This award will support collaborative research between Prof. Jacob Leventhal of the University of Missouri at St. Louis and Dr. Maria Allegrini of the Istituto di Fisica Atomica e Molecolare (CNR) in Pisa together with Prof. Ennio Arimondo of the University of Pisa, Italy. The researchers' previous collaborative work has focused on experimental studies of the properties of Rydberg atoms. The next phase is directed towards the study of photoionization of Rydberg atoms, first by blackbody radiation and later, after reducing the ambient temperature to approximately 15 K, by far infrared radiation from an alcohol laser. The importance of highly excited (Rydberg) atoms in a variety of physical phenomena has been recognized since 1934. Recent interest in applications such as isotope separation, thermonuclear fusion and astrophysical plasmas, coupled with the availability of tunable lasers to produce state selected Rydberg atoms has led to much activity in this area. The proposed work of the researchers, building on previous successful collaboration, is designed to take advantage of experimental techniques developed both at the University of Missouri-St. Louis and in Pisa. The group at St. Louis has considerable experience with visible lasers and the production of highly excited atoms, whereas the group in Pisa has extensive experience with the long wavelength lasers necessary to study photoionization of Rydberg atoms. Consequently, their complementary expertise should prove mutually beneficial and help to advance our knowledge in this area.
