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  • Open Access

Simulations of coherent beam-beam modes at the Large Hadron Collider

M. P. Zorzano and F. Zimmermann

  • CERN, SL Division (AP), CH-1211 Geneva 23, Switzerland

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Phys. Rev. ST Accel. Beams 3, 044401 – Published 26 April, 2000

DOI: https://doi.org/10.1103/PhysRevSTAB.3.044401

Abstract

The transverse coherent motion of two colliding proton beams at the Large Hadron Collider is studied by multiparticle tracking. We use the beam-beam force for a Gaussian beam distribution with variable barycenters and rms beam sizes, and optionally include the effect of long-range collisions and external impedance. The simulation yields the coherent and incoherent oscillation frequencies, the emittance growth of either beam, and evidence for the existence or lack of Landau damping. For head-on collisions of beams with equal sizes, we find that the π-mode frequency lies outside of the continuum frequency spread, if the ratio of the beam-beam parameters exceeds 0.6, in accordance with predictions. For smaller ratios of the beam-beam parameters, or if, for equal beam-beam parameters, the beam sizes are widely different, the π mode is Landau damped. When long-range collisions are also included, undamped coherent modes do still exist outside the continuum, both with and without alternating crossing planes at two interaction points. However, separating the tunes of the two beams restores the Landau damping, provided the external impedance is sufficiently small.

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References (19)

  1. K. Yokoya and, H. Koiso, Part. Accel. 27, 181–186 (1990).
  2. A. W. Chao and R. D. Ruth, SLAC Report No. SLAC/AP-37, 1984.
  3. Proceedings of the Workshop on Beam-Beam Effects in Large Hadron Colliders, Geneva, 1999, J. Poole and F. Zimmermann (CERN Report No. CERN-SL-99-039 AP, 1999).
  4. Y. I. Alexahin, Part. Accel. 59, 43 (1999).
  5. A. Hofmann and O. Brüning, in Proceedings of the Workshop on Beam-Beam Effects in Large Hadron Colliders, Geneva, 1999 (Ref. [[3]]).
  6. A. Hofmann, in Proceedings of the Workshop on Beam-Beam Effects in Large Hadron Colliders, Geneva, 1999 (Ref. [[3]]).
  7. M. Bassetti and G. A. Erskine, CERN Report No. CERN-ISR-TH/80-06, 1980.
  8. M. Abramowitz and I. A. Stegun, Handbook of Mathematical Functions (Dover, New York, 1965), p. 297.
  9. E. Keil, Nucl. Instrum. Methods Phys. Res. 188, 9–14 (1981).
  10. S. Matsumoto and K. Hirata, KEK Report No. 92-146, 1992.
  11. W. Herr, CERN Report No. CERN-SL/91-34 (AP), LHC Note No. 165, 1991 .
  12. R. E. Meller and R. H. Siemann, IEEE Trans. Nucl. Sci. 28, No. 3, 2431–2433 (1981).
  13. M. P. Zorzano and F. Zimmermann, LHC Report No. 314, 1999.
  14. E. Keil, CERN-LEP-NOTE-294, 1981.
  15. L. Vos (private communication).
  16. W. Herr, CERN Report No. CERN SL/90-06 (AP), 1990.
  17. The SPEAR Group, R. H. Helm, M. J. Lee, M. Matera, P. L. Morton, J. M. Paterson, B. Richter, A. P. Sabersky, H. Wiedemann, P. B. Wilson, M. A. Allen, A. E. Augustin, and G. E. Fischer, in Proceedings of the IXth International Conference on High Energy Accelerators, 1974 (SLAC, Stanford, CA, 1974), p. 66.
  18. J. Gareyte, in Proceedings of the Workshop on Beam-Beam Effects in Large Hadron Colliders, Geneva, 1999 (Ref. [[3]]).
  19. F. Ruggiero, CERN Report No. CERN SL/95-09 (AP), LHC Note No. 313, 1995.

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Phys. Rev. ST Accel. Beams 3, 044401– Published 26 April, 2000
  • Received 31 January 2000
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This article is available under the terms of the Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.

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