Beam-Wave Research, Inc., Union City
SAIC, Burlington, Massachusetts
NRL, Washington, DC
STAAR/AWR Corporation, Mequon
Funding: Research funded by the Office of Naval Research and Naval Research Laboratory.
The accelerator community is making the transition to IOT technology for a number of high-power UHF and L-band applications as a result their inherent benefits. Scientists, funded by the Office of Naval Research and Naval Research Laboratory, are investigating the physics of the beam-wave interaction of the IOT. The time-domain electrostatic PIC code MICHELLE, in conjunction with the Analyst® suite of electromagnetic codes, were used to model the cathode-grid-anode structure that comprise the input cavity. Our investigation has led to the discovery of a delay mechanism responsible for intra-bunch charge formation, as evidenced by IOT X-ray generation with energies significantly higher than the cathode accelerating potential, increasing with RF output power. Time-domain PIC results of this effect will be shown. We will also present simulation results of the large-signal beam wave interaction in the output cavity using the code TESLA. Examples of single beam and multiple-beam IOTs will also be shown.
INFN/LNF, Frascati (Roma)
STAAR/AWR Corporation, Mequon
SLAC, Menlo Park, California
CERN, Geneva
To suppress the vertical beam instability in the CTF3 Combiner Ring caused by vertical trapped modes in the rf deflectors, two new devices have been constructed. In the new structures special antennas absorb the power released by the beam to the modes. They have been realized in aluminium to reduce the costs and delivery time and have been successfully installed in the ring. In the paper we illustrate the electromagnetic design, the realization procedures, the rf measurement and high power test results.
G.H. Gillespie Associates, Inc., Del Mar, California
STAAR/AWR Corporation, Mequon
Funding: Work at G. H. Gillespie Associates, Inc. funded by the U.S. Department of Energy SBIR grant number DE-FG02-05ER84360
An automated procedure for the calculation of particle transfer maps using computed magnetic field data has been developed for several types of magnetic quadrupoles. The Automated Transfer Map Generator (ATMG) software used for these calculations combines the Analyst program and specialized modules of the Particle Beam Optics Laboratory (PBO Lab). Analyst's scripted solids capability is used to develop models of different magnet concepts. The geometry and material attributes for a given magnet concept are encapsulated by a small number of magnet parameters. Quadrupoles of the same basic concept can be simulated by using different values for the magnet parameters. The three-dimensional magnetic field solver (MS3p) of the Analyst program is used to obtain the fields. New PBO Lab modules are used to automate the field computation, and then calculate the transfer maps and matrices through third-order using the Venturini-Dragt method. Examples for three different types of magnetic quadrupole lenses are presented: electromagnetic air-core, electromagnetic iron-core, and rare-earth permanent magnet quadrupoles.