Review of LHC and Injector Upgrade Plans Workshop (RLIUP)

Europe/Zurich
Centre de Convention, Archamps

Centre de Convention, Archamps

Domaine de Chosal Archamps Technopole 74160 Archamps
Description

*** Invitation Only***
 
The workshop will focus on:

Review of the parameters of the LIU and HL-LHC projects following the experience and changes in the beam parameters experienced in the past two years

Produce a staged plan(beam parameters, technical work, all machines) of how we proceed from the performance at the end of 2012 to the required performance for the HL-LHC. In order to do this we need to know at what level of integrated luminosity will necessitate replacement of the inner detectors and the insertions. Also to see the importance of 3000fb-1 and what level of minimum integrated luminosity would be tolerated.
 
  • Chairman :                                        Steve Myers
  • Co-Chairman :                                  Frédérick Bordry
  • Deputy Chairman :                          Mike Lamont
  • Scientific Secretary:                        Frank Zimmermann
  • Deputy Scientific Secretary:          Brennan Goddard
  • Technical Support                           Pierre Charrue

Editor of proceedings: Frank Zimmermann and Brennan Goddard


***Deadline for registration: Friday 27 September 2013***

Session Chairpersons
 
Session 1: Austin Ball / Mike Lamont                          
Session 2: Gianluigi Arduini / Steve Hancock
Session 3: Malika Meddahi / Lucio Rossi
Session 4: Brennan Goddard / Roland Garoby
Session 5: Oliver Brüning/Massi Ferro-Luzzi
Session 6: Steve Myers / Frank Zimmermann
 
Participants
  • Alessandra Lombardi
  • Amalia Ballarino
  • Austin Ball
  • Benedetto Gorini
  • Beniamino Di Girolamo
  • Bernd Dehning
  • Bettina Mikulec
  • Brennan Goddard
  • Burkhard Schmidt
  • Daniel Wollmann
  • Dave Charlton
  • Davide Tommasini
  • Detlef Kuchler
  • Didier Claude Contardo
  • Django Manglunki
  • Doris Forkel-Wirth
  • Elena Shaposhnikova
  • Elias Metral
  • Emilio Meschi
  • Erk Jensen
  • Eugenia Hatziangeli
  • Ezio Todesco
  • Fabiola Gianotti
  • Federico Antinori
  • Francesco Bertinelli
  • Francesco Cerutti
  • Francois Duval
  • Frank Zimmermann
  • Frederick Bordry
  • Gianluigi Arduini
  • Gijs De Rijk
  • Giovanni Iadarola
  • Giovanni Rumolo
  • Giulia Papotti
  • Hannes Bartosik
  • Heiko Damerau
  • Helmut Burkhardt
  • Jean-Baptiste Lallement
  • Jean-Paul Burnet
  • Jean-Philippe Tock
  • Joe Incandela
  • Johannes Peter Wessels
  • John Jowett
  • John Seeman
  • Jorg Wenninger
  • Jose Miguel Jimenez
  • Karel Cornelis
  • Katsunobu Oide
  • Katy Foraz
  • Klaus Hanke
  • Laurent Jean Tavian
  • Laurette Ponce
  • Lisette Van Den Boogaard
  • Livio Mapelli
  • Luca Bottura
  • Lucio Rossi
  • Malika Meddahi
  • Maria Chamizo Llatas
  • Markus Brugger
  • Markus Zerlauth
  • Massimiliano Ferro-Luzzi
  • Massimo Giovannozzi
  • Maurizio Vretenar
  • Max Klein
  • Michael Benedikt
  • Mike Lamont
  • Mirko Pojer
  • Nicolas Gilbert
  • Oliver Bruning
  • Olivier Brunner
  • Paolo Ferracin
  • Paolo Fessia
  • Paolo Giubellino
  • Paul Collier
  • Philip Patrick Allport
  • Philippe Baudrenghien
  • Philippe Bloch
