T. Fowler

European Organization for Nuclear Research

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Michael Barnes

European Organization for Nuclear Research

J. Borburgh

European Organization for Nuclear Research

F. Roncarolo

European Organization for Nuclear Research

M. Hourican

European Organization for Nuclear Research

V. Ruhlmann-Kleider

CEA Paris-Saclay

Riccardo Torre

Istituto Nazionale di Fisica Nucleare, Sezione di Genova

G. N. Taylor

University of Melbourne

A. K. Morley

European Organization for Nuclear Research

A. Freitas

Deutsches Elektronen-Synchrotron DESY

E. Todesco

European Organization for Nuclear Research

Cooperative Institutions

European Organization for Nuclear Research

540

A. Alikhanyan National Laboratory

151

Centre National de la Recherche Scientifique

133

University of Adelaide

Istituto Nazionale di Fisica Nucleare

Institute of High Energy Physics

Institut National de Physique Nucléaire et de Physique des Particules

Fermi National Accelerator Laboratory

Université Paris-Saclay

University of Antwerp

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LEIR: TOWARDS THE NOMINAL LEAD ION BEAM

M. Chanel V. Baggiolini P. Belochitskii A. Blas J. Borburgh

The Low Energy Ion Ring (LEIR) is a central piece for LHC ion operation at CERN, transforming long Linac3 pulses into high density bunches needed for LHC. The first phase of LEIR commissioning successfully attained its goal of providing the so-called “early ion beam” (one bunch of 2.25 10 8 Lead ions) needed for the first LHC ion runs with reduced luminosity. Studies in view of generating the beam needed for nominal ion operation (2 bunches of 4.5 10 8 ions in LEIR) were carried out in parallel with the setting-up of the early beam in the accelerators further downstream in the LHC injector chain. The main characteristics of the machine using a new state of the art electron cooler are discussed together with the latest results.

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The power supply for a medical synchrotron Beam Chopper System

E. Dallago G. Venchi S. Rossi M. Pullia T. Fowler

In this paper the power supply for the Beam Chopper System of a medical synchrotron is presented. The four, series connected beam chopper magnets, which are placed on the extraction line, are used for blanking the beam both during routine operation and for emergency. To let the beam pass the magnets need to be energized with a current, proportional to the beam energy, whose maximum value is 650 A. Rise and fall time shall be less than 260 mus, while the flat-top can be maintained for an arbitrary long time. The power supply is composed of an high voltage part, which is in charge of the rising and falling current ramp, and of a low voltage part, which is in turn responsible for the current flat top. The paper presents details about the design and experimental results measured on the actual device.

Chopper

10.1109/iecon.2008.4758093

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Septa and Distributor Developments for H- Injection into the Booster from LINAC4

J. Borburgh B. Balhan T. Fowler M. Hourican Wim Weterings

The construction of Linac4 requires the modification of the existing injection system of the CERN PS Booster. A new transfer line will transport 160 MeV H ions to this machine. A system of 5 pulsed magnets (BIDIS) and 3 vertical septa (BISMV) will distribute and inject the Linac pulses into the four-vertically separated Booster rings. Subsequently the beam will be injected horizontally, using a local bump created with bumpers (BS magnets) to bring the injected H beam together with the orbiting proton beam onto the stripper foil. To accommodate the injected H beam, the first of the BS magnets will have to be a septum-like device, deflecting only the orbiting beam. This paper highlights the requirements and technical issues and describes the solutions to be adopted for both the BIDIS and BISMV. The results of initial prototype testing of the BIDIS magnet will also be presented. INTRODUCTION The 160 MeV H beam from the future LINAC4 linear accelerator [1], intended to replace the present 50 MeV LINAC2, needs to be distributed to the 4 superimposed synchrotron rings of the PS Booster (PSB) [2]. In the injection line a system of five pulsed ferrite core magnets (BIDIS), in combination with a fixed field iron magnet (DVT40), will kick time resolved slices of the beam with up to 4.75 mrad deflection sequentially into the appropriate aperture of 3 vertical electromagnetic septa (BISMV) producing the main vertical deflection for beam separation of ~30 mm. The BISMV further deflects the beam vertically into the 4 separate BVT vertical dipole magnet apertures to achieve the required PSB beam-level separation of 360 mm between each ring. So-called head and tail dumps, to which the rising and falling edge of the LINAC4 pulse are deflected, will be positioned just upstream of the BISMV yokes, allowing for maximum beam separation and optimum protection of the BISMV septa. The LINAC4 beams will subsequently be injected horizontally into the PSB by means of an Hchargeexchange injection system using a graphite stripping foil. The local orbit of the PSB circulating beam is horizontally displaced by a set of four pulsed dipole magnets (BS) in order to meet the injected beam. The first BS magnet (BS1) must act as a septum, only deflecting the orbiting beam, with a field-free region for the injected H beam. Table 1: Main BIDIS, BISMV and BS1 magnet parameters

