IPAC2012 - List of Authors (Kahn, S.A.)

Paper	Title	Page
MOPPC037	Muon Collider Detector Backgrounds	211
	M.A.C. Cummings, S.A. Kahn Muons, Inc, Batavia, USA D. Hedin Northern Illinois University, DeKalb, Illinois, USA J.F. Kozminski Lewis University, Romeoville, Illinois, USA
	Funding: Supported in part by SBIR Grant 4738 · 10SC05447 Technological innovations in recent years have revived interest in muon colliders as the next generation energy frontier machine. Advances in muon cooling technology will make the focussing and acceleration of muons to TeV energies possible. The biggest challenge for muon colliders is that muons decay, but it is possible to build a large muon collider as a circular machine, even at multi-TeV energies, due to the greatly reduced synchrotron radiation expected from muons compared to electrons. The challenge for the detectors in such machines is overcoming the large backgrounds from muon decays in the colliding ring lattice that will inundate the interaction region (IR) and will make triggering and data reconstruction a challenge. Developing simulation tools that can reliably model the environment of the muon collider IR will be critical to physics analyses. We will need to expand the capabilities of current programs and use them to benchmark and verify results against each other. In this paper we will discuss these processes and calculate the resulting particle fluxes into the detector volume.

MOPPC038	Bethe-Heitler Muon Background at a Muon Collider	214
	S.A. Kahn, M.A.C. Cummings, T.J. Roberts Muons, Inc, Batavia, USA D. Hedin, A.O. Morris Northern Illinois University, DeKalb, Illinois, USA J.F. Kozminski Lewis University, Romeoville, Illinois, USA
	Multi-TeV muon colliders are an important option for a future energy frontier lepton collider since synchrotron radiation in a circular machine is significantly less than that in an electron collider. For a muon collider with 750 GeV μ+μ− with 2×10¹² μ per bunch we would expect 8.6×10⁵ muon decays per meter for the two beams. Muon decays are the source of beam induced backgrounds that can affect the physics. These backgrounds include electrons from muon decays, synchrotron radiation from the decay electrons, hadrons produced by photo-nuclear interactions, coherent and incoherent beam-beam pair production and Bethe-Heitler muon production. This paper will describe a simulation of the B-H muon pair production in a muon collider. These muons can penetrate the collider ring magnets and shielding and possibly enter into the detector regions. The simulation tracks B-H muons produced from electromagnetic shower interactions in collider ring material in the range of ±200 m from the interaction point.

THPPD042	High Radiation Environment Nuclear Fragment Separator Dipole Magnet	3605
	S.A. Kahn Muons, Inc, Batavia, USA R.C. Gupta BNL, Upton, Long Island, New York, USA
	Funding: Supported in part by STTR Grant 4746 · 11SC06273 Magnets in the fragment separator region of the Facility for Rare Isotope Beams (FRIB) would be subjected to extremely high radiation and heat loads. Critical elements of FRIB are the dipole magnets which select the desired isotopes. Since conventional NiTi and Nb3Sn superconductors must operate at ~4.5 K, the removal of the high heat load generated in these magnets with these superconductors would be difficult. The coils for these magnets must accommodate the large curvature from the 30° bend that the magnets subtend. High temperature superconductor (HTS) have been shown to be radiation resistant and can operate in the 20-50 K temperature range where heat removal is an order of magnitude more efficient than at 4.5 K. Furthermore these dipole magnets must be removable remotely for servicing because of the extremely high radiation environment. This paper will describe the magnetic and conceptual design of these magnets.

THPPD043	Radiation-tolerant Multipole Correction Coils for FRIB	3608
	S.A. Kahn Muons, Inc, Batavia, USA R.C. Gupta BNL, Upton, Long Island, New York, USA
	Multipole correction insert coils with significant field strength are required inside the large aperture superconducting quadrupole magnets in the fragment separator section of the Facility for Rare Isotope Beams (FRIB). Correction coils made with copper do not create the required field and conventional low temperature superconductors are not practical in the fragment separator magnets which will operate at 40-50 K. The correction coils should be made of HTS as the main quadrupole coils are. There is a significant advantage to using HTS in these coils as it can withstand the high radiation and heat load that will be present. This paper will describe an innovative design suitable for coils with the complex end geometry of cylindrical coils. We will look at the forces on the corrector coils from the mail quadrupole fields and anticipate possible coil distortions.

THPPD044	Fabrication and Testing of Curved Test Coil for FRIB Fragment Separator Dipole	3611
	S.A. Kahn Muons, Inc, Batavia, USA J. Escallier, R.C. Gupta, G. Jochen, Y. Shiroyanagi BNL, Upton, Long Island, New York, USA
	Funding: Supported in part by SBIR Grant 4746 · 11SC06273 A critical element of the fragment separator region of the Facility for Rare Isotope Beams (FRIB) is the 30° dipole bend magnet. Because this magnet will be subjected to extremely high radiation and heat loads, operation at 4.5 K would not be possible. High temperature superconductors which have been shown to be radiation resistant and can operated in the 30-50 K temperature range which is more effective for heat removal. An efficient design for this magnet would make use of coils that follow the curvature of the magnet. Winding curved coils with negative curvature are difficult as the coil tends to unwind during the process. As part of an R&D effort for this magnet we are winding a ¼ scale test coil for this magnet with YBCO conductor and are testing it at 77 K. This paper will discuss the winding process and the test results of this study.