  • Pierluigi Campana
  • Pierre Charrue
  • Qing Qin
  • Ralf Trant
  • Rama Calaga
  • Rende Steerenberg
  • Reyes Alemany Fernandez
  • Riccardo De Maria
  • Richard Jacobsson
  • Rob Van Weelderen
  • Roberto Losito
  • Roberto Saban
  • Rogelio Tomas Garcia
  • Roland Garoby
  • Serge Claudet
  • Sergio Bertolucci
  • Shauna Dillon
  • SIEMKO Andrzej
  • Sigurd Lettow
  • Simone Gilardoni
  • Stefano Redaelli
  • Stephane Fartoukh
  • Steve Myers
  • Steven Hancock
  • T. Bohl
  • Thomas Roser
  • Tiziano Camporesi
  • Verena Kain
  • Volker Mertens
  • Werner Herr
  • Werner Riegler
  • Wolfgang Hofle
  • Wolfram Fischer
  • Yannis Papaphilippou
    • 08:30
      Welcome coffee
    • 1
      Introduction
      Speaker: Steve Myers (CERN)
      Slides
    • Session 1 - Experiments
      Conveners: Austin Ball (CERN), Mike Lamont (CERN)
      • 2
        Highlights from ECFA (20' + 10')
        Speaker: Austin Ball (CERN)
        Slides
        summary
      • 3
        Physics Landscape - (20' + 10')
        Abstract: The discovery of a Higgs boson at the LHC Run 1 represents a major breakthrough in particle physics and outlines a roadmap for the future LHC programme. Measurements of this new particle with increasing precision (in particular its couplings to fermions and bosons and its self-couplings), as well as vigorous searches for other Higgs bosons, are needed to sharpen our understanding of the electroweak symmetry breaking mechanism and to establish if the Higgs sector consists of one or more scalars. Also important is to verify that the newly discovered particle restores unitarity of vector-boson scattering at high mass, which represents a crucial “closure test” of the Standard Model. The issue of the Higgs boson mass, namely whether it is “natural” (i.e. stabilised by a new symmetry) or fine-tuned, requires searches for physics beyond the Standard Model in the few TeV energy region. These searches are also motivated by other compelling questions, such as the nature of dark matter and the flavour/family problem. This talk reviews the physics potential of ATLAS and CMS in the years to come, covering both the period until LS3 and the post-LS3 era. Integrated luminosities of 300 fb-1 and 3000 fb-1 are assumed in the two cases, respectively. Comparisons with a scenario where the integrated luminosity is limited to 1000 fb-1 (as expected without a Phase-2 upgrade of the LHC accelerator), and with the potential of new machines being discussed in the high-energy physics community, are also presented.
        Speaker: Fabiola Gianotti (CERN)
        Slides
      • 4
        Detector Limits (20' + 10')
        Abstract: This contribution will cover all the aspects of system limits in the high-luminosity detectors. Both the limits connected to luminosity/radiation and the ones connected to ageing/lifetime aspects of the equipment over the next 10-15 years. Considerations will be presented on the ability to deal with HL-LHC luminosity and the pattern of interventions to achieve the full exploitation of the increased accelerator performance. A discussion on the upgrades in terms of Performance Improvement Consolidation and absolutely essential consolidations will be presented.