Booster (rocketry)

Transfer line

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An overview of the HIE-ISOLDE Design Study

Nuclear Instruments and Methods in Physics Research Section B Beam Interactions with Materials and Atoms (2013)

R. Catherall Mathieu Augustin C. Babcock R. J. Barlow A. P. Bernardes

Upgrade

Perveance

10.1016/j.nimb.2013.07.030

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DESIGN AND MEASUREMENTS OF A FAST HIGH VOLTAGE PULSE GENERATOR FOR THE MEDAUSTRON LOW ENERGY TRANSFER LINE FAST DEFLECTOR

T. Fowler Michael Barnes Thomas Krämer F. Muller Tobias Stadlbauer

MedAustron, a centre for ion-therapy and research, will comprise an accelerator facility based on a synchrotron for the delivery of protons and light ions for cancer treatment. The Low Energy Beam Transfer line (LEBT) to the synchrotron contains an electrostatic fast deflector (EFE) which, when energized, deviates the continuous beam arriving from the ion source onto a Faraday Cup: the specified voltage is ±3.5 kV. De-energizing the EFE for variable pulse durations from 500 ns up to d.c. allows beam passage for multi-turn injection into the synchrotron. To maintain beam quality in the synchrotron, the EFE pulse generator requires rise and fall times of less than 300 ns between 90 % of peak voltage and a ±1 V level. To achieve this, a pulsed power supply (PKF), with high voltage MOSFET switches connected in a push-pull configuration, will be mounted in close proximity to the deflector itself. A fast, large dynamic range monitoring circuit will verify switching to the ±1 V level and subsequent flat bottom pulse quality. A prototype will be installed in the injector test stand in 2012; this paper presents the design and first measurements of the PKF and its monitoring circuit.

Faraday cup

Transfer line

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FCC-ee: The Lepton Collider

The European Physical Journal Special Topics (2019)

Asmâa Abada M. Abbrescia Shehu AbdusSalam I. M. Abdyukhanov J. Abelleira Fernandez

In response to the 2013 Update of the European Strategy for Particle Physics, the Future Circular Collider (FCC) study was launched, as an international collaboration hosted by CERN. This study covers a highest-luminosity high-energy lepton collider (FCC-ee) and an energy-frontier hadron collider (FCC-hh), which could, successively, be installed in the same 100 km tunnel. The scientific capabilities of the integrated FCC programme would serve the worldwide community throughout the 21st century. The FCC study also investigates an LHC energy upgrade, using FCC-hh technology. This document constitutes the second volume of the FCC Conceptual Design Report, devoted to the electron-positron collider FCC-ee. After summarizing the physics discovery opportunities, it presents the accelerator design, performance reach, a staged operation scenario, the underlying technologies, civil engineering, technical infrastructure, and an implementation plan. FCC-ee can be built with today's technology. Most of the FCC-ee infrastructure could be reused for FCC-hh. Combining concepts from past and present lepton colliders and adding a few novel elements, the FCC-ee design promises outstandingly high luminosity. This will make the FCC-ee a unique precision instrument to study the heaviest known particles (Z, W and H bosons and the top quark), offering great direct and indirect sensitivity to new physics.

10.1140/epjst/e2019-900045-4

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Design of the modulator for the CTF3 tail clipper kicker

Michael Barnes T. Fowler G Ravida Akira Ueda

The goal of the present CLIC Test Facility (CTF3) is to demonstrate the technical feasibility of specific key issues in the CLIC scheme. The extracted beam from the combiner ring (CR), of 35 A in magnitude and 140 ns duration, is sent to the new CLic EXperimental area (CLEX) facility. A tail clipper (TC) is required, in the CR to CLEX transfer line, to allow the duration of the extracted beam pulse to be adjusted. It is proposed to use a stripline kicker for the TC, with each of the deflector plates driven to equal but opposite potential. The TC kick must have a fast rise-time, of not more than 5 ns, in order to minimize uncontrolled beam loss. Several different options are being investigated to meet the demanding specifications for the modulator of the TC. This paper discusses options considered for the fast, high voltage, semiconductor switches and shows results of initial tests on the switches.

Clipper (electronics)

Stripline

Pulse duration

10.1109/pac.2007.4441191

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Citations (6)