WE3 —  Wednesday Session 3   (13-Sep-23   13:30—14:40)
Chair: L. Bobb, DLS, Oxfordshire, United Kingdom
Paper Title Page
WE3I01 Gas Jet-Based Fluorescence Profile Monitor for Low Energy Electrons and High Energy Protons at LHC 312
  • O. Sedláček, A.R. Churchman, A. Rossi, G. Schneider, C.C. Sequeiro, K. Sidorowski, R. Veness
    CERN, Meyrin, Switzerland
  • M. Ady, S. Mazzoni, M. Sameed
    European Organization for Nuclear Research (CERN), Geneva, Switzerland
  • P. Forck, S. Udrea
    GSI, Darmstadt, Germany
  • O. Sedláček, O. Stringer, C.P. Welsch, H.D. Zhang
    The University of Liverpool, Liverpool, United Kingdom
  • O. Sedláček, O. Stringer, C.P. Welsch, H.D. Zhang
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  • A. Webber-Date
    Cockcroft Institute, University of Liverpool, Liverpool, United Kingdom
  The ever-developing accelerator capabilities of increasing beam intensity, e.g. for High Luminosity LHC (HL-LHC), demand novel non-invasive beam diagnostics. As a part of the HL-LHC project a Beam Gas Curtain monitor (BGC), a gas jet-based fluorescence transverse profile monitor, is being developed. The BGC uses a supersonic gas jet sheet that traverses the beam at 45° and visualizes a two-dimensional beam-induced fluorescent image. The principle of observing photons created by fluorescence makes the monitor insensitive to present electric or magnetic fields. Therefore, the monitor is well suited for high-intensity beams such as low-energy electron beam of Hollow Electron Lens (HEL), and HL-LHC proton beam, either as a profile or an overlap monitor. This talk will focus on the first gas jet measured transverse profile of the 7keV hollow electron beam. The measurements were carried out at the Electron Beam Test Stand at CERN testing up to 5A beam for HEL. A comparison with Optical Transition Radiation measurements shows consistency with the BGC results. The BGC installation of January 2023 at LHC is shown, including past results from distributed gas fluorescence tests.  
slides icon Slides WE3I01 [7.338 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-IBIC2023-WE3I01  
About • Received ※ 06 September 2023 — Revised ※ 08 September 2023 — Accepted ※ 27 September 2023 — Issue date ※ 02 October 2023
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
WE3C02 Development of a Precise 4d Emittance Meter Using Differential Slit Image Processing 318
  • B.K. Shin, G. Hahn
    PAL, Pohang, Republic of Korea
  • M. Chung, C.K. Sung
    UNIST, Ulsan, Republic of Korea
  We have developed a highly precise 4D emittance meter for X-Y coupled beams with 4D phase-space (x-x’, y-y’, x-y’, y-x’) which utilizes an L-shaped slit and employs novel analysis techniques. Our approach involves two types of slit-screen image processing to generate pepper-pot-like images with great accuracy. One which we call the "differential slit" method, was developed by our group. This approach involves combining two slit-screen images, one at position x and the other at position x + the size of the slit, to create a differential slit image. The other method we use is the "virtual pepper-pot (VPP)" method, which combines x-slit and y-slit images to produce a hole (x,y) image. By combining that hole images, we are able to take extra x-y’ and y-x’ phase-space. The "differential slit" method is crucial for accurately measuring emittance. Through simulations with 0.1 mm slit width using Geant4, the emittance uncertainties for a 5 nm rad and 0.2 mm size electron beam were 5% and 250% with and without the "differential slit", respectively. In this presentation, we provide a description of the methodology, the design of slit, and the results of the 4D emittance measurements.  
slides icon Slides WE3C02 [4.459 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-IBIC2023-WE3C02  
About • Received ※ 30 August 2023 — Revised ※ 13 September 2023 — Accepted ※ 26 September 2023 — Issue date ※ 28 September 2023
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
WE3C03 Radiation Hard Beam Profile Monitors for the North Experimental Beamlines CERN 321
  • E. Buchanan
    European Organization for Nuclear Research (CERN), Geneva, Switzerland
  • J. Cenede, S. Deschamps, W. Devauchelle, A. Frassier, J.N.G. Kearney, R.G. Larsen, I. Ortega Ruiz
    CERN, Meyrin, Switzerland
  A new radiation hard profile monitor is being researched and developed for the North Area Beamlines at CERN. The monitor must have a spatial resolution of 1 mm or less, an active area of 20 x 20 cm, a low material budget (~0.3%) and be operational in a beam that has a maximum rate of ~2x1011 p/s in the full energy range of 0.5 ¿ 450 GeV/c. The current focus is the study of different detection mediums: silica optical fibres (Cherenkov radiation), glass capillaries filled with liquid scintillator, and hollow core optical fibres filled with scintillation gasses. Prototypes of the different fibre candidates have been tested with an Ultra-High Dose Rate electron beam, a low intensity hadron beam and will be tested with a high intensity hadron beam during summer 2023. The key properties to compare between the different fibres are the light yield and radiation tolerance. In parallel, the performance of the fibres is being tested for their compatibility of use for FLASH medical therapy applications.  
slides icon Slides WE3C03 [4.294 MB]  
DOI • reference for this paper ※ doi:10.18429/JACoW-IBIC2023-WE3C03  
About • Received ※ 29 August 2023 — Revised ※ 08 September 2023 — Accepted ※ 12 September 2023 — Issue date ※ 18 September 2023
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)