        Speaker: Beniamino Di Girolamo (CERN)
        Slides
      • 10:45
        Coffee break
      • 5
        Performance parameters - experiments' perspective (20' + 10')
        Abstract: The upgrades of the ATLAS and CMS experiments will be accomplished in three stages during the long shutdowns foreseen for the upgrades of the LHC. In LS1, the CM energy will be increased to 13TeV (or slightly higher), and it is expected that the bunch spacing will be reduced to 25 ns for future RUNs. It is anticipated that the peak luminosity can exceed the nominal value of 1x1034 Hz/cm2 before LS2 and reach more than 2x1034 Hz/cm2 after LS2. The experiment upgrades during LS1 will allow completing the original detector designs, consolidate operation and prepare for the higher luminosities. In the period through LS2 the upgrades will be completed for operation at a pile-up (PU) of 50 proton collisions per bunch crossing, as a baseline. In LS3 the LHC itself will be upgraded to optimize the bunch overlap at the interaction region. It is expected that the peak luminosity, exceeding 1035 Hz/cm2 at the beginning of the fills, will be levelled at 5 x 1035 Hz/cm2 to maintain PU below 140. The goal for the High Luminosity LHC is to deliver a further 2500 fb-1 in the decade after LS3. Atlas and CMS will need major upgrades during this shutdown to solve detector and system aging, high occupancy and radiation hardness issues, mitigate pile-up effects and enhance performance where statistics/systematics limited. This paper focuses on the mitigation of the high rate and pile-up effects, as achieved through the design goals of the upgraded detector and trigger systems, or in the operation of the experiments. It will discuss the current knowledge of performance degradation with increasing PU for the different RUN periods and will address the experimental constraints on the luminous region length and the PU density.
        Speaker: Didier Claude Contardo (Universite Claude Bernard-Lyon I (FR))
        Paper
        Slides
      • 6
        Plans and physics outlook for non-high luminosity experiments until and after LS3 (20' + 10')
        Abstract: Based on the current physics scene, the future holds more than ever a joint enterprise of precision measurements and direct searches. With its very broad scientific program of heavy flavour precision measurements both in the beauty and the charm sector, as well as forward electroweak precision physics, LHCb has demonstrated to be a powerful forward general purpose detector complementary to ATLAS and CMS. After the expected lifetime of 10 /fb for the current experiment, the precision of most measurements will still be limited by statistics. Experience from Run I shows that systematic uncertainties are not expected to limit the precision down to the theoretical uncertainties. LHCb will thus undergo a major upgrade in LS2 to the ultimate flexibility of a full software trigger, together with a sub-detector configuration which should allow improving the physics yield up to an instantaneous luminosity of 2x10^33 cm-2s-1, with the goal to collect an integrated luminosity of 50-100 /fb by 2028. The flexibility of the upgrade also prepares LHCb for any changes in the physics scene beyond LS2. The ion program is an important aspect of the complete LHC physics program. For the purpose of detector commissioning and calibration, and physics normalization, the ALICE experiment requires data taking during high-luminosity proton-proton physics. This will evolve with the major upgrade of ALICE which is currently planned for LS2. In view of the LHC and the injector upgrades, this paper reviews the physics motivations, the upgrade and consolidation programs, and the operational requirements and schedule for LHCb and for the ALICE proton-proton data taking. For completeness, it also covers the impact and aspects of the LHC forward physics program which are relevant for the upgrades of the LHC and the injector complex. In particular it will try to identify any incompatibility with the requirements of the special forward physics runs.
        Speaker: Richard Jacobsson (CERN)
        Paper
        Slides
      • 7
        Post LS1 Schedule (20' + 10')
        Abstract: The scheduling limits for a typical long year taking into account technical stops, machine development, special physics runs are presented. An attempt is then made to outline a ten year post LS1 schedule taking into account the disparate requirements outlined in the previous talks in this session. The demands on the planned long shutdowns and the impact of these demands on their proposed length will be discussed. The option of using ion running as a pre-shutdown cool-down period will be explored. The performance improving consolidation (PIC) and full upgrade scenarios will be introduced as a lead-in to the following sessions.
        Speaker: Mike Lamont (CERN)
        Paper
        Slides
    • 12:45
      Lunch
    • Session 2 - Post LS1 scenarios without and with LINAC4
      Conveners: Gianluigi Arduini (CERN), Steven Hancock (CERN)
      • 8
        Expected performance in the injectors at 25 ns without and with LINAC4 (30' + 10')
        Abstract: The quality of the 25 ns beams that can be delivered at the LHC injection is determined by the injection process into the PSB, as well as by space charge, collective interactions, electron cloud and RF power limitations in the PS and SPS. Using the information available from our present experience, the main goal of this presentation is twofold: (1) to assess the intensity and brightness reach of the 25 ns beams produced by the LHC injector chain with the traditional scheme, before and after the connection of the PSB to Linac4; and (2) to identify which bottlenecks will be likely to limit the performance with Linac4. A few options to maximize the potential of the increased brightness provided by Linac4, based on flattened bunch profiles at the PS injection or the use of alternative production schemes, will be included in the analysis.
