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The High Luminosity LHC (HL-LHC) project is aimed at studying and implementing the necessary changes in the LHC to increase its luminosity by a factor five. Among the magnets that will be upgraded are the 16 superconducting low-β quadrupoles placed around the two high luminosity interaction regions (ATLAS and CMS experiments). In the current baseline scenario, these quadrupole magnets will have to generate a gradient of 140 T/m in a coil aperture of 150 mm. The resulting conductor peak field of more than 12 T will require the use of Nb$_{3}$Sn superconducting coils. We present in this paper the HL-LHC low-β quadrupole design, based on the experience gathered by the US LARP program, and, in particular, we describe the support structure components to pre-load the coils, withstand the electro-magnetic forces, provide alignment and LHe containment, and integrate the cold mass in the LHC IRs.

In preparation for the high luminosity upgrade of the Large Hadron Collider (LHC), the LHC Accelerator Research Program (LARP) is developing a new generation of large aperture high-field quadrupoles based on Nb$_{3}$Sn technology. One meter long and 120 mm diameter HQ quadrupoles are currently produced as a step toward the eventual aperture of 150 mm. Tests of the first series of HQ coils revealed the necessity for further optimization of the coil design and fabrication process. A new model (HQ02) has been fabricated with several design modifications, including a reduction of the cable size and an improved insulation scheme. Coils in this magnet are made of a cored cable using 0.778 mm diameter Nb$_{3}$Sn strands of RRP 108/127 sub-element design. The HQ02 magnet has been fabricated at LBNL and BNL, and then tested at Fermilab. This paper summarizes the performance of HQ02 at 4.5 K and 1.9 K temperatures. In preparation for the high luminosity upgrade of the Large Hadron Collider (LHC), the LHC Accelerator Research Program (LARP) is developing a new generation of large aperture high-field quadrupoles based on Nb_3Sn technology. One meter long and 120 mm diameter HQ quadrupoles are currently produced as a step toward the eventual aperture of 150 mm. Tests of the first series of HQ coils revealed the necessity for further optimization of the coil design and fabrication process. A new model (HQ02) has been fabricated with several design modifications, including a reduction of the cable size and an improved insulation scheme. Coils in this magnet are made of a cored cable using 0.778 mm diameter Nb_3Sn strands of RRP 108/127 subelement design. The HQ02 magnet has been fabricated at LBNL and BNL, and then tested at Fermilab. This paper summarizes the performance of HQ02 at 4.5 K and 1.9 K temperatures.

Beyond HL-LHC, CERN has a number of physics options that offer potential and challenges. This contribution dwells on the long-term projects HE-LHC and LHeC to put the magnet R&D at CERN (resistive and superconducting, slow and fast) in a long-term perspective. In particular synergies and parallel roadmaps will be highlighted. We will show how the on-going development (2012-2015) on low-field, high-field, and low-loss magnets can be used towards longer term objectives.

Linac4 is a new H- linear accelerator at CERN replacing Linac2 as injector to the PS Booster. Almost 100 electro-magnets of different types are needed for the Linac4 project. Following a detailed analysis of the requirements and constraints, several magnet designs have been studied and are well advanced. This paper presents the design considerations, main parameters and characteristics of the new Linac4 magnets and summarizes the present status.

The phase I LHC upgrade foresees the installation of a new final focusing for the high luminosity experiences in order to be able to focus the beams in the interaction points to b*~ 0.25 cm. Key element of this upgrade is a large bore (120 mm) superconducting quadrupole. This article proposes a magnet design that will make use of the LHC main dipole superconducting cable. Due to the schedule constraints and to the budget restrictions, it is mandatory to integrate in the design the maximum number of features successfully used during the LHC construction. This paper presents this design option and the rationales behind the several technical choices.

One option in the scenario of upgrades of the LHC accelerator complex is to replace the existing CERN Proton Synchrotron (PS) by a new and larger synchrotron (PS2). Since the launch of the PS2 study project in 2003, specifications on the magnet lattice have continuously evolved. We propose here, according to the latest lattice configuration, a conceptual design for the normal-conducting and iron-dominated PS2 main dipole. The method we used to search for the optimal design is also presented.

One option in the scenario of upgrades of the LHC accelerator complex is to replace the existing CERN Proton Synchrotron (PS) by a new and larger synchrotron (PS2). Since the launch of the PS2 study project in 2003, specifications on the magnet lattice have continuously evolved. We propose here, according to the latest lattice configuration, a conceptual design for the four types of normal-conducting and iron-dominated main quadrupoles for the PS2. Three of them have the same cross-section but differ in magnetic length. The method we used to search for optimal designs is also presented.

