Fabrication and Tolerance Issues and their Influence on Multi-Bunch BBU and Emittance Dilution in the Construction of X-Band RDDS Linacs for the NLC

نویسندگان

  • R. M. Jones
  • R. H. Miller
  • T. O. Raubenheimer
  • G. V. Stupakov
چکیده

The main linacs of the Next Linear Collider (NLC) will contain several thousand X-band RDDS (Rounded Damped Detuned Structures). The transverse wakefield in the structures is reduced by detuning the modal frequencies such that they destructively interfere and by four damping manifolds per structure which provide weak damping. Errors in the fabrication of the individual cells and in the alignment of the cells will reduce the cancellation of the modes. Here, we calculate the tolerances on random errors in the synchronous frequencies of the cells and the cell-to-cell alignment.

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Emittance Dilution and Beam Break up in the Jlc/nlc

The passage of a multi-bunch beam through an X-band accelerator with cells and structures misaligned gives rise to wakefields which disrupt succeeding bunches. As a consequence, there is growth in the overall emittance of the final colliding bunches. Here we study this process in the context of a JLC-NLC which employs the recently developed RDDS (Rounded Damped Detuned Structures) accelerators ...

متن کامل

Emittance Dilution Simulations for Normal Conducting and Superconducting Linear Colliders

Abstract An electron (or positron) multi-bunch train traversing several thousand accelerator structures can be distorted by the long-range wakefields left behind accelerated bunches. These wakefields can at the very least, give rise to a dilution in the emittance of the beam and, at worst can lead to a beam break up instability. We investigate the emittance dilution that occurs for various freq...

متن کامل

Dipole Mode Detuning in the Nlc Injector Linacs

A major consideration in the design of the accelerator structures in the injector linacs of the JLC/NLC[1] is to keep the wakefield effects within tolerances for both the nominal (2.8 ns) and alternate (1.4 ns) bunch spacings. One important multi-bunch wakefield effect is beam break-up (BBU), where a jitter in injection conditions of a bunch train is amplified in the linac; another is static em...

متن کامل

A Study of Coupler-trapped Modes in X-band Linacs for the Glc/nlc

Each of the X-band accelerating structures for the GLC/NLC (Global Linear Collider/Next Linear Collider) consists of 55 cells which accelerate a train of charged bunches. The cells are carefully designed to ensure that the transverse wakefield left behind each bunch does not disrupt the trailing bunches, but some modes are trapped in the region of the coupler cells. These modes can give rise to...

متن کامل

A Compact X-band Linac for an X-ray Fel*

With the growing demand for FEL light sources, cost issues are being reevaluated. To make the machines more compact, higher frequency room temperature linacs are being considered, specifically ones using C-band (5.7 GHz) rf technology, for which 40 MV/m gradients are achievable. In this paper, we show that an X-band (11.4 GHz) linac using the technology developed for NLC/GLC can provide an even...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2000