        Speaker: Giovanni Rumolo (CERN)
        Paper
        Slides
      • 9
        Integrated performance of the LHC at 25 ns without and with LINAC4 (30' + 10')
        Abstract: The performance of the LHC above 6.5 TeV will depend on many factors. The available beams and their brightness defines together with achievable beta* the potential peak luminosity. For some cases the peak luminosity and the associated event pile-up may degrade the quality of the data recorded by the experiments. Such cases will require luminosity leveling for which a number of options are available. The peak performance may also be limited by cooling capacities and other equipment related issues, including machine protection as well as UFOs. The 25 ns beams require in addition substantial periods of scrubbing. The performance of the LHC in terms of integrated luminosity will be evaluated for various scenarios involving 25 ns beams, taking into account potential limitations from the various sources.
        Speaker: Jorg Wenninger (CERN)
        Paper
        Slides
      • 15:50
        Coffee Break
      • 10
        Required maintenance and consolidation to run like that (injectors and LHC) until 2035? (30' + 10')
        Abstract: Assuming that Linac4 is connected to the PSB in LS2, we will outline the maintenance and basic consolidation works that will be needed to maintain design performance of the LHC and its Injector chain until 2035, with an overall reliability as good as that achieved in the first LHC operation period 2009 to 2013. Using these data we will estimate the shutdown schedule needed throughout this period to complete these maintenance and consolidation works. These estimates will also include the required radiation cool-down periods, time for system re-commissioning and testing as well as the time needed to restart the accelerator chain for LHC colliding beam operation. As some of the consolidation activities needed for the PS and SPS machines are related to the radiation dose taken by the machine equipment (e.g., irradiated cable replacement and magnet renovation) the variation of these time estimates as a function of beam losses in the Injector chain will also be covered.
        Speaker: Katy Foraz (CERN)
        Paper
        Transparents
      • 11
        What could stop us,when and how long? (15' + 10')
        Abstract: The life of the LHC accelerator magnets, much as any other classical electrical machine, is limited in time. This is especially true because the LHC is subjected to significant radiation and cycled electrical stress. The aim of this talk is to review the life limits of the LHC magnets, and provide an estimate for the failure risks at the time horizon of 2020 and beyond, in the hypothesis that no consolidation action, other than normal maintenance, is taken. We consider in particular the magnets at critical locations and subjected to radiation load, either from luminosity debris (IR quadrupoles, orbit and high order corrector packages, warm separation dipole D1), or beam losses at collimators (warm quadrupoles MQW). We also attempt to draw conclusions from electrical fault statistics and electrical quality assurance measurements and their implications for the life of the electrical circuits.
        Speaker: Luca Bottura (CERN)
        Paper
        Slides
      • 12
        Free time for discussions
    • 18:30
      Apéritif
    • 19:30
      Social Dinner
    • Session 3: PICs and Upgrade scenario 1 : Session 3A - Adding Performance improving consolidation
      Conveners: Lucio Rossi (CERN), Malika Meddahi (CERN)
      • 13
        INJECTORS: PICs: what are we talking about? (20' + 10')
        Abstract: This presentation will identify PIC activities for the LHC injector chain, and point out borderline cases to pure consolidation and upgrade. The most important PIC items will be listed for each LIU project (PSB, PS, SPS) and categorized by a) the risk if not performed and b) the implications of doing them. This will in particular address the consequences on performance, schedule, reliability, commissioning time, operational complexity etc. The additional cost of PICs with regard to pure consolidation will be estimated and possible time lines for the implementation of the PICs will be discussed. In this context, it will be evaluated if the PICs can be implemented over several machine stops.
