Abstract:
The disclosure relates to systems and methods for interleaving operation of a linear accelerator that use a magnetron as the source of electromagnetic waves for use in accelerating electrons to at least two different ranges of energies. The accelerated electrons can be used to generate x-rays of at least two different energy ranges. In certain embodiments, the accelerated electrons can be used to generate x-rays of at least two different energy ranges. The systems and methods are applicable to traveling wave linear accelerators.
Abstract:
A bipolar pulse forming transmission line module and system for linear induction accelerators having first, second, third, and fourth planar conductors which form a sequentially arranged interleaved stack having opposing first and second ends, with dielectric layers between the conductors. The first and second planar conductors are connected to each other at the first end, and the first and fourth planar conductors are connected to each other at the second end via a shorting plate. The third planar conductor is electrically connectable to a high voltage source, and an internal switch functions to short at the first end a high voltage from the third planar conductor to the fourth planar conductor to produce a bipolar pulse at the acceleration axis with a zero net time integral. Improved access to the switch is enabled by an aperture through the shorting plate and the proximity of the aperture to the switch.
Abstract:
An electromagnetic wave having a phase velocity and an amplitude is provided by an electromagnetic wave source to a traveling wave linear accelerator. The traveling wave linear accelerator generates a first output of electrons having a first energy by accelerating an electron beam using the electromagnetic wave. The first output of electrons can be contacted with a target to provide a first beam of x-rays. The electromagnetic wave can be modified by adjusting its amplitude and the phase velocity. The traveling wave linear accelerator then generates a second output of electrons having a second energy by accelerating an electron beam using the modified electromagnetic wave. The second output of electrons can be contacted with a target to provide a second beam of x-rays. A frequency controller can monitor the phase shift of the electromagnetic wave from the input to the output ends of the accelerator and can correct the phase shift of the electromagnetic wave based on the measured phase shift.
Abstract:
[PROBLEMS] To provide an induction voltage control device (8) capable of accelerating arbitrary charged particles to an arbitrary energy level in synchronization with any magnetic excitation pattern even for an acceleration voltage (9a) of constant voltage by an induction acceleration cell (6) for acceleration and its control method. [MEANS FOR SOLVING PROBLEMS] An induction voltage control device (8) includes: a digital signal processing device (8d) for controlling a variable delay time according to a necessary variable delay time pattern obtained based on a magnetic excitation pattern, an equivalent acceleration voltage value pattern, and a passing signal (7a) of a bunch (3) from a bunch monitor (7); and a pattern generator (8b) for conversion to a gate signal pattern (8a) of a switching power source (5b). The induction voltage control device (8) controls a pulse density of the induction voltage (9) for acceleration per control unit. A control method of the induction voltage control device is also disclosed.
Abstract:
A linac system having at least two linac structures configured to operate with a resonant coupler. The linac structures and the resonant coupler resonate at the same frequency, are in close proximity, and designed for a relative phase of 0° or 180°. The coupling between the resonant coupler and the linac structures is achieved by slots between the linac structures and the resonant coupler, which allow the magnetic fields of the linac structures to interact with the magnetic field of the resonant coupler. The relative size of the slots determines the relative amplitude of the fields in the linac structures. There are three modes of oscillation, a 0 mode, wherein the linac structures and the resonant coupler are excited in phase, a π/2 mode, wherein the linac structures are excited out of phase and the resonant coupler is nominally unexcited, and the π mode, wherein the linac structures and the resonator coupler are excited out of phase.
Abstract:
A bipolar pulse forming transmission line module and system for linear induction accelerators having first, second, third, and fourth planar conductors which form a sequentially arranged interleaved stack having opposing first and second ends, with dielectric layers between the conductors. The first and second planar conductors are connected to each other at the first end, and the first and fourth planar conductors are connected to each other at the second end via a shorting plate. The third planar conductor is electrically connectable to a high voltage source, and an internal switch functions to short at the first end a high voltage from the third planar conductor to the fourth planar conductor to produce a bipolar pulse at the acceleration axis with a zero net time integral. Improved access to the switch is enabled by an aperture through the shorting plate and the proximity of the aperture to the switch.
Abstract:
An electron beam accelerator system includes a high voltage supply circuit having a high voltage output. A cathode structure is coupled to the high voltage supply circuit at the high voltage output. An anode structure is spaced from the cathode structure and has a voltage associated therewith such that a voltage difference exists between the cathode structure and the anode structure. This voltage difference creates an electron beam flowing between the cathode structure and the anode structure. An electron beam output is adjacent to the anode structure. A control grid is located between the cathode structure and the anode structure and receives a time-varying voltage. This time-varying voltage prevents ringing of the high voltage output, reducing the risk of dielectric breakdown and failure due to transient high voltages.
Abstract:
A method and system for automatically conditioning a linear accelerator is disclosed. The method and system comprise the steps of measuring the global variables of the accelerator and evaluating a plurality of events based upon the measurement of the global variables in which the plurality of events have a hierarchy of importance. Finally, the method and system includes performing an action in response to the hierarchy of importance of the plurality of events. Accordingly, a system and method in accordance with the present invention allows an accelerator to be conditioned unattended. The system and method in accordance with the present invention combines software and hardware to measure global variables and modifies the condition of the accelerator based upon those variables. Through the use of a system and method in accordance with the present invention conditioning can proceed in small systematic steps, thereby resulting in better-conditioned accelerators. Accordingly, an improvement in both the performance and longevity of the accelerator will result due to the reduction in arcing and dark current. Additionally, a complete record of the conditioning process is automatically generated and archived with the attending benefit of quality control. Finally a significant savings in the overall costs will result from the utilization of a system and method in accordance with the present invention.
Abstract:
An electron beam accelerator system includes a high power switching device coupled between the direct current voltage source and the pulse forming network. A pulse control circuit is connected to control the high power switching device to selectively allow a current to flow to the pulse forming network. A voltage difference between a cathode and an anode structure creates an electron beam flowing therebetween. A control grid drive circuit is operatively coupled to the pulse control circuit and the control grid, and is operable to apply a time-varying voltage to the control grid synchronized with the pulse control circuit. The control grid therefore effectively provides a load on the high voltage output of a step-up transformer that prevents overshoot in the transformer output, reducing the risk of dielectric breakdown and failure due to transient high voltages.
Abstract:
A method for generating a closely spaced train of extremely high voltage short pulses. The method involves generating the train of pulses by combining a plurality of harmonic amplitudes to construct said pulses, via a Fourier construction. Any arbitrary pulse shape can be reproduced simply by changing the amplitude of the harmonics. The train of high voltage electrical pulses produced by the method of the present invention is particularly well suited for the acceleration of particles by applying the pulses to an appropriate accelerating structure, or the pulses can be used to drive an undulator/wiggler.