ess.powder.correction.apply_lorentz_correction#

ess.powder.correction.apply_lorentz_correction(da)[source]#

Perform a Lorentz correction for ToF powder diffraction data.

This function uses this definition:

\[L = d^4 \sin\theta\]

where \(d\) is d-spacing, \(\theta\) is half the scattering angle (note the definitions in https://scipp.github.io/scippneutron/user-guide/coordinate-transformations.html).

The Lorentz factor as defined here is suitable for correcting time-of-flight data expressed in wavelength or d-spacing. It follows the definition used by GSAS-II, see page 140 of https://subversion.xray.aps.anl.gov/EXPGUI/gsas/all/GSAS%20Manual.pdf

Parameters:

da (DataArray) – Input data with coordinates two_theta and dspacing.

Returns:

DataArrayda multiplied by \(L\). Has the same dtype as da.