| Paper |
Title |
Page |
| MOPLT111 |
On using NEA Cathodes in an RF Gun
|
797 |
| |
- M. Huening
Fermilab, Batavia, Illinois
|
|
| |
RF guns have been proven to deliver high brightness beams and therefore appear attractive as electron source for a linear collider. Only so far no polarized beams have been produced. To create a polarized electron beam GaAs NEA cathodes are used. Operating rf guns with a NEA cathode poses concerns in three areas, oxidation by residual gas, ion bombardment, and electron bombardment. In this paper we report about an attempt to reduce the vacuum pressure inside the gun by cooling it to cryogenic temperatures. Furthermore the energy deposition by ions and electrons will be quantified.
|
|
| MOPLT136 |
Reliability Simulations for a Linear Collider
|
857 |
| |
- N. Phinney, T.M. Himel, M.C. Ross
SLAC/NLC, Menlo Park, California
- P. Czarapata, H. Edwards, M. Huening
Fermilab, Batavia, Illinois
|
|
| |
A new flexible tool for evaluating accelerator reliability was developed as part of the US Linear Collider Technology Comparison Study. The linear collider designs considered were based on the GLC/NLC X-band and TESLA Superconducting proposals, but modified to meet the US physics requirements. To better model some of the complexities of actual operation, a simulation program was written, which included details such as partial fixes or workarounds, hot-swappable repairs, multiple simultaneous repairs, cooldown periods before access, staged recovery from an outage, and both opportunistic and scheduled machine development. The main linacs and damping rings were modeled in detail with component counts taken from the designs, and using MTBFs and MTTRs from existing accelerator experience. Other regions were assigned a nominal overall failure rate. Variants such as a single tunnel or conventional positron source were also evaluated, and estimates made of the sensitivity to recovery or repair times. While neither design was predicted to be sufficiently reliable given present experience, the required improvements were estimated to increase the overall project cost by only a few percent.
|
|
| TUPLT150 |
Vector Sum Control of an 8 GeV Superconducting Proton Linac
|
1482 |
| |
- M. Huening, G.W. Foster
Fermilab, Batavia, Illinois
|
|
| |
Fermilab is investigating the feasibility of an economical 8 GeV superconducting linac for H-. In order to reduce the construction costs it is considered to fan out the rf power to a string of accelerating structures per klystron. Below 1 GeV the individual fluctuations of the cavities will be compensated by high power phase shifters, above 1 GeV the longitudinal dynamics are sufficiently damped to consider omitting the phaseshifters. The impact of this setup on the field stability of individual cavities and ultimately the beam energy has been studied.
|
|
| THPLT133 |
Simulation of RF Control of a Superconducting Linac for Relativistic Particles
|
2771 |
| |
- M. Huening, P. Bauer, G.W. Foster
Fermilab, Batavia, Illinois
|
|
| |
We present a code to simulate the rf field and field control in a superconducting linac for relativistic heavy particles. In such a linac the field stability is strongly influenced by the longitudinal beam dynamics. So the code has to simulate both the field and the beam dynamics with the resulting varying beam loading. Other effects included in the simulation are Microphonics and Lorentz force. The code can simulate both single cavity and vector sum control.
|
|