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This paper collects the machine development (MD) activities for the beam transfer studies in 2016 concerning the PSB extraction and the PSB-to-PS transfer. Many topics are covered: from the 160 MeV extraction from the PSB, useful for the future commissioning activities after the connection with Linac4, to new methodologies for measuring the magnetic waveforms of kickers and dispersion reduction schemes at PS injection, which are of great interest for the LHC Injectors Upgrade (LIU) [1] project., CERN Proceedings, Vol 2 (2017): Proceedings of the Injector MD Days 2017

The use of regional analgesia techniques for postoperative analgesia in spine surgery is less frequently used in comparison with conventional oral and parenteral treatment. This may be explained by the fact that surgery is mostly performed under general anesthesia. Although objections of the surgeon are comprehensible, there is a growing number of studies using regional techniques for the treatment of pain after this surgery. When postoperative analgesia is the focus then regional techniques can be initiated at any time-point of the procedure while all ages and types of surgery, even extensive scoliosis fusion may benefit from it. The present overview will focus on the feasibility of (loco)regional techniques to be used for postoperative analgesia, medications used alone or in combination, as a single bolus or through persistent catheters and with special attention to pain relief following scoliosis repair. In general neuraxial techniques offer lower pain scores and/or less need for opioid rescue in comparison with systemic conventional analgesia although much less benefit may be noticed in patients operated for spinal fusion than for disc surgery, laminectomy and adolescent scoliosis correction. The actual literature provides little evidence with respect to the best timing of initiation, the best route nor the best dose in relationship to the type of surgery. Besides neuraxial techniques several alternatives have found their way in this type of intervention. As all techniques described offered variable success rates, future research is mandatory to determine their superiority over general anesthesia and conventional pain therapy modalities.

In the context of the LHC High Luminosity Upgrade project a performance upgrade for heavy ions is envisaged. One of the performance limitations is the rise time of the present SPS injection kicker system MKP. A reduction of the rise time for lead ions was studied in line with a modification of the whole injection system. This paper briefly describes the different rise time options studied for an initially proposed dedicated ion kicker system MKP-I, focuses however on a cost effective alternative using the presently installed 12 MKPS magnets connected to a new fast pulse forming line. As only 12 out of the 16 injection kicker magnets would be fast enough to be used in an upgraded system, additional deflection has to be provided by the septa. The beam optics for that variant is highlighted and first requirements for the septum elements are stipulated. The paper concludes with a failure analysis of the proposed scheme.

This Report gives a full description of the ELENA Ring to be built within the circumference of the Antiproton Decelarator (AD) Ring, in Building 193 at CERN. The ELENA ring will further decelerate the antiprotons coming from the AD at the momentum of 100 MeV/c down to 13.7 MeV/c, which corresponds to the kinetic energy of 100 keV before extracting to the physics experiments in the same building. The history of such an extra low energy antiproton ring at CERN goes a long way back, and even to the Decelerator’s previous incarnation, the Low Energy Antiproton Ring (LEAR), which came into operation in 1983. Already at that time, there were physics’ requests to further decelerate the antiprotons expected from LEAR by proposals for ELENA. Appendix I illustrates the cover pages of two such CERN documents from 1982.

The CERN PS Booster extraction energy will be upgraded from 1.4 to 2.0 GeV to alleviate the direct space charge tune shift in the PS. The focussing structure of the transfer line will be modified in order to better match the optics between the PSB and the PS. The optics of the PS at injection and, with it, of the transfer line can be adapted to reduce the continuous losses from the already injected and circulating beam bumped towards the septum. Experimental results of the optics optimisation and probing the injection kicker flat top are shown. Modifications of the recombination septa and the main horizontal bending magnet in the measurement line are presented.

In 2011 the ELENA decelerator was approved as a CERN project. Initially one extraction was foreseen, which should use a kicker and a magnetic septum which can be recuperated from an earlier installation. Since then a second extraction has been approved and a new solution was studied using only electric fields to extract the beam. This will be achieved by fast pulsing a separator, allowing single-bunch but also a full single-turn extraction from ELENA towards the experiments. The extraction and transfer requirements of ELENA are described, followed by the principal differences between the magnetic and electric field concepts. The design of electrostatic focussing and bending devices for the transfer lines will be presented. Finally the field quality which can be achieved with the separator and the concept of its power supply will be discussed.

