Conveners
Normal conducting RF: 1
- Tetsuo Abe
Normal conducting RF: 2
- Ankur Dhar (SLAC National Accelerator Lab)
Normal conducting RF: 3
- Emilio Nanni (SLAC National Accelerator Laboratory)
Normal conducting RF: 3
- Evgenya Simakov (LANL)
Presentation materials
The first Southern Hemisphere X-band Laboratory for Accelerators and Beams (X-LAB) has been commissioned at the University of Melbourne. One of the key projects within this laboratory involves repurposing half of the CERN X-band test stand XBOX3, now known as Mel-BOX.
This initiative aims to validate the performance of high-gradient travelling wave accelerating structures, crucial for the...
Over recent years, significant efforts have been dedicated to validating the reliability and functionality of X-band technology at extremely high peak fields and accelerating gradients to achieve the realization of increasingly compact linacs. The Eupraxia@SPARC_LAB project entails the development of 1GeV Linac utilizing a X-band booster comprising 16 accelerating structures operating at a...
This presentation details the design and fabrication process of a prototype of a normal-conducting X-band accelerator structure, which we denominate Smartcell. These structures, achieved through brazing/bonding techniques, are crucial components for future linear colliders.
We will cover the brazing/bonding geometry, materials selection and their implications, variations in heat cycles, and...
A dielectric assist accelerating (DAA) structure, which consists special dielectric cell structures operating in the TM02n mode, is greatly superior in power efficiency compared with the conventional normal conducting copper structures. On the other hand, DAA structures stays at a low achievable accelerating gradient due to multipactor and breakdowns. To overcome these problems, we try to...
The initial design of the capture cavities for the continuous wave (CW) polarized positron beams at Jefferson Lab (Ce+BAF) is presented. A chain of standing wave multi-cell copper cavities inside a solenoid tunnel are selected to bunch/capture positrons. The cavity design strategy is presented to accommodate constrains from the large phase distribution of the incident beams, RF power,...
To achieve target performance of the C3 accelerator, many elements will need to be manufactured, assembled, and aligned in use to very tight tolerances. Testing of accelerating structure manufacturing, alignment, mounting, and liquid nitrogen cooling will be performed at SLAC using an accelerator length of approximately 2 meters. This talk will review progress and plans toward commissioning a...
In this paper we report on the design, fabrication, tuning and high-power RF testing of the fundamental accelerating structure for the Cool Copper Collider (CCC). The results presented here cover the temperature range from room temperature to liquid nitrogen boil off: 20oC - 77 K
At room temperature, RT, with a N2 gas purge of 1 atmosphere, the CCC structure was tuned to a resonance...
We will present results from high gradient structure testing of C-band single-cell copper (Cu) and copper silver (CuAg) accelerating structures at 77 K. C-band accelerators have been of particular interest in recent years due to their ability to provide high gradients and transport high charge beams for applications ranging from colliders to medical technologies. These technologies are made...
Standing wave structures typically operate at the pi-mode. Evidently the cell length of such a structure is half a wavelength. However, maximal shunt impedance per unit length was found to be at a cell length of 3/8 wavelength, which corresponds to phase advance per cell of 135 degrees. A distributed coupling structure at 5.712 GHz was developed based on the high efficient 135/degree phase...
The initial proposed design of the Cold Copper Collider (C3) is based on a distributed coupling accelerating (DCA) rf structure where the phase advance between the accelerating standing wave cavities is π. In these cavities the aperture radius is 2.624 mm and the corresponding shunt impedance is 300 MΩ/m with 77K copper walls. We propose a novel DCA rf structure with 3π/4 phase advance between...
This talk will report on the status of commissioning of the Cathodes And Radio-frequency Interactions in Extremes (CARIE) high gradient C-band RF photoinjector test stand at Los Alamos National Laboratory. We are assembling and testing the high gradient photoinjector capable of producing electric fields at the cathodes up to 250 MV/m. The photoinjector will be powered by a 50 MW, 5.712 GHz...
The Low-Level RF (LLRF) control circuits of linear accelerators (LINACs) are conventionally realized with heterodyne based architectures, which have analog RF mixers for up and down conversion with discrete data converters. We have developed a new LLRF platform for C band linear accelerator based on the Frequency System-on-Chip (RFSoC) device from AMD Xilinx. The integrated data converters in...
Future colliders will require injector linacs to accelerate large electron bunches over a wide range of energies. For example the Electron Ion Collider requires a pre-injector linac from 4 MeV up to 400 MeV over 35 m. Currently this linac is being designed with 3 m long traveling wave structures, which provide a gradient of 16 MV/m. We propose the use of a 1 m distributed coupling design as a...
High-energy particle accelerators are crucial to the next big discovery in particle physics. To reduce the size and cost of particle accelerators, increasing the accelerating gradient (energy gain per unit length for the particle beam) is of critical importance. Advanced accelerator concepts (AACs) hold the promise of revolutionary future particle colliders with dramatically higher gradients...
The acceleration gradient is a critical parameter affecting the feasibility and cost of large-scale particle accelerators such as normal conducting linear colliders. The main obstacle to increasing the acceleration gradient or improving the reliability of a linear accelerator at a certain gradient is vacuum RF breakdown. To understand the basic physics of the RF breakdown in cavities suitable...
Side-coupled structures operated with π/2 mode have been widely used particularly for compact linacs. The structure has various advantages; however, there are some difficulties in fabrication due to many complicated parts to be bonded in the conventional fabrication method. On the other hand, longitudinally-split structures are easy to fabricate due to the small number of parts (two halves or...
