IPAC2015 - List of Authors (Lund, S.M.)

Paper	Title	Page
MOPWI026	Transverse Matching of Horizontal-Vertical Coupled Beams for the FRIB Linac	1211
	Y. Zhang, P. Chu, Z.Q. He, S.M. Lund, D.G. Maxwell FRIB, East Lansing, Michigan, USA
	Funding: Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661 FRIB driver linac will deliver all heavy ion beams up to uranium with energy above 200 MeV/u, and maximum beam power on target 400 kW for nuclear physics research. Strong horizontal-vertical beam coupling exists in the FRIB linac since superconducting solenoids are applied to focus multi charge state beams. Further, the FRIB low beta SRF cavities have raised quadrupole field components. The combined effects make beam transverse matching challenging. In this paper, we study transverse matching of horizontal-vertical coupled beams based on beam profile measurements with multiple wire scanners. There are multiple solutions for the initial linac beams with coupling, and errors of the beam diagnostics and magnet power supplies introduce further complication. Nonetheless, simulation studies show that satisfactory transverse matching can be achieved with proper linac beam tuning.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOPWI026
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THPF139	Nonlinear Optics of Solenoid Magnets	4048
	S.M. Lund FRIB, East Lansing, Michigan, USA
	Funding: Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661 and the National Science Foundation under Grant No. PHY-1102511. Solenoid magnets are often employed for focusing in low energy beam transport lattices in the front-end of a machine. We derive a relatively simple analytic formula for the nonlinear angular focusing kick imparted to particles traversing the solenoid. Few approximations are made. The formula suggests that for beam transport, little can be done to reduce nonlinearities in solenoid-type magnets other than take a simple design without abrupt changes as a function of axial coordinate and appropriately choose the aspect ratio (characteristic bore radius over axial length) of the magnet system and the beam filling factor within the aperture to limit nonlinear effects. Illustrative applications of the formula characterize nonlinear focusing effects in iron-free and iron type solenoid magnets.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-THPF139
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Transverse Matching of Horizontal-Vertical Coupled Beams for the FRIB Linac

1211

Y. Zhang, P. Chu, Z.Q. He, S.M. Lund, D.G. Maxwell
FRIB, East Lansing, Michigan, USA

Funding: Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661
FRIB driver linac will deliver all heavy ion beams up to uranium with energy above 200 MeV/u, and maximum beam power on target 400 kW for nuclear physics research. Strong horizontal-vertical beam coupling exists in the FRIB linac since superconducting solenoids are applied to focus multi charge state beams. Further, the FRIB low beta SRF cavities have raised quadrupole field components. The combined effects make beam transverse matching challenging. In this paper, we study transverse matching of horizontal-vertical coupled beams based on beam profile measurements with multiple wire scanners. There are multiple solutions for the initial linac beams with coupling, and errors of the beam diagnostics and magnet power supplies introduce further complication. Nonetheless, simulation studies show that satisfactory transverse matching can be achieved with proper linac beam tuning.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOPWI026

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPF139

Nonlinear Optics of Solenoid Magnets

4048

S.M. Lund
FRIB, East Lansing, Michigan, USA

Funding: Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661 and the National Science Foundation under Grant No. PHY-1102511.
Solenoid magnets are often employed for focusing in low energy beam transport lattices in the front-end of a machine. We derive a relatively simple analytic formula for the nonlinear angular focusing kick imparted to particles traversing the solenoid. Few approximations are made. The formula suggests that for beam transport, little can be done to reduce nonlinearities in solenoid-type magnets other than take a simple design without abrupt changes as a function of axial coordinate and appropriately choose the aspect ratio (characteristic bore radius over axial length) of the magnet system and the beam filling factor within the aperture to limit nonlinear effects. Illustrative applications of the formula characterize nonlinear focusing effects in iron-free and iron type solenoid magnets.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-THPF139

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)