2011 Particle Accelerator Conference - List of Authors (Kashikhin, V.)

Paper

Title

Page

Muon Collider Interaction Region and Machine-detector Interface Design

82

N.V. Mokhov, Y. Alexahin, V. Kashikhin, S.I. Striganov, A.V. Zlobin
Fermilab, Batavia, USA

Funding: Work is supported by Fermi Research Alliance, LLC, under contract No. DE-AC02-07CH11359 with the U.S. Department of Energy
One of the key systems of a Muon Collider (MC)- seen as the most exciting options for the energy frontier machine in the post-LHC era - is its interaction region (IR). Designs of its optics, magnets and machine-detector interface are strongly interlaced and iterative. As a result of recent comprehensive studies, consistent solutions for the 1.5 TeV c.o.m. MC IR have been found and are described here. To provide the required momentum acceptance, dynamic aperture and chromaticity, innovative approach was used for the IR optics. Conceptual designs of large-aperture high-field dipole and high-gradient quadrupole magnets based on Nb₃Sn superconductor were developed and analyzed in terms of the operation margin, field quality, mechanics, coil cooling and quench protection. Shadow masks in the interconnect regions and liners inside the magnets are used to mitigate unprecedented dynamic heat deposition due to muon decays (~1 kW/m). It is shown that an appropriately designed machine-detector interface with sophisticated shielding in the detector has a potential to substantially suppress the background rates in the MC detector.

Slides MOODN6 [1.233 MB]

WEOCS2

Development of Nb3Sn 11 T Single Aperture Demonstrator Dipole for LHC Upgrades

1460

A.V. Zlobin, N. Andreev, G. Apollinari, E.Z. Barzi, V. Kashikhin, A. Nobrega, I. Novitski
Fermilab, Batavia, USA
B. Auchmann, M. Karppinen, L. Rossi
CERN, Geneva, Switzerland

Funding: Work is supported by Fermi Research Alliance, LLC, under contract No. DE-AC02-07CH11359 with the U.S. Department of Energy
The LHC collimation upgrade foresees additional collimators installed in dispersion suppressor regions. To obtain the necessary space for the collimators, a solution based on the substitution of LHC main dipoles for stronger dipoles is being considered. CERN and FNAL have started a joint program to demonstrate the feasibility of Nb3Sn technology for this purpose. The goal of the first phase is the design and construction of a 2-m long single-aperture demonstrator magnet with a nominal field of 11 T at 11.85 kA with 20% margin. This paper describes the magnetic and mechanical design of the demonstrator magnet and summarizes its design parameters.

Slides WEOCS2 [2.523 MB]

THP048

Radiation and Thermal Analysis of Production Solenoid for Mu2e Experimental Setup

2208

V.S. Pronskikh, V. Kashikhin, N.V. Mokhov
Fermilab, Batavia, USA

The Muon-to-Electron (Mu2e) experiment at Fermilab, will seek the evidence of direct muon to electron conversion that cannot be explained by the Standard Model. An 8 GeV 25 kW proton beam will be directed onto a gold target inside a large-bore superconducting Production Solenoid (PS) with the peak field on the axis of ~5T. The negative muons resulting from the pion decay will be captured in the PS aperture and directed by an S-shaped Transport Solenoid towards the stopping target inside the Detector Solenoid. In order for the superconducting magnets to operate reliably and with a sufficient safety margin, the peak neutron flux entering the coils must be reduced by 3 orders of magnitude that is achieved by means of a sophisticated absorber placed in the magnet aperture. The proposed absorber, consisting of W and Cu parts, is optimized for the performance and cost. Results of MARS15 of energy deposition and radiation analysis are reported. The results of the PS magnet thermal analysis, coordinated with the coil cooling scheme, are reported as well for the selected absorber design.