        Speaker: Klaus Hanke (CERN)
        Paper
        Slides
      • 14
        LHC: PICs: what are we talking about? (20' + 10')
        Abstract: This talk will provide an overview of the PICs putting in evidence when they are needed and the possible timeframe they would require for the installation. The performance improvements, respect to a pure consolidation, will be highlighted while trying to provide an evaluation of the risks involved in the installation or in delaying it. The contribution of the PICs to the machine reliability will be underlined as this is one of the key parameter to reach the HL-LHC target. An overview of involved cost estimates will be provided according to present knowledge.
        Speaker: Paolo Fessia (CERN)
        Paper
        Slides
      • 15
        LIU-HL_LHC: PICs: what do we gain in beam performances? (20' + 10')
        Abstract: The beam parameters in the LHC and its injectors resulting from the Performance Improvement Consolidation (PIC) activities presented in the previous two talks will be reviewed and motivated assuming that LINAC4 will be operational as PS-Booster Injector. The corresponding limitations in the accelerator chain will be outlined. Based on the above performance an estimate of the LHC integrated luminosity by 2035 will be provided taking into account, whenever possible, the expected gain in reliability resulting from the consolidation campaign and the requirements in terms of shut-down time for its implementation. The evaluation of the need and extent of the performance and reliability improvement for some of the PIC items might imply additional information: the necessary machine studies and the specific operational experience required during Run 2 will be summarized.
        Speaker: Gianluigi Arduini (CERN)
      • 10:00
        Coffee Break
    • Session 3: PICs and Upgrade scenario 1 - Session 3B - Upgrade scenario 1
      Conveners: Lucio Rossi (CERN), Malika Meddahi (CERN)
      • 16
        HL-LHC: How to achieve Upgrade Scenario 1 goals in the LHC? (20' + 10')
        Abstract: The presentation discusses the options for maximizing the performance reach of a limited HL-LHC upgrade scenario and for reaching the performance goals of the Upgrade Scenario 1 based on Performance Improving Consolidation (PIC) (e.g. new triplet magnets) and only moderate upgrade implementations (e.g. Long Range Beam-Beam Wire compensators and Higher Harmonic RF system but no Crab Cavity system). The presentation will summarize the required key beam parameters and performance issues (e.g. required machine efficiency and run scheduling), discuss the cost and calendar implications for the Upgrade Scenario 1 option and discuss the trade-off between different upgrade options (e.g. Long Range Beam-Beam Wire compensators and Higher Harmonic RF system).
        Speaker: Oliver Bruning (CERN)
      • 17
        Work effort in the LHC accelerator for upgrade scenario 1 (20' + 10')
        Abstract: We will review the main baseline for the LHC upgrade scenario 1, pointing out the main choices for the magnets in terms of apertures, field, gradients, operational currents, cooling, heat loads, radiation damage and integration aspects. The main reasons behind these choices will be reviewed, with special emphasis on risk, cost, and commissioning time. The options which are still open will be discussed. The foreseen distribution of work within the collaboration is also presented.
        Speaker: Ezio Todesco (CERN)
        Paper
        Slides
      • 18
        LIU: Which beams in the injectors fulfil HL-LHC Upgrade Scenario 1 goals? (20' + 10')
        Abstract: The talk will summarize the current understanding of the issues to be addressed in the injectors in order to fulfil the requirements of the HL-LHC in the framework of the upgrade scenario 1. The required beam parameters in the different accelerators will be outlined, and the relevant performance limitations described. Possible beam production schemes will be presented, and their relative merits will be compared. The upgrades required in the preferred scenario will be described and the beam characteristics potentially accessible at LHC injection will be estimated.
