The LHC injectors upgrade (LIU) project has been launched at the end of 2010 to prepare the CERN accelerator complex for reliably providing beam with the challenging characteristics required by the high luminosity LHC until at least 2030. Based on the work already started on Linac4, PS Booster, PS and SPS, the LIU project coordinates studies and implementation, and interfaces with the high luminosity LHC (HL-LHC) project which looks after the upgrade of the LHC itself, expected by the end of the present decade. The anticipated beam characteristics are described, as well as the status of the studies and the solutions envisaged for improving the injector performances.

/pdf/plans-for-the-upgrade-of-the-lhc-injectors-13472ewtib.pdf

Plans for the upgrade of the LHC injectors

An accelerator has limited dynamic range: a chain of accelerators is required to reach high energy. A combination of septa and kicker magnets is frequently used to inject and extract beam from each stage. The kicker magnets typically produce rectangular field pulses with fast rise- and/or fall-times, however the field strength is relatively low. To compensate for their relatively low field strength, the kicker magnets are generally combined with electromagnetic septa. The septa provide relatively strong field strength but are either DC or slow pulsed. This paper discusses injection and extraction systems with particular emphasis on the hardware required for the septa.

Injection and extraction magnets: septa

/pdf/injection-and-extraction-magnets-septa-1jssosrunj.pdf

Within the framework of the LHC Injector Upgrade (LIU), the new LINAC4 is currently being commissioned to replace the existing LINAC2 proton source at CERN. After the expected completion at the end of 2016, the LINAC4 will accelerate H − ions to 160 MeV. To measure the transverse emittance of the H − beam, a method based on photo-detachment is proposed. This system will operate using a pulsed laser with light delivered via an optical fibre and subsequently focused onto the H − beam. The laser photons have sufficient energy to detach the outer electron and create H 0 /e − pairs. In a downstream dipole, the created H 0 particles are separated from the unstripped H − ions and their distribution is measured with a dedicated detector. By scanning the focused laser beam across the H − beam, the transverse emittance of the H − beam can be reconstructed. This paper will first discuss the concept, design and simulations of the laser emittance scanner and then present results from a prototype system used during the 12 MeV commissioning of the LINAC4.

/pdf/experimental-results-of-the-laserwire-emittance-scanner-for-3e02grghda.pdf

Experimental results of the laserwire emittance scanner for LINAC4 at CERN

Magnets are at the core of both circular and linear accelerators. The main function of a magnet is to guide the charged particle beam by virtue of the Lorentz force, given by the following expression:where q is the electrical charge of the particle, v its velocity, and B the magnetic field induction. The trajectory of a particle in the field depends hence on the particle velocity and on the space distribution of the field. The simplest case is that of a uniform magnetic field with a single component and velocity v normal to it, in which case the particle trajectory is a circle. A uniform field has thus a pure bending effect on a charged particle, and the magnet that generates it is generally referred to as a dipole.

/pdf/accelerator-engineering-and-technology-accelerator-4wy0mqtrid.pdf

Accelerator Engineering and Technology: Accelerator Technology

/pdf/status-of-the-160meb-h-injection-into-the-cern-psb-4pspi97c8u.pdf

STATUS OF THE 160MeB H-INJECTION INTO THE CERN PSB

The Beam Dumping System for the Large Hadron Collider comprises for each ring a set of horizontally deflecting extraction kicker magnets, vertically deflecting steel septa, dilution kickers and finally, a couple of hundred meters further downstream, an absorber block. A mobile diluter (TCDQ) protects the superconducting quadrupole immediately downstream of the extraction as well as the arc at injection energy and the triplet aperture at top energy from bunches with small impact parameters, in case of a beam dump that is not synchronized with the particle free gap or a spontaneous firing of the extraction kickers. Simulations have shown that an asynchronous dump of a 7 TeV nominal beam into the TCDQ absorber blocks could damage it. This paper describes the proposed changes to this device in order to maintain the protection for the downstream elements while reducing the risk of damaging the TCDQ in case of such a beam loss.

/pdf/upgrade-of-the-lhc-beam-dumping-protection-elements-1iwxc5o1vy.pdf

Upgrade of the LHC Beam Dumping Protection Elements

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.

/pdf/study-of-a-rapid-cycling-synchrotron-to-replace-the-cern-ps-486nhuf7j0.pdf

Study of a rapid cycling synchrotron to replace the cern ps booster

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 475 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

/pdf/septa-and-distributor-developments-for-h-injection-into-the-34tfxtg34w.pdf

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

A linear accelerator (linac) is the first stage of the CERN accelerator complex. The linac defines the beam quality for subsequent stages of acceleration and the reliability has to be high as a fault of the linac shuts down all other machines. The existing linacs at CERN were designed 30 or more years ago: recent upgrades allowed the linacs to reach LHC requirements but also showed that they are at the limit of their brightness and intensity capabilities. A replacement Superconducting Proton Linac (SPL) has been proposed; the initial part of the SPL is termed LINAC4. The LINAC4 injection bump would be made up of a set of four pulsed dipole magnets; the first of these magnets (BS1) must act as a septum with a thin element dividing the high-field region of the circulating beam from the field-free region through which injected H − beam must pass. The initial specifications for BS1 required; a deflection of 66 mrad at 160 MeV, achieved with a peak field of 628 mT and a length of 250 mm: the field fall time was 40 μs with a flattop of at least 100 μs. The ripple of the flattop should be below ±1%. This paper discusses the design of an eddy current septum for BS

/pdf/development-of-an-eddy-current-septum-for-linac4-2y1awuco9b.pdf

Development of an eddy current septum for linac4

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

B.Balhan

Author Tools

Chat about Author