Longitudinal motion of the beam in the Fermilab booster

Title: Longitudinal motion of the beam in the Fermilab booster

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Abstract

When the Fermilab Booster Accelerator is operated at or above 1.5 x 10/sup 12/ protons per pulse (extraction current about 155 mA) large amplitude coupled bunch longitudinal dipole oscillations occur between transition and extraction times. The oscillations do not contribute to beam loss in the booster but, because the beam is transferred synchronously into preexisting buckets in the Main Ring, the oscillations contribute to a deterioration of beam quality in the main ring. Two mode numbers have been established for the instabilities and the primary source frequencies have been isolated, although the offending objects have not. Operation of one of the eighteen accelerating cavities at a harmonic number one unit lower than the operating value (83 instead of 84) effectively damps the motion by the introduction bunch to bunch synchrotron tune spread.

Authors:: Ankenbrandt, C M; Griffin, J E; Johnson, R P; Lackey, J; Meisner, K

Publication Date:: 1977-01-01

Research Org.:: Fermi National Accelerator Lab., Batavia, IL (USA)

OSTI Identifier:: 7307593

Report Number(s):: CONF-770313-108
TRN: 77-013182

DOE Contract Number:: EY-76-C-02-3000

Resource Type:: Conference

Resource Relation:: Conference: Particle accelerator conference, Chicago, IL, USA, 16 Mar 1977

Country of Publication:: United States

Language:: English

Subject:: 43 PARTICLE ACCELERATORS; FERMILAB ACCELERATOR; BEAM DYNAMICS; BEAM BUNCHING; DAMPING; INSTABILITY; OSCILLATIONS; PARTICLE BOOSTERS; ACCELERATORS; CYCLIC ACCELERATORS; SYNCHROTRONS; 430200* - Particle Accelerators- Beam Dynamics, Field Calculations, & Ion Optics

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                    Ankenbrandt, C M, Griffin, J E, Johnson, R P, Lackey, J, and Meisner, K. Longitudinal motion of the beam in the Fermilab booster.  United States: N. p., 1977. 
        Web.

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                    Ankenbrandt, C M, Griffin, J E, Johnson, R P, Lackey, J, & Meisner, K. Longitudinal motion of the beam in the Fermilab booster.  United States.

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                    Ankenbrandt, C M, Griffin, J E, Johnson, R P, Lackey, J, and Meisner, K. Sat .  
        "Longitudinal motion of the beam in the Fermilab booster".  United States.  https://www.osti.gov/servlets/purl/7307593.

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@article{osti_7307593,

  title        = {Longitudinal motion of the beam in the Fermilab booster},

  author       = {Ankenbrandt, C M and Griffin, J E and Johnson, R P and Lackey, J and Meisner, K},

  abstractNote = {When the Fermilab Booster Accelerator is operated at or above 1.5 x 10/sup 12/ protons per pulse (extraction current about 155 mA) large amplitude coupled bunch longitudinal dipole oscillations occur between transition and extraction times. The oscillations do not contribute to beam loss in the booster but, because the beam is transferred synchronously into preexisting buckets in the Main Ring, the oscillations contribute to a deterioration of beam quality in the main ring. Two mode numbers have been established for the instabilities and the primary source frequencies have been isolated, although the offending objects have not. Operation of one of the eighteen accelerating cavities at a harmonic number one unit lower than the operating value (83 instead of 84) effectively damps the motion by the introduction bunch to bunch synchrotron tune spread.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/7307593},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {1977},

  month        = {1}

}

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