Paper

Title

Page

Muon Collider Detector Backgrounds

211

M.A.C. Cummings, S.A. Kahn
Muons, Inc, Batavia, USA
D. Hedin
Northern Illinois University, DeKalb, Illinois, USA
J.F. Kozminski
Lewis University, Romeoville, Illinois, USA

Funding: Supported in part by SBIR Grant 4738 · 10SC05447
Technological innovations in recent years have revived interest in muon colliders as the next generation energy frontier machine. Advances in muon cooling technology will make the focussing and acceleration of muons to TeV energies possible. The biggest challenge for muon colliders is that muons decay, but it is possible to build a large muon collider as a circular machine, even at multi-TeV energies, due to the greatly reduced synchrotron radiation expected from muons compared to electrons. The challenge for the detectors in such machines is overcoming the large backgrounds from muon decays in the colliding ring lattice that will inundate the interaction region (IR) and will make triggering and data reconstruction a challenge. Developing simulation tools that can reliably model the environment of the muon collider IR will be critical to physics analyses. We will need to expand the capabilities of current programs and use them to benchmark and verify results against each other. In this paper we will discuss these processes and calculate the resulting particle fluxes into the detector volume.

MOPPC038

Bethe-Heitler Muon Background at a Muon Collider

214

S.A. Kahn, M.A.C. Cummings, T.J. Roberts
Muons, Inc, Batavia, USA
D. Hedin, A.O. Morris
Northern Illinois University, DeKalb, Illinois, USA
J.F. Kozminski
Lewis University, Romeoville, Illinois, USA

Multi-TeV muon colliders are an important option for a future energy frontier lepton collider since synchrotron radiation in a circular machine is significantly less than that in an electron collider. For a muon collider with 750 GeV μ+μ− with 2×10¹² μ per bunch we would expect 8.6×10⁵ muon decays per meter for the two beams. Muon decays are the source of beam induced backgrounds that can affect the physics. These backgrounds include electrons from muon decays, synchrotron radiation from the decay electrons, hadrons produced by photo-nuclear interactions, coherent and incoherent beam-beam pair production and Bethe-Heitler muon production. This paper will describe a simulation of the B-H muon pair production in a muon collider. These muons can penetrate the collider ring magnets and shielding and possibly enter into the detector regions. The simulation tracks B-H muons produced from electromagnetic shower interactions in collider ring material in the range of ±200 m from the interaction point.

THPPD042

High Radiation Environment Nuclear Fragment Separator Dipole Magnet

3605

S.A. Kahn
Muons, Inc, Batavia, USA
R.C. Gupta
BNL, Upton, Long Island, New York, USA

Funding: Supported in part by STTR Grant 4746 · 11SC06273
Magnets in the fragment separator region of the Facility for Rare Isotope Beams (FRIB) would be subjected to extremely high radiation and heat loads. Critical elements of FRIB are the dipole magnets which select the desired isotopes. Since conventional NiTi and Nb3Sn superconductors must operate at ~4.5 K, the removal of the high heat load generated in these magnets with these superconductors would be difficult. The coils for these magnets must accommodate the large curvature from the 30° bend that the magnets subtend. High temperature superconductor (HTS) have been shown to be radiation resistant and can operate in the 20-50 K temperature range where heat removal is an order of magnitude more efficient than at 4.5 K. Furthermore these dipole magnets must be removable remotely for servicing because of the extremely high radiation environment. This paper will describe the magnetic and conceptual design of these magnets.

THPPD043

Radiation-tolerant Multipole Correction Coils for FRIB

3608

S.A. Kahn
Muons, Inc, Batavia, USA
R.C. Gupta
BNL, Upton, Long Island, New York, USA

Multipole correction insert coils with significant field strength are required inside the large aperture superconducting quadrupole magnets in the fragment separator section of the Facility for Rare Isotope Beams (FRIB). Correction coils made with copper do not create the required field and conventional low temperature superconductors are not practical in the fragment separator magnets which will operate at 40-50 K. The correction coils should be made of HTS as the main quadrupole coils are. There is a significant advantage to using HTS in these coils as it can withstand the high radiation and heat load that will be present. This paper will describe an innovative design suitable for coils with the complex end geometry of cylindrical coils. We will look at the forces on the corrector coils from the mail quadrupole fields and anticipate possible coil distortions.

THPPD044

Fabrication and Testing of Curved Test Coil for FRIB Fragment Separator Dipole

3611

S.A. Kahn
Muons, Inc, Batavia, USA
J. Escallier, R.C. Gupta, G. Jochen, Y. Shiroyanagi
BNL, Upton, Long Island, New York, USA

Funding: Supported in part by SBIR Grant 4746 · 11SC06273
A critical element of the fragment separator region of the Facility for Rare Isotope Beams (FRIB) is the 30° dipole bend magnet. Because this magnet will be subjected to extremely high radiation and heat loads, operation at 4.5 K would not be possible. High temperature superconductors which have been shown to be radiation resistant and can operated in the 30-50 K temperature range which is more effective for heat removal. An efficient design for this magnet would make use of coils that follow the curvature of the magnet. Winding curved coils with negative curvature are difficult as the coil tends to unwind during the process. As part of an R&D effort for this magnet we are winding a ¼ scale test coil for this magnet with YBCO conductor and are testing it at 77 K. This paper will discuss the winding process and the test results of this study.