
vary c
C4
vary c
12 base cases
In addition vary
a) pos. w.r.t. phase center
b) dyn. range
c) uv coverage
general extended
(zero spacings)
D. Petry, CASA Imaging – Testing – Simulation Plan Summary
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Imaging use cases
Simulate in Band 6: 230 GHz, DEC = -30 deg, PWV = 1 mm, Tground = 270 K, Tsky = 260 K
a) pos. w.r.t. phase center
b) dyn. range
c) uv coverage
Structure
spectral
spatial
none
(flat)
point source(s)
A1
vary a,b
barely resolved
(Gaussians)
A2
vary a,b,c
general extended
(single field)
A3
vary b,c
general extended
(Mosaic)
A4
vary c
general extended
(zero spacings)
A1) keep one point source at center
This is always at 4 sigma of sensitivity
for given uv coverage
Second source is at phi = -45 deg,
r = 0.25, 0.5, 0.75 x 27.3 arcsecs,
intensity is 100, 1000, or 10000 x central source
uv coverage is 16 ants, 0.5 h
A2) like A1 w. Gaussians and 0.5+8 h, 16+40 ant, see B2
A3) keep ext object at center, dyn range and uv as in A2
A4) keep observed structure fixed, vary uv as in A2
Central source intensity = 4 x 0.07 mJy (0.5h ES), 4 x 0.017 mJy (8h ES),
4 x 0.022 mJy (0.5h 40 ants), 0.0055 mJy (8 h 40 ants)
Total datasets: 9 + 36 + 12 + 4 = 61
D. Petry, CASA Imaging – Testing – Simulation Plan Summary
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Imaging use cases
Simulate in Band 6: 230 GHz, DEC = -30 deg, PWV = 1 mm, Tground = 270 K, Tsky = 260 K
a) pos. w.r.t. phase center
b) dyn. range
c) uv coverage
Structure
spectral
spatial
powerlaw
continuum
point source(s)
B1
vary a,b,c
barely resolved
(Gaussians)
B2
vary a,b,c
general extended
(single field)
B3
vary b,c
general extended
(Mosaic)
B4
vary c
general extended
(zero spacings)
B1) keep one point source at center
This is always at 4 sigma of sensitivity
for given uv coverage (as in A)
Second source is at phi = -45 deg,
r = 0.25, 0.5, 0.75 x 27.3 arcsecs,
intensity is 100, 1000, or 10000 x central source
uv coverages: 0.5+8 h, 16 + 40 ants
2 Spectral indices = typical (2) and steep (4)
B2) like B1 but with Gaussians of sigma = 2.5 sigma SB
B3) keep ext object at center, dyn range and uv as in B2
B4) keep observed structure fixed, vary uv as in B2
Intensities t.b.d., want 4 sigma in faintest chan.
Total datasets: 72 + 72 + 12 + 4 = 160
D. Petry, CASA Imaging – Testing – Simulation Plan Summary
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Imaging use cases
Simulate in Band 6: 230 GHz, DEC = -30 deg, PWV = 1 mm, Tground = 270 K, Tsky = 260 K
a) pos. w.r.t. phase center
b) dyn. range
c) uv coverage
Structure
spectral single line
spatial
point source(s)
C1
vary a,b,c
barely resolved
(Gaussians)
C2
vary a,b,c
general extended
(single field)
C3
vary b,c
general extended
(Mosaic)
C4
vary c
general extended
(zero spacings)
C1) keep one point source at center
This is always at 4 sigma of sensitivity
for given uv coverage (as in A)
Second source is at phi = -45 deg,
r = 0.25, 0.5, 0.75 x 22.4 arcsecs,
intensity is 100, 1000, or 10000 x central source
uv coverage is 0.5 and 8 h, 16 and 40 ants
100 channels, 2 Line shapes: 3 or 25 chan. FWHM
C2) like C1 but use Gaussians as in B2
C3) keep ext object at center, dyn range and uv as in C2
C4) keep observed structure fixed, vary uv as in C2
Intensities t.b.d., want 4 sigma at HM.
Total datasets: 72 + 72 + 12 + 4 = 160
D. Petry, CASA Imaging – Testing – Simulation Plan Summary
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Imaging use cases
Structure
spectral
spatial
none
(flat)
powerlaw
continuum
single line
point source(s)
A1
vary a,b
B1
vary a,b,c
C1
vary a,b,c
barely resolved
(Gaussians)
A2
B2
vary a,b,c vary a,b,c
C2
vary a,b,c
general extended
(single field)
A3
vary b,c
B3
vary b,c
C3
vary b,c
general extended
(Mosaic)
A4
vary c
B4
vary c
C4
vary c
general extended
(zero spacings)
12 base cases
In addition vary
a) pos. w.r.t. phase center
b) dyn. range
c) uv coverage
Total of
61 + 160 + 160 = 441 cases
Naming scheme for MeasurementSets:
imtest-<basecase>-a<offset_arcs>-<posang_deg>-b<dynrange>-c<obstime-nant>-<user>.ms
e.g. imtest-A2-a20-45-b100-c0.5h-16-longmore.ms
D. Petry, CASA Imaging – Testing – Simulation Plan Summary
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Open issues:
- Select spectral indices for Bx: 2 and 4
- sigma of Gaussians for x2: 2.5 sigma of Synth. Beam
- details of spectral setup for Ax and Bx: do typical continuum setup: 8 GHz, 512 ch.
- Intensities for Bx: Luca
- Intensities for Cx: Pam
- resolution of the input image: high-res., i.e. factor 10 better than small SB, i.e. 0.01”
- generation of reference images: regrid input images to output images
- can we actually generate and store the 441 cases?
-> need to generate one of the 512 channel cubes to see …
D. Petry, CASA Imaging – Testing – Simulation Plan Summary
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