Wien peaks and the Lambert W function

exact expressions for the wavelengths where maxima occur in the spectral distribution curves of blackbody radiation for a number of diferent dispersion rules are given in terms of the lambert w function. these dispersion rule dependent "wien peaks" are compared to those wavelengths obtained in a setting independent of the dispersion rule chosen where the "peak" wavelengths are taken to be those obtained on dividing the total radiation intensity emitted from a blackbody into a given percentile. the account provides a simple yet accessible example of the growing applicability of the lambert w function in physics.