SPECPR Users’ Manual Page 8-f6.1 F6: Black Body Computation Alias: plan[ck] This function computes the Planck black body function at a given temperature (in degrees Kelvin) and any wavelength set. Currently, the output is in watts per square meter per micron per steradian and the input wavelength set is assumed to be in microns. Upon entering the routine, you are asked to type in the temperature and the wavelength id and record number. When using extreme temperatures or extreme wavelengths, you should check the results for underflow or overflow in the CRT plot routines (Chapter 9). No file or errors are needed since this routine generates a new file instead of an operation on an old one. The equation used is HTML-IMAGEcpile { E sub i (T) ={ 8 pi h c sup 2 } over { lambda sup 5 } left [ e sup {{ h c} over { lambda k T }} - 1 right ] sup -1 above ={ 1.4966 times 10 sup -5 } over lambda sup -5 left [ e sup {13586 over { lambda T } } -1 right ] sup -1 } HTML-IMAGE-END where E is the energy for each channel at wavelength, λ (in microns), T is the temperature (degrees Kelvin), c is the speed of light, h is the Planck constant (= 6.6252×10-34 Joule-seconds), and k is the Boltzmann constant (= 1.3806×10-23 Joule/°K).