Dr. Marianne BreinigProfessor
Ph.D., University of Oregon, 1979
Office: 202 Nielsen Physics Building
Electron emission in fast ion-atom collisionsIonizing collisions between ions, atoms, and molecules are fundamental processes of nature, which are of basic interest, and which play an important role in such diverse fields as fusion energy, atmospheric and astrophysical sciences, nuclear waste management, radiation biology, medicine et cetera. In fast ion-atom collisions projectile and target excitation and ionization and target-electron transfer into bound or continuum states of the projectile are all possible, and often many of these processes occur in the same collision. The emission of electrons into the continuum in fast ion-atom collisions has been the focus of many investigations, since the energy and angular distributions of the ejected electrons carry valuable information about the ionizing mechanisms and the structure of the collision partners.
My current research is part of a larger effort to measure the total recoil-ion charge-state resolved energy and angular distribution of electrons ejected into the continuum in fast ion-atom collisions. Two new spectrometer systems have been designed and built to allow measurements of the energy and angular distribution of ejected electrons over nearly their entire energy range and over a wide angular range. Electrons are detected in coincidence with the exit charge state of the projectile ion or with the charge state of the target recoil ion. We make our measurement using the EN Tandem Van de Graaff accelerator located at the Oak Ridge National Laboratory.
In our recent experiments we investigate a prominent feature in the electron energy distributions, the binary-encounter peak. Experimental results are compared with binary-encounter electron production cross sections obtained using the impulse approximation and with theoretical predictions from many-body classical trajectory Monte-Carlo calculations.
Brief VitaProfessor Marianne Breinig was certified as a teacher of mathematics and physics by the J. W. Goethe Universitšt, Frankfurt, Germany in 1972. In 1975 she received a M. A. and in 1979 a Ph.D. in Physics from the University of Oregon. After two years as a Postdoctdoctoral Research Associate she joined the faculty at the University of Tennessee in 1981. Since 1988 she also holds a position as Adjunct R and D Participant in the Physics Division of the Oak Ridge National Laboratory. She focuses her efforts in the areas of Atomic Collision Physics and Physics Teaching and Instructional Technology.