THP085

Radiation Effects in a Muon Collider Ring and Dipole Magnet Protection

2294

N.V. Mokhov, V. Kashikhin, I. Novitski, A.V. Zlobin
Fermilab, Batavia, USA

Funding: Work is supported by Fermi Research Alliance, LLC, under contract No. DE-AC02-07CH11359 with the U.S. Department of Energy.
Requirements and operating conditions for a Muon Collider Ring (MCR) pose significant challenges to superconducting magnets. The dipole magnets should provide a high magnetic field to reduce the ring circumference and thus maximize the number of muon collisions during their lifetime. One third of the beam energy is continuously deposited along the lattice by the decay electrons at the rate of 0.5 kW/m for a 1.5-TeV c.o.m. MCR. Unlike dipoles in proton machines, the MCR dipoles should allow this dynamic heat load to escape the magnet helium volume in horizontal plane predominantly towards the ring center. Two alternative designs, one based on the open mid-plane approach with block type coils and absorber outside the coils, and another based on the traditional large-aperture cos-theta approach with a shifted beam pipe and absorber inside the coil aperture were developed for the MCR designed for a luminosity of 10³⁴ cm^-2s⁻¹. This paper presents the analysis and comparison of radiation effects in MCR based on the two dipole magnets. Tungsten masks in the interconnect regions are used in both cases to mitigate the unprecedented dynamic heat deposition and radiation in the magnet coils.

TUP174

Warm Magnetic Field Measurements of LARP HQ Magnet

1154

X. Wang, S. Caspi, D.W. Cheng, D.R. Dietderich, H. Felice, P. Ferracin, R.R. Hafalia, J.M. Joseph, J. Lizarazo, M. Martchevskii, C. Nash, G.L. Sabbi, C. Vu
LBNL, Berkeley, California, USA
G. Ambrosio, R. Bossert, G. Chlachidze, J. DiMarco, V. Kashikhin
Fermilab, Batavia, USA
J. Schmalzle, P. Wanderer
BNL, Upton, Long Island, New York, USA

The US-LHC Accelerator Research Program is develop- ing and testing a high-gradient quadrupole (HQ) magnet, aiming at demonstrating the feasibility of Nb3Sn technologies for the LHC luminosity upgrade. The 1 m long HQ magnet has a 120 mm bore with a conductor-limited gradient of 219 T/m at 1.9 K and a peak field of 15 T. HQ includes accelerator features such as alignment and field quality. Here we present the magnetic measurement results obtained at LBNL with a constant current of 30 A. A 100 mm long circuit-board rotating coil developed by FNAL was used and the induced voltage and flux increment were acquired. The measured b6 ranges from 0.3 to 0.5 units in the magnet straight section at a reference radius of 21.55 mm. The data reduced from the numerical integration of the raw voltage agree with those from the fast digital integrators.

Paper	Title	Page
MOODN6	Muon Collider Interaction Region and Machine-detector Interface Design	82
	N.V. Mokhov, Y. Alexahin, V. Kashikhin, S.I. Striganov, A.V. Zlobin Fermilab, Batavia, USA
	Funding: Work is supported by Fermi Research Alliance, LLC, under contract No. DE-AC02-07CH11359 with the U.S. Department of Energy One of the key systems of a Muon Collider (MC)- seen as the most exciting options for the energy frontier machine in the post-LHC era - is its interaction region (IR). Designs of its optics, magnets and machine-detector interface are strongly interlaced and iterative. As a result of recent comprehensive studies, consistent solutions for the 1.5 TeV c.o.m. MC IR have been found and are described here. To provide the required momentum acceptance, dynamic aperture and chromaticity, innovative approach was used for the IR optics. Conceptual designs of large-aperture high-field dipole and high-gradient quadrupole magnets based on Nb₃Sn superconductor were developed and analyzed in terms of the operation margin, field quality, mechanics, coil cooling and quench protection. Shadow masks in the interconnect regions and liners inside the magnets are used to mitigate unprecedented dynamic heat deposition due to muon decays (~1 kW/m). It is shown that an appropriately designed machine-detector interface with sophisticated shielding in the detector has a potential to substantially suppress the background rates in the MC detector.
	Slides MOODN6 [1.233 MB]

WEOCS2	Development of Nb3Sn 11 T Single Aperture Demonstrator Dipole for LHC Upgrades	1460
	A.V. Zlobin, N. Andreev, G. Apollinari, E.Z. Barzi, V. Kashikhin, A. Nobrega, I. Novitski Fermilab, Batavia, USA B. Auchmann, M. Karppinen, L. Rossi CERN, Geneva, Switzerland
	Funding: Work is supported by Fermi Research Alliance, LLC, under contract No. DE-AC02-07CH11359 with the U.S. Department of Energy The LHC collimation upgrade foresees additional collimators installed in dispersion suppressor regions. To obtain the necessary space for the collimators, a solution based on the substitution of LHC main dipoles for stronger dipoles is being considered. CERN and FNAL have started a joint program to demonstrate the feasibility of Nb3Sn technology for this purpose. The goal of the first phase is the design and construction of a 2-m long single-aperture demonstrator magnet with a nominal field of 11 T at 11.85 kA with 20% margin. This paper describes the magnetic and mechanical design of the demonstrator magnet and summarizes its design parameters.
	Slides WEOCS2 [2.523 MB]

