High Energy High Intensity Hadron Beams EXPERIMENTS ON LHC LONG-RANGE BEAM-BEAM COMPENSATION IN THE CERN SPS (original) (raw)
Related papers
2024
In high intensity and high energy colliders, such as the CERN Large Hadron Collider (LHC) and its future high-luminosity upgrade, interactions between the two beams around the different interaction points impose machine performance limitations. In fact, their effect reduces the beam lifetime, and therefore, the collider's luminosity reach. Those interactions are called beam-beam long-range (BBLR) interactions, and a possible mitigation of their effect using dc wires was proposed for the first time in the early 2000's. This solution is currently being studied as an option for enhancing the HL-LHC performance. In 2017 and 2018, four demonstrators of wire compensators have been installed in the LHC. A 2-yearlong experimental campaign followed in order to validate the possibility to mitigate the BBLR interactions in the LHC. During this campaign, a proof-of-concept was completed and motivated an additional set of experiments, successfully demonstrating the mitigation of BBLR interactions effects in beam conditions compatible with the operational configuration. This paper reports in detail the preparation of the experimental campaign, including the corresponding tracking simulations and the obtained results, and draws some perspectives for the future.
Compensation of long-range beam-beam interaction at the CERN LHC
2008
Charged particle beams in high energy, high luminosity particle colliders are accompanied by strong and highly nonlinear electromagnetic fields. When two counterrotating beams pass each other these fields give rise to so called ``beam-beam interactions'' with a wide spectrum of negative consequences for the beam dynamics resulting e.g. in particle loss and emittance blow up. In the Large Hadron Collider (LHC) such crossings will occur each turn four times ``head-on'' (once at each interaction point, IP) and fifteen times ``long-range'' on each side of each IP with a small transverse offset. In order to correct for the resulting perturbations a wire compensator is foreseen. In the framework of this thesis the tracking code ``BBTrack'' has been developed and employed to investigate long-range beam-beam interaction and its wire compensation in the CERN LHC (nominal and upgraded). Complementary experimental studies at RHIC at BNL and the CERN SPS ...
Simulation studies for LHC long-range beam-beam compensators
The performance of the Large Hadron Collider (LHC) and its minimum crossing angle are limited by long-range beam-beam collisions. Wire compensators can mitigate part of the long-range effects and may allow for smaller crossing angles, smaller β*, or higher beam intensity. A prototype long-range wire compensator should be installed in the LHC by 2014/15. We report simulation studies examining and comparing the efficiency of the wire compensation, in terms of tune footprint or dynamic aperture, at various candidate locations, with different wire shapes, and for varying transverse distance from the beam.
First Results of the Compensation of the Beam-Beam Effect with DC Wires in the LHC
2019
The compensation of the long-range beam-beam interactions using DC wires is presently under study as an option for enhancing the machine performance in the frame of the High-Luminosity LHC project (HL-LHC). The original idea dates back more than 15 years. After the installation of four wire prototypes in the LHC in 2018, a successful experimental campaign was performed during the last months. The experimental setup and the main results are reported in this paper.
Simulation studies for the LHC long-range beam-beam compensators
2012
The performance of the Large Hadron Collider (LHC) and its minimum crossing angle are limited by long-range beam-beam collisions. Wire compensators can mitigate part of the long-range effects and may allow for smaller crossing angles, smaller β∗, or higher beam intensity. A prototype long-range wire compensator should be installed in the LHC by 2014/15. We report simulation studies examining and comparing the efficiency of the wire compensation, in terms of tune footprint or dynamic aperture, at various candidate locations, with different wire shapes, and for varying transverse distance from the beam.
Experiments on LHC Long-Range Beam-Beam Compensation and Crossing Schemes at the CERN SPS in 2004
2005
Experiments with two prototype long-range beam-beam compensators (current-carrying wires) during the 2004 CERN SPS run explored the efficiency of a proposed longrange beam-beam compensation for the LHC. In addition, the SPS compensators were also used to "simulate" the effect of different planes of crossing at two LHC interaction points. We present the experimental results and compare them with computer simulations.
JACoW : Progress with Long-Range Beam-Beam Compensation Studies for High Luminosity LHC
2017
Long-range beam-beam (LRBB) interactions can be a source of emittance growth and beam losses in the LHC during physics and will become even more relevant with the smaller β* and higher bunch intensities foreseen for the High Luminosity LHC upgrade (HL-LHC), in particular if operated without crab cavities. Both beam losses and emittance growth could be mitigated by compensating the non-linear LRBB kick with a correctly placed current carrying wire. Such a compensation scheme is currently being studied in the LHC through a demonstration test using current-bearing wires embedded into collimator jaws, installed either side of the high luminosity interaction regions. For HL-LHC two options are considered, a current-bearing wire as for the demonstrator, or electron lenses, as the ideal distance between the particle beam and compensating current may be too small to allow the use of solid materials. This paper reports on the ongoing activities for both options, covering the progress of the wire-in-jaw collimators, the foreseen LRBB experiments at the LHC, and first considerations for the design of the electron lenses to ultimately replace material wires for HL-LHC.
LHC beam-beam compensation using wires and electron lenses
2007 IEEE Particle Accelerator Conference (PAC), 2007
We present weak-strong simulation results for a possible application of current-carrying wires and electron lenses to compensate the LHC long-range and head-on beambeam interaction, respectively, for nominal and PACMAN bunches. We show that these measures have the potential to considerably increase the beam-beam limit, allowing for a corresponding increase in peak luminosity
MD2202: compensating long-range beam-beam effect in the LHC using DC wires
2019
G. Sterbini, D. Amorim, G. Arduini, H. Bartosik, R. Bruce, X. Buffat, L. Carver, G. Cattenoz, E. Effinger, S. Fartoukh, M. Fitterer, N. Fuster-Martinez, M. Gasior, M. Gonzalez-Berges, A. Gorzawski, G.-H. Hemelsoet, M. Hostettler, G. Iadarola, R. Jones, D. Kaltchev, N. Karastathis, S. Kostoglou, I. Lamas-Garcia, T. Levens, A. Levichev, L. E. Medina-Medrano, D. Mirarchi, J. Olexa, P. S. Papadopoulou, Y. Papaphilippou, D. Pellegrini, M. Pojer, L. Ponce, A. Poyet, S. Redaelli, A. Rossi, B. M. Salvachua Ferrando, H. Schmickler, F. Schmidt, K. Skoufaris, M. Solfaroli Camillocci, R. Tomás-Garcia, G. Trad, A. Valishev, D. Valuch, C. Xu, C. Zamantzas, P. Zisopoulos. CERN, CH-1211 Geneva, Switzerland
Feasibility Study of Beam-Beam Compensation in the Tevatron with Wires
2005
We explore the possibility of compensating long-range beam-beam interactions in the Tevatron by current carrying wires. Compensation strategies depend on whether the compensation is done close to the interaction or nonlocally, on the aspect ratio of the strong beam and on other details. Strategies for each case have been developed and applied to the Tevatron. We discuss the results of these strategies at injection and collision energy.