        Speaker: Simone Gilardoni (CERN)
        Paper
        Slides
      • 19
        Work Effort in the LHC Injector Complex, including Linac4 connection, for the Upgrade Scenarios (30' + 10')
        Abstract: This presentation will describe the work for the Linac4 connection, PSB, PS and SPS that is required for upgrade scenario 1. It will be shown that the requirements on the hardware work needed for upgrade scenario 1 is identical to the ones of the upgrade scenario 2. The Linac4, presently under construction, will replace the present Linac2 as injector of the CERN proton accelerator complex. The connection of the Linac and the commissioning of the transfer line and of the PS Booster H- injection will require a proton complex shut-down of several months. Possible scenarios for allowing a Pb-Pb run in LHC during this period will be described. The various activities through the injector chain will be detailed as well as their dependencies and an estimate given for the duration of the necessary shutdowns and recommissioning periods with beam. It will be mentioned whether some decisions are still to be taken and are related to information to be obtained after LS1. Another important aspect will be the evaluation of the risks related to the upgrade interventions and operational complexity, which concern schedule, beam characteristics as well as reliability and overall performance. It will be studied if part of the activities could be spread out over several machine stops, and as conclusion the preferred scenario will be presented.
        Speakers: Bettina Mikulec (CERN), Jean-Baptiste Lallement (CERN)
    • 12:40
      Lunch
    • Session 4 - Upgrade scenario 2 (decoupled from scenario 1)
      Conveners: Dr Brennan Goddard (CERN), Roland Garoby (CERN)
      summary
      • 20
        How to maximize the HL-LHC performance (HL-LHC)? (20' + 10')
        Abstract: The contribution presents the baseline HL-LHC upgrade options (25ns LIU parameters, large aperture triplets, crab cavities) among the options that can maximize the LHC performance after LS3. The analysis covers the preservation of the LIU beam parameters from the injection process to stable conditions for physics, the minimization of the luminous region volume while preserving the separations of multiple vertices, the luminosity control mechanisms to extend the duration of the most efficient data taking conditions together with the associated concerns (machine efficiency beam instabilities, halo population, cryogenic load, beam dump frequency) and risks (failure scenarios, radiation damages). In conclusion the expectations of the integrated luminosity per fill and year are presented.
        Speaker: Riccardo De Maria (CERN)
        Paper
        Slides
      • 21
        Can we ever reach the HL-LHC requirements with the injectors (LIU)? (30' + 10')
        Abstract: The present intensity and brightness limitations of the LHC injector synchrotrons for 25 ns beams are space charge, beam loading, instabilities in the transverse and longitudinal planes and electron cloud effects. This paper reviews how these performance limitations are expected to change after implementing the mitigation measures foreseen within the Upgrade Scenario 2. The question is addressed whether the beam performance will match the requirements of the HL-LHC project. In particular, we assume operational scenarios with 25 ns beams produced with the traditional bunch splitting scheme in the PS and with the already tested batch compression scheme beams. A set of baseline parameters at LHC injection is then established based on extrapolation from the beam characteristics achieved in 2012 and the expected gains from the upgrades.
        Speaker: Hannes Bartosik (Physics Division)
        Paper
        Slides
      • 22
        How to implement all the HL-LHC upgrades (HL-LHC)? (20' + 10')
        Abstract: The luminosity upgrade will require major changes in the LHC machine configuration: about 1.2 km of the machine will undergo major renovation or modification. In the talk we will review the list of all equipment foreseen to be replaced or additionally installed as new. We will review the plan of all upgrades that should start already prior to LS2 (with the installation of the first SC link and the cryo-plant in P4), through to the major works in LS3, synchronized with an upgrade of the LHC detectors. Best estimates of the required duration of the various shutdowns will be discussed, and also the main risks and their mitigation.
        Speaker: Lucio Rossi (CERN)
        Paper
        Slides
      • 23
        HL-LHC: Exploring alternative ideas (20' + 10')
        Abstract: The HL-LHC parameters assume unexplored regimes for hadron colliders in various aspects of accelerator beam dynamics and technology. This talk reviews various alternatives that could potentially improve the LHC performance, for example: the use of e-lens to compensate the beam-beam head-on interaction, the use of optical or coherent electron cooling to reduce the beam emittance (at top energy and at injection), the use of higher harmonic RF systems to improve Landau damping or alternative bunch schemes or even smaller beta*. The alternatives are assessed in terms of feasibility, pros and cons, risks versus benefits and the impact on beam availability.