The phase I of the LHC upgrade aims at increasing the luminosity by a factor 2-3 with respect to the nominal luminosity of 10**34 cm**-2s**-1. Part of this increase is obtained through a reduction of Beta* from 55 to 25-30 cm. This requires the replacement of the present quadrupole triplets of 70 mm aperture around the Atlas ad CMS interaction regions with a new set of Nb-Ti quadrupoles with 120 mm aperture. In this paper we present a proposal for the electromagnetic design of the coil cross-section and of the non-connection side of the coil ends. We also present an estimate of the field quality components, using the usual split among systematic, uncertainty associated to the systematic and random part.

While the Large Hadron Collider (LHC) at CERN is starting operation with beam, aiming to achieve nominal performance in the shortest term, the upgrade of the LHC interaction regions is actively pursued in order to enhance the physics reach of the machine. Its first phase, with the target of increasing the LHC luminosity to 2-3 1034cm-2s-1, relies on the mature Nb-Ti superconducting magnet technology and is intended to maximize the use of the existing infrastructure. The impact of the increased power of the collision debris has been investigated through detailed energy deposition studies, considering the new aperture requirements for the low-ß quadrupoles and a number of other elements in the insertions. Effective solutions in terms of shielding options and design/layout optimization have been envisaged and the crucial factors have been pointed out.

In the framework of the studies for the upgrade of the insertions of the CERN Large Hadron Collider, four optical layouts were proposed with the aim of reducing the beta-function at the collision point down to 25 cm. The different candidate layouts are presented. Results from the studies performed on mechanical and dynamic aperture are summarized, together with the evaluation of beam-beam effects. Particular emphasis is given to the comparison of the optics performance, which led to retain the most promising layouts for further development.

To be able to make a global parametric analysis and to have some basic understanding of the influence of critical parameters, scaling laws may be of help. For the design of the LHC insertion regions triplets, among the critical parameters the energy deposited in the superconducting triplet plays a fundamental role in avoiding magnet quench, too heavy load on the cryogenic system, and degradation of the materials due to radiation. The influence on energy deposition of the lay-out key parameters, such as the magnet apertures, the magnet lengths and positions, has been studied for beta* = 0.25 m

The stored energy in superconducting magnets is one of the main ingredients needed for the quench calculation and for designing quench protections. Here we propose an analytical formula based on the Fourier transformation of the current density flowing within the winding to determine the magnetic energy stored in superconducting quadrupoles made of sector coils. Two corrective coefficients allowing to estimate the energy enhancement produced either by current grading or by the presence of an unsaturated iron yoke are respectively derived from a numerical and an analytical study. This approach is applied to a set of real quadrupoles to test the validity limits of the scaling law, which are shown to be of ~10%.

The Beta-Beam project is a concept of large scale facility that aims at providing pure electronic neutrino and antrineutrino beams for the measurement of nu_e --> nu_µ oscillations, offering unprecedented sensitivity for detection of the Theta_13 mixing angle and CP violating phase. In the scenario presented in different publications [1-3], a Beta-Beam facility could be advantageously placed at CERN making use of the PS and SPS for accelerating the beta-decaying, neutrino-emitting beams to a Lorentz gamma of 100. Intense beams of 6He and 18Ne would be produced using the so-called “isotope-separation on line” ISOL method in a facility of the scale of EURISOL. The synergy between the two projects was pointed out in [4]. The task 12 of the EURISOL design study aimed at producing a conceptual design report for the accelerator chain of a EURISOL/CERN-baseline Beta-Beam facility. This document summarizes the achievements made during the time of the study and constitutes the final conceptual report of the beta-beam facility. References [1] B. Autin, M. Benedikt, M. Grieser, S. Hancock, H. Haseroth, A. Jansson, U. Köster, M. Lindroos, S. Russenschuck and F. Wenander, \"The acceleration and storage of radioactive ions for a neutrino factory\", CERN/PS 2002-078 (OP), Nufact Note 121, J. Phys. G 29 (2003) 1785-1796 and long internal CERN version, PS/OP/Note 2002-181. [2] M.Mezzetto, \"Physics reach of the beta-beam\", J. Phys. G: Nucl. Part. Phys. 29 (2003) 1771–1776 [3] J. Bouchez, M. Lindroos and M. Mezzetto, 5th International Workshop on Neutrino Factories and Superbeams; NuFact 03. AIP Conference Proceedings, Volume 721, pp. 37-47 (2004). [4] Letter of Intent: FP6 Design Study for a beta-beam facility , September, 2003

Lindroos, M. Magistris, A. Mueller, J. Payet, P. Puppel, P. Spiller, A. Tkatchenko, S. Trovati, V. Vlachoudis