THP048	Radiation and Thermal Analysis of Production Solenoid for Mu2e Experimental Setup	2208
	V.S. Pronskikh, V. Kashikhin, N.V. Mokhov Fermilab, Batavia, USA
	The Muon-to-Electron (Mu2e) experiment at Fermilab, will seek the evidence of direct muon to electron conversion that cannot be explained by the Standard Model. An 8 GeV 25 kW proton beam will be directed onto a gold target inside a large-bore superconducting Production Solenoid (PS) with the peak field on the axis of ~5T. The negative muons resulting from the pion decay will be captured in the PS aperture and directed by an S-shaped Transport Solenoid towards the stopping target inside the Detector Solenoid. In order for the superconducting magnets to operate reliably and with a sufficient safety margin, the peak neutron flux entering the coils must be reduced by 3 orders of magnitude that is achieved by means of a sophisticated absorber placed in the magnet aperture. The proposed absorber, consisting of W and Cu parts, is optimized for the performance and cost. Results of MARS15 of energy deposition and radiation analysis are reported. The results of the PS magnet thermal analysis, coordinated with the coil cooling scheme, are reported as well for the selected absorber design.

THP085	Radiation Effects in a Muon Collider Ring and Dipole Magnet Protection	2294
	N.V. Mokhov, V. Kashikhin, I. Novitski, A.V. Zlobin Fermilab, Batavia, USA
	Funding: Work is supported by Fermi Research Alliance, LLC, under contract No. DE-AC02-07CH11359 with the U.S. Department of Energy. Requirements and operating conditions for a Muon Collider Ring (MCR) pose significant challenges to superconducting magnets. The dipole magnets should provide a high magnetic field to reduce the ring circumference and thus maximize the number of muon collisions during their lifetime. One third of the beam energy is continuously deposited along the lattice by the decay electrons at the rate of 0.5 kW/m for a 1.5-TeV c.o.m. MCR. Unlike dipoles in proton machines, the MCR dipoles should allow this dynamic heat load to escape the magnet helium volume in horizontal plane predominantly towards the ring center. Two alternative designs, one based on the open mid-plane approach with block type coils and absorber outside the coils, and another based on the traditional large-aperture cos-theta approach with a shifted beam pipe and absorber inside the coil aperture were developed for the MCR designed for a luminosity of 10³⁴ cm^-2s⁻¹. This paper presents the analysis and comparison of radiation effects in MCR based on the two dipole magnets. Tungsten masks in the interconnect regions are used in both cases to mitigate the unprecedented dynamic heat deposition and radiation in the magnet coils.

TUP174	Warm Magnetic Field Measurements of LARP HQ Magnet	1154
	X. Wang, S. Caspi, D.W. Cheng, D.R. Dietderich, H. Felice, P. Ferracin, R.R. Hafalia, J.M. Joseph, J. Lizarazo, M. Martchevskii, C. Nash, G.L. Sabbi, C. Vu LBNL, Berkeley, California, USA G. Ambrosio, R. Bossert, G. Chlachidze, J. DiMarco, V. Kashikhin Fermilab, Batavia, USA J. Schmalzle, P. Wanderer BNL, Upton, Long Island, New York, USA
	The US-LHC Accelerator Research Program is develop- ing and testing a high-gradient quadrupole (HQ) magnet, aiming at demonstrating the feasibility of Nb3Sn technologies for the LHC luminosity upgrade. The 1 m long HQ magnet has a 120 mm bore with a conductor-limited gradient of 219 T/m at 1.9 K and a peak field of 15 T. HQ includes accelerator features such as alignment and field quality. Here we present the magnetic measurement results obtained at LBNL with a constant current of 30 A. A 100 mm long circuit-board rotating coil developed by FNAL was used and the induced voltage and flux increment were acquired. The measured b6 ranges from 0.3 to 0.5 units in the magnet straight section at a reference radius of 21.55 mm. The data reduced from the numerical integration of the raw voltage agree with those from the fast digital integrators.