LASER-ENHANCED IONIZATION SPECTROSCOPY OF MERCURY RYDBERG STATES

The spectral characteristics of mercury Rydberg states (n = 10-42) wer e observed and studied. Each principal quantum number was observed as a tripler, and after observing a quarter of lines for n = 10, 11, and 12, these lines were assigned, from red to blue, as belonging to upper levels P-1(1)0, P-3(2)0, P-3(1)0, and P-3(0)0. These levels were stud ied as a function of variable applied high voltage (between the electr odes) and variable buffer gas pressure. In this way, the broadening an d splitting caused by the influence of Stark effects and of increasing buffer gas pressure were observed for different n values. These obser vations will allow one to choose the optimal level for excitation, as well as the optimal operating conditions in terms of pressure and appl ied high voltage, for obtaining the best sensitivity and limit of dete ction by analytical laser-enhanced ionization spectroscopy. (C) 1997 E lsevier Science B.V.