IPAC2015 - List of Authors (Kahn, S.A.)

Paper	Title	Page
TUPTY074	Muon Beam Emittance Evolution in the Helical Ionization Cooling Channel for Bright Muon Sources	2203
	K. Yonehara, C.Y. Yoshikawa Fermilab, Batavia, Illinois, USA C.M. Ankenbrandt, R.P. Johnson, S.A. Kahn Muons, Inc, Illinois, USA M. Chung UNIST, Ulsan, Republic of Korea Y.S. Derbenev, A.V. Sy JLab, Newport News, Virginia, USA B.T. Freemire IIT, Chicago, Illinois, USA
	The six-dimensional ionization cooling is essential to design a bright muon source. A geometry constraint is a challenge issue in a compact helical cooling channel (HCC). Especially, the HCC requires a large bore helical magnet and a compact helical RF system to incorporate the RF into the magnet chamber. A new emittance evolution has been designed to mitigate the geometry constraint. The HCC was functionally separated into three parts sections. The lattice at the initial section provides a large transverse acceptance by using a strong helical focus magnet. Once the transverse beam size is small enough to get into the compact RF the HCC lattice in the middle section generates a large longitudinal beta tune to dominate the longitudinal cooling. Consequently, the longitudinal emittance becomes smaller than the transverse one at the end of middle section. In the final section, the magnetic field strength is gradually reduced to match out the helical channel to the straight solenoid. As a result, the emittance exchange takes place and the final transverse emittance becomes smaller than the longitudinal one. The new emittance evolution scenario will be discussed in this presentation.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-TUPTY074
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WEPTY059	Alternative Methods for Field Corrections in Helical Solenoids	3409
	K.E. Melconian Texas A&M University, College Station, Texas, USA G. Flanagan, S.A. Kahn Muons, Inc, Illinois, USA S. Krave, M.L. Lopes, J.C. Tompkins, K. Yonehara Fermilab, Batavia, Illinois, USA
	Funding: Fermi Research Alliance under DOE Contract DE-AC02-07CH11359 Helical cooling channels have been proposed for highly efficient 6D muon cooling. Helical solenoids produce solenoidal, helical dipole, and helical gradient field components. Previous studies explored the geometric tunability limits on these main field components. In this paper we present two alternative correction schemes, tilting the solenoids and the addition of helical lines, to reduce the required strength of the anti-solenoid and add an additional tuning knob.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPTY059
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WEPTY064	Thermal-mechanical Analysis of the FRIB Nuclear Fragment Separator Dipole Magnet	3425
	S.A. Kahn, A. Dudas, G. Flanagan Muons, Inc, Illinois, USA R.C. Gupta BNL, Upton, Long Island, New York, USA
	Funding: This work was supported by the U.S. Department of Energy under Grant DE-SC-0006273 Dipole magnets in the fragment separator region of the Facility for Rare Isotope Beams (FRIB) are critical elements used to select the desired isotopes. These magnets are subjected to high radiation and heat loads. High temperature superconductors (HTS), which have been shown to be radiation resistant and can operate at 40 K where heat removal is substantially more efficient than 4.5 K where conventional superconductors such as NbTi and Nb3Sn operate, are proposed for the coils. The magnet coils carry large current and will be subjected to large Lorentz forces that must be constrained to avoid distortions of the coils. It is desirable to minimize the use of organic materials in the fabrication of this magnet because of the radiation environment. This paper will describe an approach to support the coils to minimize coil deformation and cryogenic heat loss.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPTY064
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Paper

Title

Page

Muon Beam Emittance Evolution in the Helical Ionization Cooling Channel for Bright Muon Sources

2203

K. Yonehara, C.Y. Yoshikawa
Fermilab, Batavia, Illinois, USA
C.M. Ankenbrandt, R.P. Johnson, S.A. Kahn
Muons, Inc, Illinois, USA
M. Chung
UNIST, Ulsan, Republic of Korea
Y.S. Derbenev, A.V. Sy
JLab, Newport News, Virginia, USA
B.T. Freemire
IIT, Chicago, Illinois, USA

The six-dimensional ionization cooling is essential to design a bright muon source. A geometry constraint is a challenge issue in a compact helical cooling channel (HCC). Especially, the HCC requires a large bore helical magnet and a compact helical RF system to incorporate the RF into the magnet chamber. A new emittance evolution has been designed to mitigate the geometry constraint. The HCC was functionally separated into three parts sections. The lattice at the initial section provides a large transverse acceptance by using a strong helical focus magnet. Once the transverse beam size is small enough to get into the compact RF the HCC lattice in the middle section generates a large longitudinal beta tune to dominate the longitudinal cooling. Consequently, the longitudinal emittance becomes smaller than the transverse one at the end of middle section. In the final section, the magnetic field strength is gradually reduced to match out the helical channel to the straight solenoid. As a result, the emittance exchange takes place and the final transverse emittance becomes smaller than the longitudinal one. The new emittance evolution scenario will be discussed in this presentation.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-TUPTY074

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WEPTY059

Alternative Methods for Field Corrections in Helical Solenoids

3409

K.E. Melconian
Texas A&M University, College Station, Texas, USA
G. Flanagan, S.A. Kahn
Muons, Inc, Illinois, USA
S. Krave, M.L. Lopes, J.C. Tompkins, K. Yonehara
Fermilab, Batavia, Illinois, USA

Funding: Fermi Research Alliance under DOE Contract DE-AC02-07CH11359
Helical cooling channels have been proposed for highly efficient 6D muon cooling. Helical solenoids produce solenoidal, helical dipole, and helical gradient field components. Previous studies explored the geometric tunability limits on these main field components. In this paper we present two alternative correction schemes, tilting the solenoids and the addition of helical lines, to reduce the required strength of the anti-solenoid and add an additional tuning knob.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPTY059

Export •

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

WEPTY064

Thermal-mechanical Analysis of the FRIB Nuclear Fragment Separator Dipole Magnet

3425

S.A. Kahn, A. Dudas, G. Flanagan
Muons, Inc, Illinois, USA
R.C. Gupta
BNL, Upton, Long Island, New York, USA

Funding: This work was supported by the U.S. Department of Energy under Grant DE-SC-0006273
Dipole magnets in the fragment separator region of the Facility for Rare Isotope Beams (FRIB) are critical elements used to select the desired isotopes. These magnets are subjected to high radiation and heat loads. High temperature superconductors (HTS), which have been shown to be radiation resistant and can operate at 40 K where heat removal is substantially more efficient than 4.5 K where conventional superconductors such as NbTi and Nb3Sn operate, are proposed for the coils. The magnet coils carry large current and will be subjected to large Lorentz forces that must be constrained to avoid distortions of the coils. It is desirable to minimize the use of organic materials in the fabrication of this magnet because of the radiation environment. This paper will describe an approach to support the coils to minimize coil deformation and cryogenic heat loss.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPTY064

Export •

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