Beam Dynamics Activities and Plans at LBL

Technical Report · Fri Jul 01 00:00:00 EDT 1988

DOI:https://doi.org/10.2172/1000486· OSTI ID:1000486

Chattopadhyay, S

On-going beam dynamics studies at LBL are performed in connection with the 1-2 GeV Advanced Light Source (ALS), the SSC, Collider Physics (Novel Power Sources) and Heavy Ion Fusion Accelerator Research (HIFAR). Exploratory activities include generic research on (a) high-brightness, low-emittance storage rings and linacs for the TeV-scale future linear colliders, b{bar b} facilities, etc., (b) beam dynamics and optics of incoherent and coherent undulator radiation, (c) Free Electron Laser Studies, (d) development of a high-brightness laser-driven RF photocathode electron source for the LBL-LLNL-SLAC collaboration on Relativistic Klystrons and (e) new methods of acceleration. The major physics issues being studied in connection with the ALS are the effects of undulators and wigglers on storage ring beam dynamics (nonlinear stability and stable dynamic aperture), short bunch-length collective phenomena and multi-loop high-fidelity orbit and photon beam feedback for stability of the radiation source. In connection with the first issue, detailed nonlinear behavior of the electron beam in presence of insertion devices in an otherwise symmetric low-emittance lattice are being pursued and various compensation schemes are being investigated. We held a workshop on this specialized topic May 17-20, 1988 at LBL, where participants from international laboratories such as Sincrotrone Trieste, KEK, SLAC, BNL, ANL, etc., participated. Contributions will soon be published as proceedings to this workshop. Considerable insight into the physics of short bunches has been gained through a similar workshop last year on the 'Impedance Beyond Cutoff' at LBL, where a realistic picture of the impedance spectrum at high frequencies corresponding to short bunch lengths emerged. The focus at the moment is on the nature of coherent instabilities potentially driven by this high-frequency impedance. Securing a stable photon beam against vibrations and other noise sources simultaneously at several beam lines in a synchrotron radiation source is nontrivial and requires multi-loop orbit feedback system with accompanying cross-talk. A possible control algorithm is under investigation. In other matters, experimental study of dynamic effects with undulators is being planned at BESSY and other laboratories; impedance measurement test facility; instrumentation and feedback, advanced accelerator control systems and optics of synchrotron radiation are being pursued actively. Possibilities of infra-red and XUV FEL's as upgrades to the ALS are also being considered. Collaboration with LLNL and SLAC for the Relativistic Klystron is an ongoing activity. This promising power-source is being actively investigated both theoretically and experimentally with a goal towards a 1 GeV test experiment in late 1989. In this connection, studies of a conceptual design of a bright injector for the test experiment has been undertaken at Berkeley. The Conceptual Design Report will be completed in October, 1988. The design utilizes a high-brightness laser-driven RF photocathode electron gun, similar to the LANL early experiments, together with achromatic magnetic bunching and transport systems and diagnostics. The design is performed with attention to possible use in an FEL as well. Heteroenergetic collision optics for a possible b{bar b} facility based on 12 GeV PEP and a 2 GeV high-brightness ring has been obtained. The possible implications of collective effects is under study presently.

• Research Organization: Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
• Sponsoring Organization: Accelerator& Fusion Research Division
• DOE Contract Number: DE-AC02-05CH11231
• OSTI ID: 1000486
• Report Number(s): LBL-25667; TRN: US201101%%633
• Country of Publication: United States
• Language: English

Related Subjects

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ADVANCED LIGHT SOURCE
BEAM DYNAMICS
CONTROL SYSTEMS
ELECTRON BEAMS
ELECTRON GUNS
ELECTRON SOURCES
FREE ELECTRON LASERS
HEAVY IONS
IMPEDANCE
LINEAR ACCELERATORS
LINEAR COLLIDERS
OPTICS
PHOTON BEAMS
PHYSICS
RADIATION SOURCES
SAFETY REPORTS
STORAGE RINGS
SUPERCONDUCTING SUPER COLLIDER
SYNCHROTRON RADIATION
SYNCHROTRON RADIATION SOURCES
WIGGLER MAGNETS