High frequency planar accelerating structures for future linear colliders

Conference · Sat Dec 31 04:00:00 EST 1994

OSTI ID:314124

Yu, D; Ben-Menahem, S ^[1]; Wilson, P; Miller, R; Ruth, R ^[2]; Nassiri, A ^[3]

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1. DULY Research Inc., Rancho Palos Verdes, CA (United States)
2. Stanford Univ., CA (United States). Stanford Linear Accelerator Center
3. Argonne National Lab., IL (United States)

Modern microfabrication techniques based on deep etch x-ray lithography, e.g., LIGA, can be used to produce large-aspect-ratio, metallic or dielectric, planar structures suitable for high-frequency RF acceleration of charged particle beams. Specifically, these techniques offer significant advantages over conventional manufacturing methods for future linear colliders (beyond NLC, the Next Linear Collider) because of several unique systems requirements. First, to have the required ac wall plug power within reasonable limits, such future linear colliders (5 TeV) must operate at high frequency (30 GHz). Secondly, luminosity requirements suggest the use of multi-bunch acceleration of electrons and positrons in the linear collider. Thirdly, in order to clearly discriminate physics events in the final interaction point at which electrons and positrons collide, it is required that secondary particle production from beamstrahlung be minimized. Flat electron and positron beams with a large aspect ratio will be beneficial in reducing beamstrahlung in the final focus region, but cause the beam to be more sensitive to wakefields in the vertical dimension. In principle, a flat beam can be accelerated in a planar structure with reduced wakefield in the vertical direction for the entire length of the accelerator. The LIGA process is particularly suitable for manufacturing miniaturized, planar, asymmetric cavities at high frequency. The main advantages of the LIGA process are fabrication of structures with high aspect ratio, small dimensional tolerances, and arbitrary mask shape (cross-section). Other advantages include mass-production with excellent repeatability and precision of up to an entire section of an accelerating structure consisting of a number of cells. It eliminates the need of tedious machining and brazing, for example, of individual disks and cups in conventional disk-loaded structures. Also, planar input/output couplers for the accelerating structure can be easily machined in the same process with the cavities. The new fabrication technique should substantially reduce the manufacturing cost of such accelerating structures.

• Research Organization: DULY Research Inc., Rancho Palos Verdes, CA (United States)
• Sponsoring Organization: USDOE Office of Energy Research, Washington, DC (United States)
• DOE Contract Number: FG03-94ER86007
• OSTI ID: 314124
• Report Number(s): CONF-940681--; ON: DE99001741
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
BEAM LUMINOSITY
CAVITY RESONATORS
DESIGN
ELECTROMAGNETIC RADIATION
LINEAR COLLIDERS
MANUFACTURING
MINIATURIZATION
RF SYSTEMS