Study of Odd-Parity Autoionization States of Praseodymium Atom
by Optogalvanic Spectroscopy

Abstract

Autoionization states of neutral praseodymium atom (Pr I) were investigated using two-color two-step laser resonance ionization spectroscopy (RIS). A Pr hollow cathode lamp was used as an atomic source and optogalvanic signals were measured. The Pr I was excited from the ground state to four first step excitation levels (21120.69, 21471.81, 22014.11 and 23067.34 cm^-1) by the first step laser. These four channels were used to study odd-parity autoionization states. Four dyes were used in the second step excitation. The 108 odd-parity autoionization states were found by optogalvanic spectroscopy and their total angular momentum (J) values were estimated.