Ecloud Build-Up Simulations for the FNAL MI for a Mixed Fill Pattern: Dependence on Peak SEY and Pulse Intensity During the Ramp
Abstract
We present simulation results of the build-up of the electron-cloud density n{sub e} in three regions of the FNAL Main Injector (MI) for a beam fill pattern made up of 5 double booster batches followed by a 6th single batch. We vary the pulse intensity in the range N{sub t} = (2-5) x 10{sup 13}, and the beam kinetic energy in the range E{sub k} = 8-120 GeV. We assume a secondary electron emission model qualitatively corresponding to TiN, except that we let the peak value of the secondary electron yield (SEY) {delta}{sub max} vary as a free parameter in a fairly broad range. Our main conclusions are: (1) At fixed N{sub t} there is a clear threshold behavior of n{sub e} as a function of {delta}{sub max} in the range {approx} 1.1-1.3. (2) At fixed {delta}{sub max}, there is a threshold behavior of n{sub e} as a function of N{sub t} provided {delta}{sub max} is sufficiently high; the threshold value of N{sub t} is a function of the characteristics of the region being simulated. (3) The dependence on E{sub k} is weak except possibly at transition energy. Most of these results were informally presented to the relevant MI personnelmore »
- Authors:
- Publication Date:
- Research Org.:
- Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
- Sponsoring Org.:
- Accelerator& Fusion Research Division
- OSTI Identifier:
- 1004604
- Report Number(s):
- LBNL-4215E
TRN: US1101051
- DOE Contract Number:
- DE-AC02-05CH11231
- Resource Type:
- Technical Report
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 70; ELECTRON EMISSION; ELECTRONS; KINETIC ENERGY; PERSONNEL; SIMULATION
Citation Formats
Furman, M A. Ecloud Build-Up Simulations for the FNAL MI for a Mixed Fill Pattern: Dependence on Peak SEY and Pulse Intensity During the Ramp. United States: N. p., 2010.
Web. doi:10.2172/1004604.
Furman, M A. Ecloud Build-Up Simulations for the FNAL MI for a Mixed Fill Pattern: Dependence on Peak SEY and Pulse Intensity During the Ramp. United States. https://doi.org/10.2172/1004604
Furman, M A. 2010.
"Ecloud Build-Up Simulations for the FNAL MI for a Mixed Fill Pattern: Dependence on Peak SEY and Pulse Intensity During the Ramp". United States. https://doi.org/10.2172/1004604. https://www.osti.gov/servlets/purl/1004604.
@article{osti_1004604,
title = {Ecloud Build-Up Simulations for the FNAL MI for a Mixed Fill Pattern: Dependence on Peak SEY and Pulse Intensity During the Ramp},
author = {Furman, M A},
abstractNote = {We present simulation results of the build-up of the electron-cloud density n{sub e} in three regions of the FNAL Main Injector (MI) for a beam fill pattern made up of 5 double booster batches followed by a 6th single batch. We vary the pulse intensity in the range N{sub t} = (2-5) x 10{sup 13}, and the beam kinetic energy in the range E{sub k} = 8-120 GeV. We assume a secondary electron emission model qualitatively corresponding to TiN, except that we let the peak value of the secondary electron yield (SEY) {delta}{sub max} vary as a free parameter in a fairly broad range. Our main conclusions are: (1) At fixed N{sub t} there is a clear threshold behavior of n{sub e} as a function of {delta}{sub max} in the range {approx} 1.1-1.3. (2) At fixed {delta}{sub max}, there is a threshold behavior of n{sub e} as a function of N{sub t} provided {delta}{sub max} is sufficiently high; the threshold value of N{sub t} is a function of the characteristics of the region being simulated. (3) The dependence on E{sub k} is weak except possibly at transition energy. Most of these results were informally presented to the relevant MI personnel in April 2010.},
doi = {10.2172/1004604},
url = {https://www.osti.gov/biblio/1004604},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sat Dec 11 00:00:00 EST 2010},
month = {Sat Dec 11 00:00:00 EST 2010}
}