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Principal diagnostics systems have been installed and nearly all have been commissioned on the subsystems of the Advanced Photon Source (APS) facility. Data have been obtained on beam position, beam profile, current, beam loss rat...
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Principal diagnostics systems have been installed and nearly all have been commissioned on the subsystems of the Advanced Photon Source (APS) facility. Data have been obtained on beam position, beam profile, current, beam loss rate, and synchrotron radiation monitors on both injector rings and most recently the main 7-GeV storage ring. Results for the 150- to 450-MeV electron beams in the accumulator ring, up to 7 GeV in the injector synchrotron, and 4.5 to 7 GeV in the SR will be presented.
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A high beam power in the proposed Fermilab Proton Drivers--1.2 MW in 16-GeV PD-I and 0.48 MW in 8-GeV PD-II--implies serious constraints on beam losses in these machines. Only with a very efficient beam collimation system can one ...
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A high beam power in the proposed Fermilab Proton Drivers--1.2 MW in 16-GeV PD-I and 0.48 MW in 8-GeV PD-II--implies serious constraints on beam losses in these machines. Only with a very efficient beam collimation system can one reduce uncontrolled beam losses in the machine to an allowable level. The entire complex must be well shielded to allow acceptable hands-on maintenance conditions in the tunnel and a non-controlled access to the outside shielding at normal operation and accidental beam loss. Collimation and shielding performances are calculated and compared for both Proton Drivers.
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Normal form analysis and tracking results show that both normal and skew211 resonances are driven strongly by the non-linear fields of the IR quadrupoles. We 211 report here on the possibility of improving the dynamic aperture by ...
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Normal form analysis and tracking results show that both normal and skew211 resonances are driven strongly by the non-linear fields of the IR quadrupoles. We 211 report here on the possibility of improving the dynamic aperture by compensating 211 these resonances with the use of correctors placed in the IRs. The effectiveness 211 of local correction schemes in the presence of beam-beam interactions is also 211 studied.
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The Amsterdam Pulse Stretcher (AmPS) was equipped with 16 viewscreens, whichinterfere strongly with the beam. In order to reach the stage where an attempt can be made to correct the machine closed orbit, the beam should travel for...
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The Amsterdam Pulse Stretcher (AmPS) was equipped with 16 viewscreens, whichinterfere strongly with the beam. In order to reach the stage where an attempt can be made to correct the machine closed orbit, the beam should travel for at least one turn around the machine. To do so, AmPS is considered as a beamline. The beam is transported from one viewscreen to the next one, corrected each time by a preceding orbit corrector. Simulations show that this procedure improves the root mean square value of the observed orbit deviations at the viewscreens, and reduces the value of the maximum beam excursions. Extending the number of monitors by 16 'q-monitors', thus enables the use of all 32 available orbit correctors and improves the root mean square value by another factor 3: the average reduction of x sub(root mean square) in this case becomes about a factor 10.
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A number of proposed applications of electromagnetic waves require that the radiation beam maintain a high intensity over an appreciable propagation distance. These applications include, among others, power beaming, advanced radar...
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A number of proposed applications of electromagnetic waves require that the radiation beam maintain a high intensity over an appreciable propagation distance. These applications include, among others, power beaming, advanced radar, laser acceleration of particles and directed-energy sources. The quest to achieve these objectives has led to a resurgence of research on diffraction theory. This report presents a survey and critique of the analyses and experimental tests of solutions of the wave equation in connection with so-called diffractionless and other directed radiation beams. The examples discussed in this paper include electromagnetic missiles, Bessel beams, electromagnetic directed energy pulse trains, and electromagnetic bullets. Electromagnetic wave propagation.
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This research considered the use of adaptive antennas in packet radio networks(PRNs). By using an adaptive array at a packet radio terminal, the receiving pattern of a terminal can change in response to each received packet. For e...
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This research considered the use of adaptive antennas in packet radio networks(PRNs). By using an adaptive array at a packet radio terminal, the receiving pattern of a terminal can change in response to each received packet. For example, in a slotted system, a terminal with an adaptive array can receive one or more packets correctly in a slot even when the slot contains colliding packets, because the array automatically nulls the colliding packets. Under this contract, we have first studied the performance of a single packet radio terminal using a multibeam adaptive array. The throughput-delay performance of the packet terminal has been evaluated for both slotted and unslotted channels. In addition, we have also studied the throughput-delay performance of a small slotted network that uses a single-beam adaptive array at each terminal.
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A Multifunction Impulse Radiating Antenna (IRA) is an extension of a standard IRAthat has the additional flexibility of an adjustable beam width. This a just ability is implemented by defocusing the feed to select between a narrow...
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A Multifunction Impulse Radiating Antenna (IRA) is an extension of a standard IRAthat has the additional flexibility of an adjustable beam width. This a just ability is implemented by defocusing the feed to select between a narrow or broad beam. We provide the theory of operation of the antenna, for both in focus and out of focus situations. Furthermore, we built and tested a design with a 46 cm diameter. We found reasonable agreement of the experiment with theory, although some work remains to be done in refining the feed point.
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