2.3.2.0 vpmanager.setpbairy

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vpmanager.setpbairy - Function

2.3.2 Make an airy disk vp

Description

Information sufficient to create a portion of the Airy disk voltage pattern. The Airy disk pattern is formed by Fourier transforming a uniformly illuminated aperture and is given by

vpp(i) = (areaRatio*2.0*j1(x)∕x- 2.0*j1(x *lengthRatio)∕(x*lengthRatio))∕areaN orm,

(2.10)

where areaRatio is the dish area divided by the blockage area, lengthRatio is the dish diameter divided by the blockage diameter, and

x = i*maxrad-*-7.016*-dishdiam-∕24.5m-. Nsamples * 1.566* 60

(2.11)

Arguments


Inputs
telescope	Which telescope in the MS will use this vp/pb?
	allowed:	string
	Default:	VLA
othertelescope	If telescope==”OTHER”, specify name here
	allowed:	string
	Default:
dopb	Should we apply the vp/pb to this telescope’s data?
	allowed:	bool
	Default:	true
dishdiam	Effective diameter of dish
	allowed:	any
	Default:	variant 25.0m
blockagediam	Effective diameter of subreflector blockage
	allowed:	any
	Default:	variant 2.5m
maxrad	Maximum radial extent of the vp/pb (scales with 1/freq)
	allowed:	any
	Default:	variant 0.8deg
reffreq	Frequency at which maxrad is specified
	allowed:	any
	Default:	variant 1.0GHz
squintdir	Offset (Measure) of RR beam from pointing center, azel frame (scales with 1/freq)
	allowed:	any
	Default:	variant
squintreffreq	Frequency at which the squint is specified
	allowed:	any
	Default:	variant 1.0GHz
dosquint	Enable the natural beam squint found in the common vp model
	allowed:	bool
	Default:	false
paincrement	Increment in Parallactic Angle for asymmetric (ie, squinted) vp application
	allowed:	any
	Default:	variant 720deg
usesymmetricbeam	Not currently used
	allowed:	bool
	Default:	false

Returns
record
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