The LHC High Luminosity upgrade project includes a performance upgrade for heavy ions. One of the present performance limitations is the rise time of the SPS injection kicker system, which imposes a spacing of at least 220 ns between injected bunch trains at the operational rigidity. A reduction of this rise time to 50 ns for lead ions is requested as part of the suite of measures needed to increase the present design performance by a factor three. A new injection system based on a fast pulsed septum and a fast kicker has been proposed to fulfil this rise time requirement, and to meet all the constraints associated with the existing high intensity proton injection in the same region. This paper describes the concept and the required equipment parameters, and explores the implications of such a system for SPS operation.

Conceptual studies have been made for a 2 GeV RCS at CERN as a possible replacement of the four-ring PS Booster. The lattice design has to accommodate suitable straight sections for a 160 MeV H- charge exchange injection system, and for a 2 GeV fast extraction system. The design constraints for the injection and extraction systems are described, together with the proposed concepts and potential equipment limitations.

CERN’s proton injector chain is undergoing a massive consolidation and upgrade program in order to deliver beams meeting the needs of the LHC Luminosity Upgrade. As an alternative to the upgrade of the existing Proton Synchrotron Booster (PSB), the construction of a Rapid Cycling Synchrotron (RCS) has been studied. This machine would replace the PSB and deliver beams to the LHC as well as to CERN’s rich fixed-target physics program. This paper summarizes the outcome of the feasibility study along with a tentative RCS design.

To reduce the beam losses when preparing high intensity proton beam for the CERN Neutrino to Gran Sasso (CNGS) facility, a new Multi-Turn extraction (MTE) scheme has been implemented in the PS, to replace the present Continuous Transfer (CT) to the SPS. Industrial off-the-shelf components have been used for the low-level part of the MTE kicker control system. National Instruments PXI systems are used to control the high voltage pulse generators and a SIEMENS programmable logic controller (PLC) handles the centralised oil cooling and gas insulation sub-systems

The implementation of the new Multi-Turn Extraction (MTE) at the CERN Proton Synchrotron required major hardware changes for the nearly 50-year old accelerator. The installation of new Pulse Forming Networks (PFN) and refurbished kicker magnets for the extraction, new sextupole and octupole magnets, new power converters, together with an in-depth review of the machine aperture leading to the design of new vacuum chambers was required. As a result, a heavy programme of interventions had to be scheduled during the winter shut-down 2007-8. The newly installed hardware and its commissioning is presented and discussed in details.

The H- beam from the proposed LINAC4 will be injected into the four existing rings of the PS Booster at 160 MeV. A substantial upgrade of the injection region is required, including the modification of the beam distribution system and the construction of a new H- injection system. This paper discusses beam dynamics and hardware requirements and presents the results of optimisation studies of the injection process for different beam characteristics and scenarios. The resulting conceptual design of the injection region is presented, together with the main hardware modifications and performance specifications.

Since 2001 considerable effort has been devoted to the study of a possible replacement of the continuous-transfer extraction mode from the PS to the SPS. Such an approach, called Multi-Turn Extraction (MTE), is based on capture of the beam inside stable islands of transverse phase space, generated by sextupoles and octupoles, thanks to a properly chosen tune variation. Both numerical simulations and measurements with beam were performed to understand the properties of this new extraction mode. The experimental study was completed at the end of 2004 and by the end of 2005 a scheme to implement this novel approach in the PS machine was defined and its performance assessed. This design report presents the outcome of the studies undertaken both in terms of technical issues as well as of resources necessary to implement the proposed scheme.

A sizeable part of the LHC physics programme foresees lead-lead collisions with a design luminosity of 1027 cm-2 s-1. This will be achieved after an upgrade of the ion injector chain comprising Linac3, LEIR, PS and SPS machines [1,2]. Each LHC ring will be filled in 10 min by almost 600 bunches, each of 7×107 lead ions. Central to the scheme is the Low Energy Ion Ring (LEIR) [3,4], which transforms long pulses from Linac3 into high-brilliance bunches by means of multi-turn injection, electron cooling and accumulation. Major limitations along the chain, including space charge, intrabeam scattering, vacuum issues and emittance preservation are highlighted. The conversion from LEAR (Low Energy Antiproton Ring) to LEIR involves new magnets and power converters, high-current electron cooling, broadband RF cavities, and a UHV vacuum system with getter (NEG) coatings to achieve a few 10-12 mbar. Major hardware changes in Linac3 and the PS are also covered. An early ion scheme with fewer bunches (but each at nominal intensity) reduces the work required for early LHC ion operation in spring 2008.