        Speaker: Rogelio Tomas Garcia (CERN)
        Paper
        Slides
      • 16:10
        Coffee Break
      • 24
        LIU: Exploring alternative ideas (20' + 10')
        Abstract: The baseline upgrade scenarios for the injector complex cover the connection of Linac4 to the PSB, the increase of the PSB-PS transfer energy from 1.4 GeV to 2 GeV and the major SPS RF upgrade during LS2. The achievable beam characteristics will nonetheless remain below the expectation of the HL-LHC project. Therefore, alternative or additional options like, e.g., special bunch distribution, the use of injection optics optimized for high space charge or extra RF systems will be discussed. The expected beam parameters, possible implementation and impact on beam availability for these more exotic options will be analysed and compared to the LIU baseline plan. Moreover, the potential interest of further batch compression schemes will be evaluated.
        Speaker: Heiko Damerau (CERN)
      • 25
        How to reach the required availability of LHC to reach the required level? (20' + 10')
        Abstract: The HL-LHC has ambitious integrated luminosity goals in the region of 250 inverse femtobarn per year. This level of performance will required excellent machine availability. After a definition of terms and assumptions, the availability to date is reviewed while noting the importance of accurate and reliable tracking. The present consolidation strategy is outlined and the potential benefits highlighted. Other possible areas of improvement and future challenges which could impact the overall availability are then discussed. Estimates based on extrapolation from present experience are given. Injector availability will also be important for the overall LHC performance and the need for sustained, well-planned consolidation is recalled.
        Speaker: Mike Lamont (CERN)
        Paper
        Slides
      • 26
        50 ns back-up scenario (30'+10')
        Abstract: The baseline bunch spacing for LHC high luminosity proton-proton operation after LS1 is 25 ns to maximize the integrated luminosity while keeping pile-up low. The success of this mode of operation is not guaranteed. Electron cloud, UFOs, long-range beam-beam, heating and other effects might make 25 ns operation in the LHC and/or the injectors difficult. This talk will review possible show-stoppers in the LHC and injectors for 25 ns operation and discuss possible remedies such as coating in the SPS. An alternative would be re-considering 50 ns operation. A possible way of how to operate with 50 ns taking pile-up limits and integrated luminosity goals for the different upgrade scenarios into account will be presented. The question of when to decide at the latest between 25 ns and 50 ns to upgrade hardware accordingly will also be addressed.
        Speaker: Dr Verena Kain (CERN)
        Paper
        Slides
    • Session 5 - IONS
      Conveners: Massimiliano Ferro-Luzzi (CERN), Oliver Bruning (CERN)
      slides
      • 27
        INFORMATION ONLY - Already in session 3 - Work Effort in the LHC Injector Complex, including Linac4 connection, for the Upgrade Scenarios
        Abstract: This presentation will describe the work for the Linac4 connection, PSB, PS and SPS that is required for upgrade scenario 1. It will be shown that the requirements on the hardware work needed for upgrade scenario 1 is identical to the ones of the upgrade scenario 2. The Linac4, presently under construction, will replace the present Linac2 as injector of the CERN proton accelerator complex. The connection of the Linac and the commissioning of the transfer line and of the PS Booster H- injection will require a proton complex shut-down of several months. Possible scenarios for allowing a Pb-Pb run in LHC during this period will be described. The various activities through the injector chain will be detailed as well as their dependencies and an estimate given for the duration of the necessary shutdowns and recommissioning periods with beam. It will be mentioned whether some decisions are still to be taken and are related to information to be obtained after LS1. Another important aspect will be the evaluation of the risks related to the upgrade interventions and operational complexity, which concern schedule, beam characteristics as well as reliability and overall performance. It will be studied if part of the activities could be spread out over several machine stops, and as conclusion the preferred scenario will be presented.
