Spectra Properties:

Variable	Value
Prolongation method	Spectral
Shape of spectra region	Rectangle
Window function	Cosine

Everything else is default, see: ​page

Spectra Region

Following the wiki page on spectra objects, to calculate the spectra region in the simulation domain, you should compute the region in coarse cells first.

I took this to be a constant 40 pc (the diameter of the cylinder) in y & z, and adjusted the length in x to accommodate the shear angle + 10 pc on either side at its widest point:

Computing the number of coarse zones in this rectangular region gives,

Theta	Coarse Zones (Nx,Ny,Nz)
0	(13, 26, 26)
15	(20, 26, 26)
30	(28, 26, 26)
60	(58, 26, 26)