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Development of a 100 MeV CW proton LINAC has been planned at CAT. This LINAC will be needing CW rf power in the frequency
ranges of 350 MHz and 700 MHz for its RFQ and DTL/CCDTL/SFDTL structures respectively. The power to the accelerating structures
will be produced by either 1 MW CW or 250 kW CW klystrons/inductive output tubes (HOM IOTs). The power needed by respective
feed points in the structure is max. 250 kW which will be powered by splitting the power from 1 MW klystron/klystrode into
four channels by using a wave-guide system. In case of using 250 kW tubes the power to the structures will be provided directly
from each tube. Two types of wave-guide transmission system have been considered, viz, WR 2300 for 350 MHz rf needs and WR
1500 for 700 MHz rf needs. The typical wave-guide system has been designed using the 1 MW CW klystron followed by wave-guide
filter, dual directional coupler, high-power circulator, three 3 dB magic TEE power dividers to split the main channel into
four equal channels of 250 kW each. Each individual channel has dual directional couplers, flexible wave-guide sections and
high power ceramic vacuum window. The circulator and each power divider is terminated into the isolated ports by high power
CW loads. Out of the four channels three channels have phase shifters. Present paper describes the technological aspects and
design specifications-considerations for these stringent requirements. 相似文献
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Dr. Roberta Pievo Brigitta Angerstein Dr. Alistair J. Fielding Dr. Christian Koch Prof. Dr. Ivo Feussner Prof. Dr. Marina Bennati 《Chemphyschem》2013,14(18):4094-4101
Electron paramagnetic resonance (EPR) spectroscopy in combination with the rapid freeze‐quench (RFQ) technique is a well‐established method to trap and characterize intermediates in chemical or enzymatic reactions at the millisecond or even shorter time scales. The method is particularly powerful for mechanistic studies of enzymatic reactions when combined with high‐frequency EPR (ν≥90 GHz), which permits the identification of substrate or protein radical intermediates by their electronic g values. In this work, we describe a new custom‐designed micro‐mix rapid freeze‐quench apparatus, for which reagent volumes for biological samples as small as 20 μL are required. The apparatus was implemented with homemade sample collectors appropriate for 9, 34, and 94 GHz EPR capillaries (4, 2, and 0.87 mm outer diameter, respectively) and the performance was evaluated. We demonstrate the application potential of the RFQ apparatus by following the enzymatic reaction of PpoA, a fungal dioxygenase producing hydro(pero)xylated fatty acids. The larger spectral resolution at 94 GHz allows the discernment of structural changes in the EPR spectra, which are not detectable in the same samples at the standard 9 GHz frequency. 相似文献
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中国散裂中子源RFQ的热分析 总被引:1,自引:0,他引:1
射频四级场(RFQ)加速器的水冷具有以下两种功用: 首先它可以把射频场发热带走, 维持RFQ腔的热稳定性及限制RFQ强体形变幅度; 其次, 当RFQ失谐时, 它还可以用来进行RFQ的调谐, 而同时又基本不影响RFQ的射频场分布. 由于RFQ粒子的传输效率对射频场的分布极其敏感, 在RFQ的运行中不再采用传统的用调谐器对RFQ进行调谐的方法. 本文通过热分析, 确定了RFQ加速器的水冷管道的数量和布局及最佳工作水温; 确定了RFQ失谐时, 如何利用水温变化来对RFQ进行调谐的方法. 相似文献
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It is proposed to construct a spallation neutron source (SNS) at Centre for Advanced Technology (CAT) based on a 1 GeV proton
synchrotron with 100 MeV H− LINAC as injector. Additionally, the LINAC can form the first 100 MeV part of a 1 GeV proton LINAC to be built in future
for accelerator driven system (ADS) applications. We are exploring a configuration of the 100 MeV LINAC which will consist
of an H− ion source, a 4–6 MeV RFQ followed either by a 20 MeV drift tube LINAC (DTL) and 100 MeV separated function drift tube LINAC
(SDTL) or a coupled cavity drift tube LINAC (CCDTL) structure. In this paper, we present the results of our preliminary physics
design studies of the RFQ-SDTL, RFQ-CCDTL and RFQ-DTL-SDTL configurations. The design of the 4.5 MeV RFQ is discussed along
with the matching sections between the RFQ-SDTL/DTL and RFQ-CCDTL. The choice of the accelerator configuration and that of
various parameters of the individual accelerator structures under consideration are discussed. The design objectives are to
arrive at a configuration which eases heat removal for CW operation and which is less prone to halo formation in order to
reduce the beam loss at higher energies. 相似文献
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P N Ostroumov 《Pramana》2002,59(6):895-913
The Nuclear Science Community in the Unites States has unanimously concluded that developments in both nuclear science and
its supporting technologies make building a world-leading Rare-Isotope Accelerator (RIA) facility for production of radioactive
beams the top priority. The RIA development effort involves several US Laboratories (ANL, JLAB, LBNL, MSU, ORNL). The RIA
facility includes a CW 1.4 GeV driver LINAC and a 100 MV post-accelerator both based on superconducting (SC) cavities operating
at frequencies from 48 MHz to 805 MHz. An initial acceleration in both LINACs is provided by room temperature RFQs. The driver
LINAC is designed for acceleration of any ion species; from protons up to 900 MeV to uranium up to 400 MeV/u. The novel feature
of the driver LINAC is an acceleration of multiple charge-state heavy-ion beams in order to achieve 400 kW beam power. Basic
design concepts of the driver LINAC are given. Several new conceptual solutions in beam dynamics, room temperature and SC
accelerating structures for heavy ion accelerator applications are discussed. 相似文献
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基于CST 微波工程软件对四杆型RFQ 的模拟运算,分析了在不同情况下不同的RFQ 结构参数σ/R与电极最大表面电场Emax 之间的关系,发现对应于不同RFQ 孔径下的最小的Emax,其结构参数σ/R 的值是不同的。同时发现改变σ/R,RFQ极间电场线性度始终保持在99.5% 以上,但σ/R 变大会微幅提升极间电场线性度。Based on the simulation on 4-rods RFQ by the CST MWS software, we analyzed the relationship between the RFQ’s structure parameter σ/R and the maximum electrode field Emax, and found that as the aperture R varies,the value of σ/R corresponding to the minimum Emax does not necessarily keep constant. We also found that the RFQ interelectrode field linearity maintains over 99.5% as σ/R veries, although it slightly increases as σ/R increases. 相似文献