WEA2WA —  WG-A   (20-Jun-18   11:00—12:30)
Chair: G. Franchetti, GSI, Darmstadt, Germany
Paper Title Page
WEA2WA01 High Intensity Effects of Fixed Target Beams in the CERN Injector Complex -1
  • E. Koukovini-Platia, H. Bartosik, M. Migliorati, G. Rumolo
    CERN, Geneva, Switzerland
  • M. Migliorati
    INFN-Roma1, Rome, Italy
  • M. Migliorati
    Sapienza University of Rome, Rome, Italy
  The current fixed target (FT) experiments at CERN are a complementary approach to the Large Hadron Collider (LHC) and play a crucial role in the investigation of fundamental questions in particle physics. Within the scope of the LHC Injectors Upgrade (LIU), aiming to improve the LHC beam production, the injector complex will be significantly upgraded during the second Long Shutdown (LS2). All non-LHC beams are expected to benefit from these upgrades. In this paper, we focus on the studies of the transverse instability in the Proton Synchrotron (PS), currently limiting the intensity of Time-Of-Flight (ToF) type beams, as well as the prediction of the impact of envisaged hardware modifications. A first discussion on the effect of space charge on the observed instability is also being presented.  
slides icon Slides WEA2WA01 [2.483 MB]  
WEA2WA02 Microbunched Electron Cooling (MBEC) for Future Electron-ion Colliders -1
  • G. Stupakov
    SLAC, Menlo Park, California, USA
  Funding: Work supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-76SF00515.
The Microbunched Electron Cooling (MBEC) is a promising cooling technique that can find applications in future hadron and electron-ion colliders. In this paper we give a qualitative derivation of the cooling rate for MBEC and estimate the cooling time for the eRHIC electron-ion collider. We then argue that MBEC with two plasma amplification stages should be sufficient to overcome the emittance growth due to the intra-beam scattering in eRHIC.
slides icon Slides WEA2WA02 [2.701 MB]  
High Intensity Studies with Paul Trap  
  • S.L. Sheehy
    STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
  Funding: Royal Society
To date our understanding of fundamental intensity limitations and studies of instabilities and resonances has been based on time-consuming accelerator-based experiments or on simulations, limited by computational power and noise artifacts that can obscure real beam physics effects. As beam intensities increase and new concepts emerge for high intensity machines, accelerator physicists require new methods, tools and modeling techniques to understand the complex dynamics of the intense beams involved. In this talk I will introduce a scaled experimental system known as a Paul ion trap, and discuss how this multi-disciplinary technique is being used to address some of the most challenging questions in the field of intense particle beam dynamics.
WEA2WA04 Space-Charge Compensation Using Electron Columns at IOTA -1
  • B.T. Freemire
    Northern Illinois University, DeKalb, Illinois, USA
  • S. Chattopadhyay
    Northern Illinois Univerity, DeKalb, Illinois, USA
  • M. Chung
    UNIST, Ulsan, Republic of Korea
  • C.S. Parkpresenter, V.D. Shiltsev, G. Stancari
    Fermilab, Batavia, Illinois, USA
  • G. Penn
    LBNL, Berkeley, California, USA
  Funding: US Department of Energy contracts DE-AC02-07CH11359 and DE-AC02-05CH1123 and the GARD Program.
Beam loss due to space charge is a major problem at current and future high intensity particle accelerators. The space charge force can be compensated for proton or ion beams by creating a column of electrons with a charge distribution matched to that of the beam, maintaining electron-proton stability. The column is created by the beam ionizing short sections of high pressure gas. The ionization electrons are then shaped appropriately using electric and magnetic fields. The Integrable Optics Test Accelerator (IOTA) at Fermilab is a test bed for beam loss and instability mitigation techniques. Simulations using the particle-in-cell code, Warp, have been made to track the evolution of both the electron column and the beam over multiple passes. A 2.5 MeV proton beamline is under construction at IOTA, to be used to study the effect of the electron column on a space charge dominated beam.
slides icon Slides WEA2WA04 [8.501 MB]