The four peak parameters are “position” with the peak position as either \(2\theta \) (degrees) or TOF (\(\mu \)sec), “intensity” which is the integrated intensity for the peak on the intensity scale of the diffraction pattern. The “sigma\({}^2\)” and “gamma” values are the Gaussian and Lorentzian peak widths, respectively. Note that the Gaussian full-width at half-maximum (\(FWHM_G\)) is related to “sigma\({}^2\)” (\(\sigma ^2\)), which is the peak variance, by:
\[FWHM_G = \sqrt {8 * \ln 2 * \sigma ^ 2}\]
while the Lorentzian full-width at half-maximum (\(FWHM_L\)) is just “gamma” (\(\Gamma \)):
\[FWHM_L = \Gamma \]
The \(sigma^2\) values are in units of centidegrees\(^2\) (centidegrees are degrees \(\times 100\)) for CW data or microseconds\({}^2\) for TOF data; \(\Gamma \) has units of centidegrees or microseconds.