High Efficiency Compact High Voltage Vector Inversion Generators
Vector Inversion Generators, VIG, were invented by Fitch and Howell1. The spiral-line VIG takes electrostatically stored energy and converts it into a fast rising high voltage pulse in a dynamic two component, one-step process. We present the results for a variety of units operating over a wide range of parameters. The highest voltage achieved in a single ultra-compact unit has been 500 kV in a device that is 8 inches long and 5 inches in diameter. Two of these units have been operated in tandem to produce a 1 MV pulse generator that failed after about 10 cycles. Finally, we discuss the range of loads that can be driven by this dynamic device in terms of the VIG dynamics and the RC time constant for the load.
High voltage solid state switched Vector Inversion Generators
A Vector Inversion Generator, VIG, consists of two parallel plate transmission lines sharing a common conductor wound on a mandrel. By simple switching of one of the lines, it is possible to take statically stored energy and convert it to a transient high voltage electromagnetic pulse in a one step process. These units can be made highly efficient and are capable of developing high transient voltages in a time that is determined by the two way transit time for an electromagnetic wave to propagate up the active line. Heretofore, the active line in a VIG has been switched using a dielectric puncture or by a spark gap due to the high currents and time rate of change of current. In this paper, we will describe our efforts to produce a solid state, precision switched VIG for applications at high repetition rate and at modest energy per pulse. Test data at repetition rates (rep-rates) up to 500 Hz and for modest voltages will be presented.
Resonant Auger decay study of C1s -> pi* core-excited OCS
The present work aims at characterizing short-lived C1s((-1)) pi*((1)) core-excited states of the OCS molecule based on the analysis of the vibrational fine structure and lineshape profiles of the high-resolution resonant Auger decay spectra recorded at the excitation energies along the C1s -> pi* resonance in the binding energy region 15-19eV. Very different behavior in terms of lineshape and resonant enhancement is observed for the (A) over tilde, (B) over tilde and (C) over tilde final states. This is explained by (1) the variation in the C-O bond lengths for the states involved in the electronic relaxation and (2) different contributions in terms of Mulliken population to the molecular orbitals determining the electronic character of the corresponding states. Since the final-state geometries are known from a number of previous experiments and ab initio calculations, the geometry of the C1s((-1)) pi*((1)) intermediate states can be predicted in analogy with e.g. the N-2, CO2 and N2O molecules. (C) 2009 Elsevier B.V. All rights reserved. (Less)