Measurements of the Non-Linear Coupling of Plasma Waves

POSTER

Abstract

A separatrix is created in a pure electron plasma column by applying a $\theta$-symmetric wall voltage. This ``squeeze'' voltage traps less energetic electrons in either end and allows more energetic electrons to pass through. These trapped particles enable the novel Trapped Particle Diocotron Mode (TPDM). We excite an ordinary $m=2$ diocotron mode at frequency $f_2$ to amplitude $A_2$ and observe the decay into the $m=1$ TPDM at $f_1 \approx f_2 / 2$. The exponential growth rate, $\Gamma$, of the TPDM is obtained as a function of the amplitude $A_2$ as well as a function of the ``squeeze'' voltage which determines the frequency mismatch $\delta f = f_2 / 2 - f_1$. We calibrate the amplitudes of the modes in terms of the received wall voltages, and obtain a quantitative value of the non-linear coupling coefficient, $V$. These results at $B = 280$~G will be compared to recent results\footnote{A.A. Kabantsev, T.M. O'Neil, Yu.A. Tsidulko, and C.F. Driscoll, Phys.~Rev.~Lett. {\bf 101}, 065002 (2008).} from a separate apparatus at $B > 2000$~G.

Authors

  • E.K. Snipes

    Wittenberg University

  • Doug Petkie

    AFRL/RX, AFRL/RX, Systran Systems Inc, UCSD, Los Alamos National Laboratory, Ohio Northern University, BFS, Germany, Florida State University, Monmouth College, Ohio Wesleyan University, Department of Chemical and Biomolecular Engineering, The University of Akron, Physics Department, John Carroll University, Department of Chemistry, Knight Chemical Laboratories, The University of Akron, Australian National University, Miami University, Oxford, OH, University of Cincinnati, University of Findlay, Naval Research Laboratory, Washington, DC 20375, Cleveland State University, Health Sciences Dept, Cleveland State University, Physics Dept, Cleveland State University, Bucknell University, Wright State University, Air Force Research Laboratory, Materials and Manufacturing Directorate, Wright-Patterson AFB, Wright State University, Department of Physics, University of Puerto Rico, Department of Mechanical Engineer, Air Force Research Laboratory, Materials and Manufacturing Directorate, Wright-Patterson AFB and UES, Inc., Department of Environmental Science and Policy, School of Science, Marist College, Poughkeepsie, NY 12601, USA, AFRL/711 HPW, EPA Sustainable Technology Division, University of Akron, Rose-Hulman Institute of Technology, Harvard University, LSU, Ohio University, Wittenberg University, Student

  • Doug Petkie

    AFRL/RX, AFRL/RX, Systran Systems Inc, UCSD, Los Alamos National Laboratory, Ohio Northern University, BFS, Germany, Florida State University, Monmouth College, Ohio Wesleyan University, Department of Chemical and Biomolecular Engineering, The University of Akron, Physics Department, John Carroll University, Department of Chemistry, Knight Chemical Laboratories, The University of Akron, Australian National University, Miami University, Oxford, OH, University of Cincinnati, University of Findlay, Naval Research Laboratory, Washington, DC 20375, Cleveland State University, Health Sciences Dept, Cleveland State University, Physics Dept, Cleveland State University, Bucknell University, Wright State University, Air Force Research Laboratory, Materials and Manufacturing Directorate, Wright-Patterson AFB, Wright State University, Department of Physics, University of Puerto Rico, Department of Mechanical Engineer, Air Force Research Laboratory, Materials and Manufacturing Directorate, Wright-Patterson AFB and UES, Inc., Department of Environmental Science and Policy, School of Science, Marist College, Poughkeepsie, NY 12601, USA, AFRL/711 HPW, EPA Sustainable Technology Division, University of Akron, Rose-Hulman Institute of Technology, Harvard University, LSU, Ohio University, Wittenberg University, Student

  • Doug Petkie

    AFRL/RX, AFRL/RX, Systran Systems Inc, UCSD, Los Alamos National Laboratory, Ohio Northern University, BFS, Germany, Florida State University, Monmouth College, Ohio Wesleyan University, Department of Chemical and Biomolecular Engineering, The University of Akron, Physics Department, John Carroll University, Department of Chemistry, Knight Chemical Laboratories, The University of Akron, Australian National University, Miami University, Oxford, OH, University of Cincinnati, University of Findlay, Naval Research Laboratory, Washington, DC 20375, Cleveland State University, Health Sciences Dept, Cleveland State University, Physics Dept, Cleveland State University, Bucknell University, Wright State University, Air Force Research Laboratory, Materials and Manufacturing Directorate, Wright-Patterson AFB, Wright State University, Department of Physics, University of Puerto Rico, Department of Mechanical Engineer, Air Force Research Laboratory, Materials and Manufacturing Directorate, Wright-Patterson AFB and UES, Inc., Department of Environmental Science and Policy, School of Science, Marist College, Poughkeepsie, NY 12601, USA, AFRL/711 HPW, EPA Sustainable Technology Division, University of Akron, Rose-Hulman Institute of Technology, Harvard University, LSU, Ohio University, Wittenberg University, Student

  • C.F. Driscoll

    UCSD