Author: Miyamoto, R.
Paper Title Page
TUPPC081 First Experimental Observations from the LHC Dynamic Aperture Experiment 1362
 
  • M. Giovannozzi, M. Albert, G.E. Crockford, S.D. Fartoukh, W. Höfle, E.H. Maclean, A. Macpherson, L. Ponce, S. Redaelli, H. Renshall, F. Roncarolo, R.J. Steinhagen, E. Todesco, R. Tomás, W. Venturini Delsolaro
    CERN, Geneva, Switzerland
  • R. Miyamoto
    BNL, Upton, Long Island, New York, USA
 
  Following intensive numerical simulations to compute the dynamic aperture for the LHC in the design phase, the successful beam commissioning and the ensuing beam operations opened the possibility of performing beam measurements of the dynamics aperture. In this paper the experimental set-up and the first observations based on the few experimental sessions performed will be presented and discussed in detail.  
 
WEOBA02 Tevatron End-of-Run Beam Physics Experiments 2128
 
  • A. Valishev
    Fermilab, Batavia, USA
  • X. Gu, R. Miyamoto, S.M. White
    BNL, Upton, Long Island, New York, USA
  • J. Qiang
    LBNL, Berkeley, California, USA
  • F. Schmidt
    CERN, Geneva, Switzerland
 
  Funding: Fermi Research Alliance, LLC operates Fermilab under Contract DE-AC02-07CH11359 with the US Department of Energy. This work was partially supported by the US LHC Accelerator Research Program (LARP).
Before the Tevatron collider Run II ended in September of 2011, a two-week period was devoted to the experiments on various aspects of beam-beam interactions. The studied topics included offset collisions, coherent beam stability, effect of the bunch-length-to-beta-function ratio, and operation of AC dipole with colliding beams. In this report we summarize the results of beam experiments and supporting simulations.
 
slides icon Slides WEOBA02 [1.382 MB]  
 
MOPPC027 Synchro-Betatron Effects in the Presence of Large Piwinski Angle and Crab Cavities at the HL-LHC 190
 
  • S.M. White
    BNL, Upton, Long Island, New York, USA
  • R. Calaga
    CERN, Geneva, Switzerland
  • R. Miyamoto
    ESS, Lund, Sweden
 
  Funding: This work partially supported by the US Department of Energy through the US LHC Accelerator Research Program (LARP).
The reduction of beta-star at the collision points for the high luminosity LHC (HL-LHC) requires an increment in the crossing angle to maintain the normalized beam separation to suppress the effects of long-range beam-beam interactions. However, increase in crossing angle may give rise to synchro-betatron resonances which may negatively affect the beam emittance and lifetime. 6D weak-strong and strong-strong simulations are performed to study the effect of synchro-betatron resonances in the context of the HL-LHC layout and its suppression via crab crossing.
 
 
MOPPD076 Numerical Study of a Collimation System to Mitigate Beam Losses in the ESS Linac 541
 
  • R. Miyamoto, H. Danared, M. Eshraqi, A. Ponton
    ESS, Lund, Sweden
 
  The European Spallation Source (ESS) will be a 5 MW proton linac to produce spallation neutrons. A high power linac has a very low tolerance on beam losses, typically on the order of 1 W/m, to avoid activation of the linac components; hence, emittance and halo of the beam must be well controlled throughout the linac. A system of collimators in beam transport sections has been studied and tested as a means to mitigate the beam losses in several linacs. This paper presents the result of a numerical study of a collimation system for the ESS linac.  
 
MOPPR076 Using the BRAN Luminosity Detectors for Beam Emittance Monitoring During LHC Physics Runs 966
 
  • A. Ratti, H.S. Matis, M. Placidi, W.C. Turner
    LBNL, Berkeley, California, USA
  • E. Bravin
    CERN, Geneva, Switzerland
  • T.E. Lahey
    SLAC, Menlo Park, California, USA
  • E.S.M. McCrory
    Fermilab, Batavia, USA
  • R. Miyamoto
    ESS, Lund, Sweden
  • S.M. White
    BNL, Upton, Long Island, New York, USA
 
  Funding: This work partially supported by the US Department of Energy through the US LHC Accelerator Research Program (LARP).
The BRAN Ionization Chambers installed at the IP1 and IP5 Interaction Points of the LHC provide a relative measurement of the total and bunch-by-bunch luminosities. This information, combined with the logged bunch charges from a fast BCT monitor, offers the possibility of evaluating the Interaction Area in collision for each of the colliding bunch pairs and monitor its time evolution. A Graphic User Interface (GUI) has been implemented to display the interaction area of the proton bunches interacting in IP1 and IP5 during each of the Physics Runs in the attempt of displaying the contribution to the Luminosity time decay originating from possible emittance blow-up when operating the Accelerator close to the beam-beam limit. Early results confirm the ability to characterize the bunch by bunch emittance behavior during the store and study possible differences among bunches in the same fill.
 
 
TUPPR068 The Achromatic Telescopic Squeezing Scheme: Basic Principles and First Demonstration at the LHC 1978
 
  • S.D. Fartoukh, R. De Maria, B. Goddard, W. Höfle, M. Lamont, G.J. Müller, L. Ponce, S. Redaelli, R.J. Steinhagen, M. Strzelczyk, R. Tomás, G. Vanbavinckhove, J. Wenninger
    CERN, Geneva, Switzerland
  • R. Miyamoto
    ESS, Lund, Sweden
 
  The Achromatic Telescopic Squeezing (ATS) scheme [1] is a novel squeezing mechanism enabling the production of very low β* in circular colliders. The basic principles of the ATS scheme will be reviewed together with its strong justification for the High-Luminosity LHC Project. In this context, a few dedicated beam experiments were meticulously prepared and took place at the LHC in 2011. The results obtained will be highlighted, demonstrating already the potential of the ATS scheme for any upgrade project relying on a strong reduction of β*.
[1] S. Fartoukh, "An Achromatic Telescopic Squeezing (ATS) Scheme For The LHC Upgrade," IPAC'11, WEPC037, p. 2088 (2001).
 
 
THPPP046 ESS End-to-End Simulations: a Comparison Between IMPACT and MADX 3841
 
  • E. Laface, R. Miyamoto
    ESS, Lund, Sweden
  • D.C. Plostinar, C.R. Prior
    STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
 
  The European Spallation Source will be a 5 MW superconducting proton linac for the production of spallation neutrons. It is composed of an ion source, a radio frequency quadrupole, a drift tube linac and a superconducting linac as well as the low, medium and high, energy beam transport sections. At present these components of the linac are in the design phase: the optimization of the accelerator parameters requires an intensive campaign of simulations to test the model of the machine under possible operational conditions. In this paper the results of simulations performed with the IMPACT and MADX-PTC codes are presented and a comparison is made between them and independent simulations using TraceWin. The dynamics of the beam envelope and single and multi-particle tracking are reported.