Abstract
We describe the method of measurements and present the results obtained by optical spectroscopy for the excitation of valine molecules in the gas phase by collisions with low-energy electrons. Emission spectra of the excited molecules were measured in a wavelength interval of 260–440 nm upon excitation with electrons in the energy range of 10–70 eV. For the most intense spectral lines, optical functions of electron impact-induced excitation were measured in an energy range of 3–90 eV.