• The finite width of histogram bins will always be taken into account precisely.
• Need a lineshape? Skewed Gaussian? Skewed Gaussian with a low-energy shoulder to account for Compton scattering? You want it, you got it.
• Regardless of shape, peaks will be properly normalized forevermore.
• Need to calibrate energy? Fix relative intensities and fit centroids.
• Need to calibrate efficiency? Fix centroids and fit relative intensities.
• Need to calculate the errors on the fit parameters, including correlations, precisely? No problem!