        Speakers: Bettina Mikulec (CERN), Jean-Baptiste Lallement (CERN)
        Slides
      • 28
        Experiment perspective (20' + 10')
        Abstract: The Presentation summarizes the ion physics achievements so far and gives an outlook of the physics needs for the next 10 years including a summary of the required beam types and configurations (e.g. p-Pb and collision energies other than the nominal 13 TeV) and what, if any, other ion species than Pb are being considered. The presentation will also present the experiment expectations in terms of integrated luminosities and will discuss the impact - usefulness, or otherwise, of different scheduling options on the Ion physics program. Different ion running scenarios, as well as the usefulness of an extended ion run, in light of the upgrade plans and goals are discussed in terms of integrated luminosity and physics targets.
        Speakers: Benedetto Gorini (CERN), Emilio Meschi (CERN)
        Paper
        Slides
      • 29
        Performance of the injectors with ions after LS1 (25' + 15')
        Abstract: We review the performance of the ion injector chain at the light of the improvements which will take place during LS1, and we derive the expected luminosity gain for Pb-Pb and p-Pb collisions in the LHC. We suggest a baseline plan of upgrades that will allow the requirements of the ALICE experiment after LS2 to be reached. An alternative plan is also presented. Finally, we examine the possibility for different ions species for which some of the other experiments have expressed an interest. The main outcomes of the presentation ‘Work effort in the injector complex (including the Linac4 connection)’ will be reminding with emphasis on their consequences on the ion operation.
        Speaker: Django Manglunki (CERN)
        Paper
        Slides
      • 10:10
        Coffee Break
      • 30
        How to run ions in the future? (20' + 10')
        Abstract: In the light of different running scenarios potential source improvements will be discussed (e.g. one month every year versus two month every other year and impact of the different running options [e.g. an extended ion run] on the source). As the oven refills cause most of the down time the oven design and refilling strategies will be presented. A test stand for off-line developments will be taken into account. Also the implications on the necessary manpower for extended runs will be discussed.
        Speaker: Detlef Kuchler (CERN)
        Paper
        Slides
      • 31
        Future heavy-ion performance of the LHC (30' + 10')
        Abstract: The evolution of the Pb-Pb and p-Pb luminosities of the LHC, and the efficiency with which available operating time can be exploited, will depend on the timing of various upgrades of the injectors, the collider and the experiments. Data from the first Pb-Pb operation at 6.5 Z TeV per beam will be crucial in clarifying the roles of quench limits and the needs for counter-measures. Using the best information now available, estimates of the integrated luminosities from LS1 onwards will be given, taking account of the progress of upgrades. The possibility of additional Pb-Pb operation during the connection of Linac4 to the PS Booster is discussed.
        Speaker: John Jowett
        Paper
        Slides
    • 12:00
      Lunch
    • Session 6 - Close Out
      Conveners: Dr Frank Zimmermann (CERN), Steve Myers (CERN)
      • 32
        Session 1 Summary
        Speakers: Austin Ball (CERN), Mike Lamont (CERN)
        Paper
        Slides
      • 33
        Session 2 Summary
        Speakers: Gianluigi Arduini (CERN), Steven Hancock (CERN)
        Paper
        Slides
      • 34
        Session 3 Summary
        Speakers: Prof. Lucio Rossi (CERN), Malika Meddahi (CERN)
        Paper
        Slides
      • 35
        Session 4 Summary
        Speakers: Dr Brennan Goddard (CERN), Roland Garoby (CERN)
        Paper
        Slides
      • 36
        Session 5 Summary
        Speakers: Massimiliano Ferro-Luzzi (CERN), Oliver Bruning (CERN)
        Slides
        summary
      • 15:15
        Coffee Break and Group Photo
      • 37
        Close Out Summary
        Speakers: Dr Frank Zimmermann (CERN), Steve Myers (CERN)
        Paper
        Slides