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Title: Implementation of Maxwell's equations in the reconstruction of the magnetic field in the g -2 storage ring

Journal Article · · Journal of Instrumentation
 [1];  [2];  [3]
  1. Argonne National Lab. (ANL), Argonne, IL (United States). Dept. of High Energy Physics
  2. Technische Universität München, Garching (Germany). Physik-Dept.
  3. European Organization for Nuclear Research (CERN), Geneva (Switzerland). Theory Dept.

We present a method for implementing the constraints that are implied by Maxwell's equations in fits to measurements of the magnetic field in the muon storage ring of the $g - 2$ experiment. The method that we use makes use of toroidal-harmonic solutions of Laplace's equation. We point out that the fitting problem can be approximated well as a linear-algebra problem. We have devised an efficient algorithm for the linear-algebra problem that makes it possible to find a solution for 105 data points and 104 harmonics in less than an hour on a present-day desktop computer. We illustrate our method by applying it to some preliminary measurements of the magnetic field in the $g - 2$ storage ring.

Research Organization:
Argonne National Laboratory (ANL), Argonne, IL (United States)
Sponsoring Organization:
Alexander von Humboldt Foundation, Bonn (Germany); USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
Grant/Contract Number:
AC02-06CH11357
OSTI ID:
1559865
Alternate ID(s):
OSTI ID: 22895944
Journal Information:
Journal of Instrumentation, Journal Name: Journal of Instrumentation Journal Issue: 07 Vol. 14; ISSN 1748-0221
Publisher:
Institute of Physics (IOP)Copyright Statement
Country of Publication:
United States
Language:
English

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On best approximate solutions of linear matrix equations journal January 1956
On Toroidal Functions journal October 1893