LINE BY LINE CALCULATION OF SPECTRA FROM DIATOMIC MOLECULES AND ATOMS ASSUMING A VOIGT LINE PROFILE

A computer program is described that predicts the spectra resulting from electronic transitions of diatomic molecules and atoms. The program produces a spectrum by accounting for the contributions from all the individual rotational and atomic lines considered in the calculations. The integrated intensity of each line is distributed in the spectrum by an approximate Voigt profile. The program can produce spectra for either optically thin gases or for cases where simultaneous emission and absorption occur. The method allows calculations ranging from the absorption of incident radiation by a column of cold gas to the high temperature self-absorbed emission spectrum from a nonisothermal gas. The computed spectrum can be output directly and, if desired, the predicted output of a grating spectrograph or a fixed wavelength radiometer can be generated, including instrumental broadening and sensitivity. Several examples illustrating the versatility of the program are presented. Information is given which will enable the reader to acquire a copy of the program and a paper containing instructions for its usage. © 1969.