Paper | Title | Page |
---|---|---|
TUPO054 | Fundamental Studies of Impurity Doping in 1.3 GHz and Higher Frequency SRF Cavities | 458 |
SPWR018 | use link to see paper's listing under its alternate paper code | |
TUOP01 | use link to see paper's listing under its alternate paper code | |
|
||
As the demand for more powerful, more efficient, and smaller superconducting RF accelerators continues to increase, both impurity doping and high-frequency cavities (> 1.3 GHz) have become hot topics for fundamental research because of their potential to significantly decrease surface losses and cost respectively. In this report, we present recent experimental and theoretical results on undoped and nitrogen-doped high-frequency cavities and on alternative doping agents in traditional 1.3 GHz cavities, with a focus on understanding the fundamental science of impurity doping. | ||
![]() |
Slides TUPO054 [1.956 MB] | |
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-TUPO054 | |
About • | paper received ※ 16 September 2018 paper accepted ※ 19 September 2018 issue date ※ 18 January 2019 | |
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
TUPO055 | Next Generation Nb3Sn SRF Cavities for Linear Accelerators | 462 |
|
||
Niobium-3 Tin (Nb3Sn) is a very promising alternative material for SRF accelerator cavities. The material can achieve higher quality factors, higher temperature operation and potentially higher accelerating gradients (~ 96 MV/m) compared to conventional niobium. This material is formed by vaporizing Sn in a high temperature vacuum furnace and letting the Sn absorb into a Nb substrate to form a 2-3 um Nb3Sn layer. Current Nb3Sn cavities produced at Cornell achieve Q ~ 1010 at 4.2 K and 17 MV/m. Here we present a summary of the current performance of Nb3Sn cavities at Cornell and recent progress in improving the accelerating gradient. | ||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-TUPO055 | |
About • | paper received ※ 20 September 2018 paper accepted ※ 21 September 2018 issue date ※ 18 January 2019 | |
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
TUPO057 | Low-temperature Baking and Infusion Studies for High-gradient ILC SRF Cavities | 466 |
|
||
Low-temperature infusion has become a hot-topic in SRF researches recently. Past results show that low-temperature infusion can produce high quality factor at medium accelerating fields. Also, 75°C baking recently has been shown to improve accelerating gradients of SRF cavities. Hence these treatments are very promising for reducing cost of the ILC. In this work, we present latest results of low temperature infusion and baking, showing that these treatments can improve SRF cavities performance. | ||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-TUPO057 | |
About • | paper received ※ 19 September 2018 paper accepted ※ 20 September 2018 issue date ※ 18 January 2019 | |
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
TUPO058 | Cool Down Studies for the LCLS-II Project | 470 |
|
||
The quality factor of the nitrogen-doped SRF cavities for the LCLS-II project are strongly impacted by cool down speed. A sufficiently fast cool down speed can produce large thermal gradient across a cavity and sufficiently expel magnetic flux when the cavity wall passes from the normal-conducting to the superconducting state. However, instrumentation in LCLS-II production cryomodules has been kept at a minimum, and additional information during the cool down of the modules is therefore desirable. In this work, we study if and how RF data can be used during cavity cool-down to determine the transition speeds of the individual cavities in the LCLS-II linac. | ||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-TUPO058 | |
About • | paper received ※ 19 September 2018 paper accepted ※ 20 September 2018 issue date ※ 18 January 2019 | |
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
TUPO059 | Latest Results of Salt Based Bipolar Electro-polishing R&D at Cornell | 473 |
|
||
Acid free electropolishing would be safer to use and friendlier to the environment. A collaboration, sup-ported by the DOE SBIR Phase-II program, between Faraday Technology Inc. and Cornell University focused on salt-based bipolar electropolishing (BEP). In this paper, we present the latest salt-based BEP results. The superconducting performance of a single-cell 1.3GHz cavity has been carefully analyzed, showing that salt-based BEP is promising, but still has large room for improvement. | ||
DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-TUPO059 | |
About • | paper received ※ 19 September 2018 paper accepted ※ 21 September 2018 issue date ※ 18 January 2019 | |
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
WE1A02 |
CBETA, a 4-turn ERL Based on SRF Linacs and Permanent Magnet Beam Transport | |
|
||
A collaboration between Cornell University and Brookhaven National Laboratory has designed a novel accelerator and is constructing it at Cornell: CBETA, the Cornell-BNL ERL Test Accelerator. The ERL technology that has been prototyped at Cornell for many years is being used, including a DC electron source and an SRF injector Linac with world-record current and normalized brightness in a bunch train, a high-current linac cryomodule optimized for ERLs, a high-power beam stop, and several diagnostics tools for high-current and high-brightness beams. BNL has designed a multi-turn ERL and a recirculating linac for eRHIC; in both designs the beam is transported many times around the 4 km long RHIC tunnel. The number of transport lines is minimized by using two arcs with Fixed Field Alternating Gradient design. This technique will be tested in CBETA, which has a single return for the 4-beam energies with strongly-focusing permanent magnets of Halbach type. The high-brightness beam with 150 MeV and up to 40 mA will have applications for Electron Ion Colliders (EICs), e.g. for their electron cooling, and for applications in industry, in nuclear physics, and in X-ray science. | ||
![]() |
Slides WE1A02 [6.367 MB] | |
Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |