dorsal/arxiv
View SchemaNonlinear $\delta f$ Method for Beam-Beam Simulation
| Authors | Yunhai Cai, Alexander W. Chao, Stephan I. Tzenov, Toshi Tajima |
|---|---|
| Categories | |
| ArXiv ID | physics/0010055 |
| URL | https://arxiv.org/abs/physics/0010055 |
Abstract
We have developed an efficacious algorithm for simulation of the beam-beam interaction in synchrotron colliders based on the nonlinear $\delta f$ method, where $\delta f$ is the much smaller deviation of the beam distribution from the slowly evolving main distribution $f_0$. In the presence of damping and quantum fluctuations of synchrotron radiation it has been shown that the slowly evolving part of the distribution function satisfies a Fokker-Planck equation. Its solution has been obtained in terms of a beam envelope function and an amplitude of the distribution, which satisfy a coupled system of ordinary differential equations. A numerical algorithm suited for direct code implementation of the evolving distributions for both $\delta f$ and $f_0$ has been developed. Explicit expressions for the dynamical weights of macro-particles for $\delta f$ as well as an expression for the slowly changing $f_0$ have been obtained.
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"abstract": "We have developed an efficacious algorithm for simulation of the beam-beam\ninteraction in synchrotron colliders based on the nonlinear $\\delta f$ method,\nwhere $\\delta f$ is the much smaller deviation of the beam distribution from\nthe slowly evolving main distribution $f_0$. In the presence of damping and\nquantum fluctuations of synchrotron radiation it has been shown that the slowly\nevolving part of the distribution function satisfies a Fokker-Planck equation.\nIts solution has been obtained in terms of a beam envelope function and an\namplitude of the distribution, which satisfy a coupled system of ordinary\ndifferential equations. A numerical algorithm suited for direct code\nimplementation of the evolving distributions for both $\\delta f$ and $f_0$ has\nbeen developed. Explicit expressions for the dynamical weights of\nmacro-particles for $\\delta f$ as well as an expression for the slowly changing\n$f_0$ have been obtained.",
"arxiv_id": "physics/0010055",
"authors": [
"Yunhai Cai",
"Alexander W. Chao",
"Stephan I. Tzenov",
"Toshi Tajima"
],
"categories": [
"physics.acc-ph",
"physics.comp-ph"
],
"title": "Nonlinear $\\delta f$ Method for Beam-Beam Simulation",
"url": "https://arxiv.org/abs/physics/0010055"
},
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