Author: Knight, E.W.
Paper Title Page
MOZE3 Emittance Measurements and Simulations from an X-Band Short-Pulse Ultra-High Gradient Photoinjector 45
  • G. Chen, D.S. Doran, C.-J. Jing, S.Y. Kim, W. Liu, W. Liu, P. Piot, J.G. Power, C. Whiteford, E.E. Wisniewski
    ANL, Lemont, Illinois, USA
  • C.-J. Jing, E.W. Knight, S.V. Kuzikov
    Euclid TechLabs, Solon, Ohio, USA
  • C.-J. Jing
    Euclid Beamlabs, Bolingbrook, USA
  • X. Lu, P. Piot, W.H. Tan
    Northern Illinois University, DeKalb, Illinois, USA
  Funding: This work is supported by the U.S. DOE, under award No. DE-SC0018656 to NIU, DOE SBIR grant No. DE-SC0018709 to Euclid Techlabs LLC, and contract No. DE-AC02-06CH11357 with ANL.
A program is under way at the Argonne Wakefield Accelerator facility, in collaboration with the Euclid Techlabs and Northern Illinois University (NIU), to develop a GeV/m scale photocathode gun, with the ultimate goal of demonstrating a high-brightness photoinjector beamline. The novel X-band photoemission gun (Xgun) is powered by high-power, short RF pulses, 9-ns (FWHM), which, in turn, are generated by the AWA drive beam. In a previous proof-of-principle experiment, an unprecedented 400~MV/m gradient on the photocathode surface* was demonstrated. In the current version of the experiment, we added a linac to the beamline to increase the total energy and gain experience tuning the beamline. In this paper, we report on the very first result of emittance measurement as well as several other beam parameters. This preliminary investigation has identified several factors to be improved on in order to achieve one of the ultimate goals; low emittance.
* W. H. Tan et al., "Demonstration of sub-GV/m Accelerating Field in a Photoemission Electron Gun Powered by Nanosecond X-Band Radiofrequency Pulses", 2022. arXiv:2203.11598v1
slides icon Slides MOZE3 [5.565 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-MOZE3  
About • Received ※ 03 August 2022 — Revised ※ 05 August 2022 — Accepted ※ 11 August 2022 — Issue date ※ 14 August 2022
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THYE4 Development of an Ultra-Low Vibration Cryostat Based on a Closed-Cycle Cryocooler 874
  • R.W. Roca
    Illinois Institute of Technology, Chicago, Illinois, USA
  • E.W. Knight, R.A. Kostin, Y. Zhao
    Euclid TechLabs, Solon, Ohio, USA
  Low temperature and low vibration cryostats are useful in a variety of applications such as x-ray diffraction, quantum computing, x-ray monochromators and cryo-TEMs. In this project, we explore an ultra-low vibration cryostat with the cooling provided by a closed cycle cryocooler. Closed-cycle cryocoolers inevitably introduce vibrations into the system, and in this project, flexible copper braiding was used to decouple vibrations and provide cooling at the same time. In order to develop the cryostat, capacity map of a two stage Sumitomo cryocooler was measured as well as vibration transmission through different copper braids using an IR interferometer. This paper covers the capacity map and vibration measurements in the first prototype.  
slides icon Slides THYE4 [4.989 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-THYE4  
About • Received ※ 16 July 2022 — Revised ※ 10 August 2022 — Accepted ※ 20 August 2022 — Issue date ※ 12 September 2022
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THZE3 An Electrodeless Diamond Beam Monitor 904
  • S.V. Kuzikov, P.V. Avrakhov, C.-J. Jing, E.W. Knight
    Euclid TechLabs, Solon, Ohio, USA
  • D.S. Doran, C.-J. Jing, J.G. Power, E.E. Wisniewski
    ANL, Lemont, Illinois, USA
  • C.-J. Jing
    Euclid Beamlabs, Bolingbrook, USA
  Funding: The work was supported by DoE SBIR grant #DE-SC0019642.
Being a wide-band semiconductor, diamond can be used to measure the flux of passing particles based on a particle-induced conductivity effect. We recently demonstrated a diamond electrodeless electron beam halo monitor. That monitor was based on a thin piece of diamond (blade) placed in an open high-quality microwave resonator. The blade partially intercepted the beam. By measuring the change in RF properties of the resonator, one could infer the beam parameters. At Argonne Wakefield Accelerator we have tested 1D and 2D monitors. To enhance the sensitivity of our diamond sensor, we proposed applying a bias voltage to the diamond which can sustain the avalanche of free carriers. In experiment carried out with 120 kV, ~1 µA beam we showed that the response signal for the avalanche monitor biased with up to 5 kV voltage can be up to 100 times larger in comparison with the signal of the same non-biased device.
slides icon Slides THZE3 [4.257 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-THZE3  
About • Received ※ 20 July 2022 — Revised ※ 28 July 2022 — Accepted ※ 06 August 2022 — Issue date ※ 08 August 2022
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