HB2016 - List of Authors (Plum, M.A.)

Paper	Title	Page
TUPM6X01	H⁻ Charge Exchange Injection Issues at High Power	304
	M.A. Plum ORNL, Oak Ridge, Tennessee, USA
	At low beam powers H− charge exchange injection into a storage ring or synchrotron is relatively simple. A thin stripper foil removes the two “convoy” electrons from the H− particle and the newly-created proton begins to circulate around the ring. At high beam powers there are complications due to the heat created in the stripper foil, the power in the H⁰ excited states, and the power in the convoy electrons. The charge-exchanged beam power at the Oak Ridge Spallation Neutron Source is the highest in the world. Although the SNS ring was carefully designed to operate at this level there have been surprises, primarily involving the convoy electrons. Examples include damage to the foil brackets due to reflected convoy electrons and damage to the electron collector due to the primary convoy electrons. The SNS Second Target Station project calls for doubling the beam power and thus placing even more stress on the charge-exchange-injection beam-line components. In this presentation we will compare charge-exchange-injection designs at high-power facilities around the world, discuss lessons learned, and describe the future plans at SNS.
	Slides TUPM6X01 [10.929 MB]
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WEPM2Y01	Model Benchmark With Experiment at the SNS Linac	439
	A.P. Shishlo, A.V. Aleksandrov, M.A. Plum ORNL, Oak Ridge, Tennessee, USA Y. Liu ORNL RAD, Oak Ridge, Tennessee, USA
	Funding: ORNL/SNS is managed by UT-Battelle, LLC, for the U.S. Department of Energy under contract DE-AC05-00OR22725. The history of attempts to perform a transverse matching in the SNS superconducting linac (SCL) is discussed. The SCL has 9 laser wire (LW) stations to perform nondestructive measurements of the transverse beam profiles. Any matching starts with the measurement of the initial Twiss parameters which in the SNS case was done by using the first four LW stations at the beginning of the superconducting linac. For years the consistency between all LW stations data could not be achieved. This problem was resolved only after significant improvements in accuracy of the phase scans of the SCL cavities, more precise analysis of all available scan data, better optics planning, and the initial longitudinal Twiss parameters measurements. The presented paper discusses in details these developed procedures.
	Slides WEPM2Y01 [2.815 MB]
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Paper

Title

Page

H⁻ Charge Exchange Injection Issues at High Power

304

M.A. Plum
ORNL, Oak Ridge, Tennessee, USA

At low beam powers H− charge exchange injection into a storage ring or synchrotron is relatively simple. A thin stripper foil removes the two “convoy” electrons from the H− particle and the newly-created proton begins to circulate around the ring. At high beam powers there are complications due to the heat created in the stripper foil, the power in the H⁰ excited states, and the power in the convoy electrons. The charge-exchanged beam power at the Oak Ridge Spallation Neutron Source is the highest in the world. Although the SNS ring was carefully designed to operate at this level there have been surprises, primarily involving the convoy electrons. Examples include damage to the foil brackets due to reflected convoy electrons and damage to the electron collector due to the primary convoy electrons. The SNS Second Target Station project calls for doubling the beam power and thus placing even more stress on the charge-exchange-injection beam-line components. In this presentation we will compare charge-exchange-injection designs at high-power facilities around the world, discuss lessons learned, and describe the future plans at SNS.

Slides TUPM6X01 [10.929 MB]

Export •

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

WEPM2Y01

Model Benchmark With Experiment at the SNS Linac

439

A.P. Shishlo, A.V. Aleksandrov, M.A. Plum
ORNL, Oak Ridge, Tennessee, USA
Y. Liu
ORNL RAD, Oak Ridge, Tennessee, USA

Funding: ORNL/SNS is managed by UT-Battelle, LLC, for the U.S. Department of Energy under contract DE-AC05-00OR22725.
The history of attempts to perform a transverse matching in the SNS superconducting linac (SCL) is discussed. The SCL has 9 laser wire (LW) stations to perform nondestructive measurements of the transverse beam profiles. Any matching starts with the measurement of the initial Twiss parameters which in the SNS case was done by using the first four LW stations at the beginning of the superconducting linac. For years the consistency between all LW stations data could not be achieved. This problem was resolved only after significant improvements in accuracy of the phase scans of the SCL cavities, more precise analysis of all available scan data, better optics planning, and the initial longitudinal Twiss parameters measurements. The presented paper discusses in details these developed procedures.

Slides WEPM2Y01 [2.815 MB]

Export •

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