Author: Ushakov, A.
Paper Title Page
MOPOTK012 Concept of a Polarized Positron Source for CEBAF 457
SUSPMF058   use link to see paper's listing under its alternate paper code  
 
  • S.H. Habet, R.M. Bodenstein, S.A. Bogacz, J.M. Grames, A.S. Hofler, R. Kazimi, F. Lin, M. Poelker, Y. Roblin, A. Seryi, R. Suleiman, A.V. Sy, D.L. Turner
    JLab, Newport News, Virginia, USA
  • A. Ushakov
    Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France
  • C.A. Valerio-Lizárraga
    ECFM-UAS, Culiacan, Sinaloa, Mexico
  • E.J-M. Voutier
    LPSC, Grenoble Cedex, France
 
  Funding: Laboratoire de Physique des 2 Infinis Irène Joliot-Curie Université Paris-Saclay -> Eric Voutier : eric.voutier@ijclab.in2p3.fr.
Positron beams would provide new and meaningful probes for the experimental program at the Thomas Jefferson National Accelerator Facility (JLab), including but not limited to future hadronic physics and dark matter experiments. Critical requirements involve generating positron beams with a high degree of spin polarization, sufficient intensity and a continuous-wave (CW) bunch train compatible with acceleration to 12 GeV at the Continuous Electron Beam Accelerator Facility (CEBAF). To address these requirements, a polarized positron injector based upon the bremsstrahlung of an intense CW spin polarized electron beam is considered*. First a polarized electron beam line provides >1 mA of polarized electrons at ~120 MeV to a high-power target for positron production. Next, a second beam line collects, shapes and aligns the spin of positrons for users. Finally, the positron beam is matched into the CEBAF acceptance for acceleration and transport to the end stations with energies up to 12 GeV. An optimized layout to provide positrons beams with intensity >100 nA (polarized) or intensity >3 µA (unpolarized) will be discussed in this poster.
* D. Abbott et al., "Production of Highly Polarized Positrons Using Polarized Electrons at MeV Energies", Phys. Rev. Lett., 116, 214801 (2016)
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK012  
About • Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 06 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOPT054 Target Studies for the FCC-ee Positron Source 1979
 
  • F. Alharthi, I. Chaikovska, R. Chehab, S. Ogur, A. Ushakov, S. Wallon
    Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France
  • L. Bandiera, A. Mazzolari, M. Romagnoni, A.I. Sytov
    INFN-Ferrara, Ferrara, Italy
  • J. Diefenbach, W. Lauth
    IKP, Mainz, Germany
  • O. Khomyshyn
    Taras Shevchenko National University of Kyiv, Kyiv, Ukraine
  • D.M. Klekots
    National Taras Shevchenko University of Kyiv, The Faculty of Physics, Kyiv, Ukraine
  • V.V. Mytrochenko
    NSC/KIPT, Kharkov, Ukraine
  • P. Sievers, Y. Zhao
    CERN, Meyrin, Switzerland
  • M. Soldani
    Università degli Studi di Ferrara, Ferrara, Italy
 
  FCC-ee injector study foresees 3.5~nC electron and positron bunches with 200 Hz repetition and 2 bunches per linac pulse at 6~GeV extraction energy. Regarding the possible options of positron production, we retain both of the conventional amorphous target and the hybrid target options. The hybrid scheme uses an intense photon production by 6 GeV electrons impinging on a crystal oriented along a lattice axis. In such a way, it involves two targets: a crystal as a photon radiator and an amorphous target-converter. Therefore, to avoid early failure or damage of the target, the candidate materials for the crystal and conversion targets have started to be tested by using the intense electron beam at Mainzer Mikrotron in Germany by the end of 2021. By manipulating the beam intensity, focusing, and chopping, a Peak Energy Deposition Density in the tested targets could be achieved close to that generated by the electron/photon beam in the FCC-ee positron target. Radiation-damage studies of the crystal sample have been also performed allowing estimating the effect on the photon enhancement used in the hybrid positron source.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT054  
About • Received ※ 16 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 21 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)