The profile radius (intrinsic excitation-error width = mosaicity + divergence)
was the plain RMS of dist_ewald over indexed spots. With a finite energy
bandwidth that spread is broadened by the bandwidth's radial smear
sigma_bw = bandwidth_sigma*lambda/(2 d^2), which prediction then re-applies per
reflection - so bandwidth was counted twice and the radius was inflated (most at
high resolution, sigma_bw ~ 1/d^2). Subtract the bandwidth variance from the
measured spread so the radius is the intrinsic width. bandwidth = 0
(monochromatic / rotation) is unchanged. Small for narrow bandwidths (~6% of the
variance, ~4% radius on the 1% jet); matters for wide-bandwidth / pink beam.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
leonarski_fandClaude Opus 4.8
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