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Auto-generated documentation for class RadialBkgd

Initialization

    from pyimgalgos.RadialBkgd import RadialBkgd
    rb = RadialBkgd(xarr, yarr, mask=None, radedges=None, nradbins=100, phiedges=(0,360), nphibins=32)

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Input per-pixel coordinates passed in numpy arrays xarr, yarr are used to evaluate per-pixel radius and polar angle:

rad = rb.pixel_rad()
phi = rb.pixel_phi()

Binning parameters radedges, nradbins, phiedges, nphibins are used to initialize 2-d bins using class HBins. Initialization with default binning parameters covers entire detector coordinate space.

Non-default binning, for example like

   rb rbkg = RadialBkgd(X, Y, mask, nradbins=3, nphibins=8, phiedges=(-20, 240), radedges=(10000,80000))

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and gives 3 bins in radial direction from 10mm to 80mm and 8 bins in angle from -20 to 240 degree:

irad = rb.pixel_irad()
iphi = rb.pixel_iphi()
iseq = rb.pixel_iseq()

Pixels masked by the n-d array passed in the parameter mask are excluded from this algorithm and are not corrected.

Averaged background intensity for default and non-default binning cases (nphibins=8, nradbins=500):

bkgd = rb.bkgd_nda(nda)

Results

Background subtracted data for default (nradbins=100, nphibins=32) and non-default binning cases (nradbins=500, nphibins=1), and (nradbins=500, nphibins=8, phiedges=(-20, 240)): 

res = rb.subtract_bkgd(nda)

• For good statistical background averaging 2-d bins should contain large number of pixels. Binning artifact in some places are seen in resulting image.
• Photon beam polarization effect is observed in the image with single angular bin (ring-shaped radial bins). One could eliminate this effect by modulation of the background sample using polarization correction.

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References

• Auto-generated documentation for class RadialBkgd
• Auto-generated documentation for class HBins

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