Since the year 2001 considerable efforts were devoted to the study of a possible replacement of the Continuous Transfer (CT) extraction mode from the PS to the SPS. Such an approach is based on the use of stable islands of phase space, generated by sextupoles and octupoles, to capture the beam inside, thanks to a properly chosen tune variation. Both numerical simulations and measurements with beam were performed to understand the properties of this new extraction mode. Recently, a Study Group was set-up with the mandate of studying this novel extraction in view of using it as a replacement for the CT, as well as technical issues related with this approach. The results of the analysis carried out so far, and the conclusions of the Study Group are presented and discussed in this report.

In the framework of a collaboration agreement with the TERA Foundation, CERN provided the design, drawings and engineering specifications for two kickers, one chopper and three bumper magnets as well as three magnetic and two electrostatic septa, power supplies for the electrostatic septa, kickers and bumpers including control electronics for the PIMMS/TERA proton and carbon ion medical synchrotron. The first application will be in the Italian National Centre for Hadrontherapy, to be constructed in Pavia. The main features of the devices are described along with the strategic design choices, directed by the demand for very high reliability and minimum maintenance.

A synchrotron machine, capable to accelerate either light ions or protons, will be the basic instrument of the CNA (Centro Nazionale di Adroterapia), the medical center dedicated to the cancer therapy, that will be built in Italy in the near future. The machine complex consists of one proton-carbon-ion linac that will accelerate the particles till the energy of 7 MeV/u. An injection line will transport them to the synchrotron ring where the injected particles will be accelerated and extracted with an energy ranging from 60 to 250 MeV for protons and from 120 to 400 MeV/u for carbon ions. Fig. 1 shows a preliminary schematic picture of the CNA medical center.

A synchrotron machine, capable to accelerate either light ions or protons, will be the basic instrument of the CNA (Centro Nazionale di Adroterapia), the medical centre dedicated to the cancer therapy, that will be built in Italy in the near future. The machine complex consists of one proton-carbon-ion linac that will accelerate the particles up to an energy of 7 MeV/u. An injection line will transport them to the synchrotron ring where the injected particles will be accelerated and extracted with an energy ranging from 60 to 250 MeV for protons and from 120 to 400 MeV/u for carbon ions. Fig. 1 shows a preliminary schematic picture of the CNA medical centre.

A synchrotron machine, capable to accelerate either light ions or protons, will be the basic instrument of the CNA (Centro Nazionale di Adroterapia), the medical centre dedicated to the cancer therapy, that will be built in Italy in the near future. The machine complex consists of one proton-carbon-ion linac that will accelerate the particles up to an energy of 7 MeV/u. An injection line will transport them to the synchrotron ring where the injected particles will be accelerated and extracted with an energy ranging from 60 to 250 MeV for protons and from 120 to 400 MeV/u for carbon ions. Fig. 1 shows a preliminary schematic picture of the CNA medical centre.

A synchrotron machine, capable to accelerate either light ions or protons, will be the basic instrument of the CNA (Centro Nazionale di Adroterapia), the medical centre dedicated to the cancer therapy, that will be built in Italy in the near future. The machine complex consists of one proton-carbon-ion linac that will accelerate the particles up to an energy of 7 MeV/u. An injection line will transport them to the synchrotron ring where the injected particles will be accelerated and extracted with an energy ranging from 60 to 250 MeV for protons and from 120 to 400 MeV/u for carbon ions. Fig. 1 shows a preliminary schematic picture of the CNA medical centre.

The final design review for the 5 different Septa and 5 different Bumper, Chopper and Kicker systems is given. The specifications for all items have been finalized and the parameters have been fixed and these are shown in two tables. The present status of each special magnet is reported on.

Afin de tester la faisabilité de la nouvelle extraction multi-tours en cours d'étude au PS, les BFA doivent être pulsés à des niveaux de tensions différents de ceux utilisés pour le CT actuel. Le but du MD était de déterminer s'il est possible d'utiliser les BFA pour effectuer les deux types d'éjection dans un même supercycle.

The status of the design review for the 5 different Septa and 5 different Bumper, Chopper and Kicker systems is given. The specifications for all items have been reviewed and the parameters have been fixed and these are shown in five tables. In some cases the operational requirements are not completely fixed and optional pulsed power supplies are proposed to cope with most situations. The present status of each special magnet is reported on.