FNAL and CERN are performing an R&D program with the goal of developing a 5.5 m long twin-aperture 11 T Nb 3 Sn dipole suitable for installation in the Large Hadron Collider (LHC). An important part ...of the program is the development and test of a series of short single-aperture and twin-aperture models with a nominal field of 11 T at the LHC nominal current of 11.85 kA and 20% margin. This paper describes design and fabrication features, and test results of a 1 m long single-aperture Nb 3 Sn dipole model tested at FNAL.
FNAL and CERN are carrying out a joint R&D program with the goal of building a 5.5-m-long twin-aperture 11-T Nb 3 Sn dipole prototype that is suitable for installation in the LHC. An important part ...of the program is the development and test of a series of short single-aperture and twin-aperture dipole models with a nominal field of 11 T at the LHC operation current of 11.85 kA and 20% margin. This paper presents the results of magnetic measurements of a 1-m-long single-aperture Nb 3 Sn dipole model fabricated and tested recently at FNAL, including geometrical field harmonics and effects of coil magnetization and iron yoke saturation.
The planned upgrade of the LHC collimation system includes additional collimators in the LHC lattice. The longitudinal space for the collimators could be obtained by replacing some LHC main dipoles ...with shorter but stronger dipoles compatible with the LHC lattice and main systems. A joint development program with the goal of building a 5.5 m long two-in-one aperture <inline-formula> <tex-math notation="TeX">\hbox{Nb}_{3}\hbox{Sn} </tex-math></inline-formula> dipole prototype suitable for installation in the LHC is being conducted by FNAL and CERN magnet groups. As part of the first phase of the program, 1 m long and 2 m long single aperture models are being built and tested, and the collared coils from these magnets will be assembled and tested in two-in-one configuration in both laboratories. In parallel with the short model magnet activities, the work has started on the production line in view of the scale-up to 5.5 m long prototype magnet. The development of the final cryo-assembly comprising two 5.5 m long 11 T dipole cold masses and the warm collimator in the middle, fully compatible with the LHC main systems and the existing machine interfaces, has also started at CERN. This paper summarizes the progress made at CERN and FNAL towards the construction of 5.5 m long 11 T <inline-formula> <tex-math notation="TeX">\hbox{Nb}_{3}\hbox{Sn} </tex-math></inline-formula> dipole prototype and the present status of the activities related to the integration of the 11 T dipole and collimator in the LHC.
Purpose The purpose of this paper is to present a geometric approach to the problem of dimensional reduction. To derive 31 D formulations of 4D field problems in the relativistic theory of ...electromagnetism, as well as 2D formulations of 3D field problems with continuous symmetries. Designmethodologyapproach The framework of differentialform calculus on manifolds is used. The formalism can thus be applied in arbitrary dimension, and with Minkowskian or Euclidean metrics alike. Findings The splitting of operators leads to dimensionally reduced versions of Maxwell's equations and constitutive laws. In the metricincompatible case, the decomposition of the Hodge operator yields additional terms that can be treated like a magnetization and polarization of empty space. With this concept, the authors are able to solve Schiff's paradox without use of coordinates. Practical implications The present formalism can be used to generate concise formulations of complex field problems. The differentialform formulation can be readily translated into the language of discrete fields and operators, and is thus amenable to numerical field calculation. Originalityvalue The approach is an evolution of recent work, striving for a generalization of different approaches, and deliberately avoiding a mix of paradigms.
The planned upgrade of the Large Hadron Collider (LHC) collimation system will include installation of additional collimators in the dispersion suppressor areas. The longitudinal space for the ...collimators could be provided by replacing 15-m-long 8.33 T NbTi LHC main dipoles with shorter 11 T Formula Omitted dipoles compatible with the LHC lattice and main systems. FNAL and CERN have started a joint program with the goal of building a 5.5-m-long twin-aperture Formula Omitted dipole prototype suitable for installation in the LHC. The first step of this program is the development of a 2-m-long single-aperture demonstrator dipole with a nominal field of 11 T at the LHC nominal current of 11.85 kA. This paper summarizes the results of quench protection studies of 11 T dipoles performed using the single-aperture Formula Omitted demonstrator.
The upgrade of the Large Hadron Collider (LHC) collimation system foresees additional collimators in the LHC dispersion suppressor areas. The longitudinal space for the collimators could be provided ...by replacing some NbTi LHC main dipoles with shorter 11 T Formula Omitted dipoles. To demonstrate this possibility, Fermilab and CERN have started a joint program to develop a Formula Omitted dipole prototype suitable for installation in the LHC. The first step of this program is the development of a 2-m-long, 60-mm-bore, single-aperture demonstrator dipole with the nominal field of 11 T at the LHC operational current of 11.85 kA. This paper presents the results of magnetic measurements of the single-aperture Formula Omitted demonstrator dipole including geometrical harmonics, coil magnetization, and iron saturation effects. The experimental data are compared with the magnetic calculations.
The upgrade of the LHC collimation system foresees installation of additional collimators around the LHC ring. The longitudinal space for the collimators could be provided by replacing some 8.33 T ...NbTi LHC main dipoles with shorter 11 T Nb 3 Sn dipoles compatible with the LHC lattice and main systems. To demonstrate this possibility, FNAL and CERN have started a joint program with the goal of building a 5.5 m long twin-aperture dipole prototype suitable for installation in the LHC. The first step of this program is the development of a 2 m long single-aperture demonstrator dipole with a nominal field of 11 T at the LHC nominal current of 11.85 kA and ~ 20% margin. This paper describes the design, construction, and test results of the first single-aperture Nb 3 Sn demonstrator dipole model.
The upgrade of the Large Hadron Collider (LHC) collimation system foresees additional collimators in the LHC dispersion suppressor areas. The longitudinal space for the collimators could be provided ...by replacing some NbTi LHC main dipoles with shorter 11 T Nb 3 Sn dipoles. To demonstrate this possibility, Fermilab and CERN have started a joint program to develop a Nb 3 Sn dipole prototype suitable for installation in the LHC. The first step of this program is the development of a 2-m-long, 60-mm-bore, single-aperture demonstrator dipole with the nominal field of 11 T at the LHC operational current of 11.85 kA. This paper presents the results of magnetic measurements of the single-aperture Nb 3 Sn demonstrator dipole including geometrical harmonics, coil magnetization, and iron saturation effects. The experimental data are compared with the magnetic calculations.
The planned upgrade of the Large Hadron Collider (LHC) collimation system will include installation of additional collimators in the dispersion suppressor areas. The longitudinal space for the ...collimators could be provided by replacing 15-m-long 8.33 T NbTi LHC main dipoles with shorter 11 T Nb 3 Sn dipoles compatible with the LHC lattice and main systems. FNAL and CERN have started a joint program with the goal of building a 5.5-m-long twin-aperture Nb 3 Sn dipole prototype suitable for installation in the LHC. The first step of this program is the development of a 2-m-long single-aperture demonstrator dipole with a nominal field of 11 T at the LHC nominal current of 11.85 kA. This paper summarizes the results of quench protection studies of 11 T dipoles performed using the single-aperture Nb 3 Sn demonstrator.
The LHC collimation upgrade foresees two additional collimators installed in the dispersion suppressor regions of points 2, 3 and 7. To obtain the necessary longitudinal space for the collimators, a ...solution based on an 11 T dipole as replacement of the 8.33 T LHC main dipoles is being considered. CERN and FNAL have started a joint development program to demonstrate the feasibility of rm Nb 3 rm Sn technology for this purpose. The program started with the development and test of a 2-m-long single-aperture demonstrator magnet. The goal of the second phase is the design and construction of a series of 2-m-long twin-aperture demonstrator magnets with a nominal field of 11 T at 11.85 kA current. This paper describes the electromagnetic design and gives a forecast of the field quality including saturation of the iron yoke and persistent-current effects in the rm Nb 3 rm Sn coils. The mechanical design concepts based on separate collared coils, assembled in a vertically split iron yoke are also discussed.
PDF
