1. Design Study High Luminosity LHC (HL-LHC)
Collaborative Project
FP7-INFRASTRUCTURE-2010
By Lucio Rossi – CERN
1st CERN 20 July

2. LHC and EU Particle Physics Lisbona 2006
The European strategy for particle physics …
Scientific activities
3. The LHC will be the energy frontier machine for the
foreseeable future, maintaining European leadership in the
field; the highest priority is to fully exploit the physics potential
of the LHC, resources for completion of the initial programme
have to be secured such that machine and experiments can operate
optimally at their design performance. A subsequent major
luminosity upgrade (SLHC), motivated by physics results
and operation experience, will be enabled by focussed R&D;
to this end, R&D for machine and detectors has to be vigorously
pursued now and centrally organized towards a luminosity
upgrade by around 2015.
Statement is perfectly actual and valid
However the date must be shifted 5 years
1 y of delay in LHC and detector commissioning
2 y for the incident and for next splice consolidation
2 y more of operation to reach ~500 fb-1 (Int. Lumi per year ~ 50 fb-1, not 100 !)
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L. Rossi - HL-LHC Design Study

3. L. Rossi - HL-LHC Design Study
The baseline in
Radiation damage limit ~700 fb-1
Paper of J. Strait et al. PAC2003
Need of change in Main hardware:
HF Quadrupole magnets for T
New program (in // to LHC construction)
US-LARP in US in 2003 (6 MCHF/y ) – based on a Nb3Sn DOE program
FP6-CARE : NED JRA to develop EU Nb3Sn in Its positive effects NOW!
FP7 EuCard IA: WP on HFM
In 2007 new – anticipated – scenario :
Nb3Sn not ready before
Decision to target a first upgrade in
Phase 1 based on Nb-Ti Ø=120 mm
FP7 SLHC-PP launched for
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L. Rossi - HL-LHC Design Study

4. Updated LHC lumi vs. (end of) year
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L. Rossi - HL-LHC Design Study
Courtesy of M. Lamont, spring 2010

5. MTP “Observations from the DG”
From S. Myers
Thus, the MTP assumes the feasibility of the energy upgrade of the PS Booster and does not include the start of the LP-SPL and PS2 construction as of 2013
In order to optimize the strategy towards the HL-LHC, with the goal of maximizing the integrated luminosity useful for physics, Management has set up a task force. A preliminary recommendation from this task force is to delay the inner triplet replacement to a single HL-LHC upgrade around 2020.
Now at CERN a project has been set lead by Lucio Rossi (Oliver Bruning, deputy).
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L. Rossi - HL-LHC Design Study

6. What needs for average lumi 5x1034 New lay-out of some part of LHC
Improve some correctors
A the lattice sextupoles
New MQT corrector scheme using existing spare 600 A bus bars
Re-commissioning DS quads at higher gradient
Review MSs
Change of New Q5/Q4 (larger aperture), with new stronger corrector orbit, displacements of few magnets
Larger aperture D2
(may be other actions, more quads in points 6 and 7)
Displacement of Power Converters & DFBs at least of Inner Triplets but also of OTHER equipment on surface by means of SC links.
Cryo-plant for RF in point 4 : K
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L. Rossi - HL-LHC Design Study

7. The main ingredient of the upgrade IR Quads
High Gradient/Large Aperture Quads, with Bpeak T. Higher field quadrupoles translate in higher gradient/shorter length or larger aperture/same length or a mix . US-LARP engaged to produce proof by Construction is 1 year more than Nb-Ti : by 2018 is a prudent assumption.  as small as 22 cm are possible with a factor 2.5 in luminosity by itself, if coupled with a mechanism to compensate the geometrical reduction. If a new way of correcting chromatic aberration could be found,  as small as cm can be eventually envisaged.
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L. Rossi - HL-LHC Design Study

8. L. Rossi - HL-LHC Design Study
HF Nb3Sn Quad
Nb3Sn is becoming a reality (first LQ long -3.6 m – quad 90 mm)
This year we expect a second LQ and a 1 m long mm aperture model
In 3 years: 4-6 m long magnets, 120 mm ap., G= T/m
4.5 K
~3 K
1.9 K
Note: LQS01 & TQS02
use same strand design
(RRP 54/61)
200 T/m
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L. Rossi - HL-LHC Design Study

9. The main ingredient of the upgrade RF Crab cavities
Crab Cavities: this is the best candidate for exploiting small  (for  around nominal only +15%). However it should be underlined that today Crab Cavities are not validated for LHC , not even conceptually: the issue of machine protection should be addressed with priority.
Global Scheme. 1 cavity in IP4, Proof on LHC, good for 1 X-ing.
Semi-global; it may work!(JP Koutchouck)
Local scheme; 1 cavity per IP side. Maybe local doglegs needed.
Early Separation Scheme could be an alternative (or a complement)
Both scheme, Crab Cavities and ESS provide a simple mean to do levelling
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L. Rossi - HL-LHC Design Study

10. L. Rossi - HL-LHC Design Study
Crab Cavities qc
Elliptical 800 MHz not far from being designed. Require 400 mm beam-beam
400 MHz small cavity under conceptual study, they can (?) fit in 194 mm beam-beam. Required for final solution
Ref. : F. Zimmermann, Ed Ciapala
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L. Rossi - HL-LHC Design Study

11. Making the system capable to swallow 2-4 kW per IP
New Cryoplants in IP1 & IP5: for power AND to make independent Arc- IR: K scales as K (for 1 set of cold compressor)
Special dedicated collimation system (also for background) and Machine protection
Robotics for remote manipulation
Dismantling present Triplet
Installation HL-LHC
Maintenance
Dismounting HL-LHC ???
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L. Rossi - HL-LHC Design Study

12. It is new entire project  we need a Design Study
The work od SLHC-PP has been essential to arrive to thsi pointz and most of it will be used
Scope of the HL-LHC DS:
Carry out the study to produce a consistent design to reach with levelling, allow LHC to reach the goal of 1000 fb-1 by 2025
Exploring in details all solutions and paths for the upgrade, both in terms of LHC operational mode and hardware changes
Producing by end 2013 a PDR (Preliminary Design Report) enabling the CERN Council, to make a choice about the configuration of LHC upgrade.
Producing by end of 2014/half 2015 a TDR (Technical Design Report) of the selected path for the upgrade defining the maximum goal for the LHC luminosity
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L. Rossi - HL-LHC Design Study

13. L. Rossi - HL-LHC Design Study
New CERN plan Already in: new Cryo P4 CC in P4 – possibly 11 T dipole for DS in 2016
HL-LHC is well anchored in the program of CERN.
However the prgram may suffer from reduction of budget, shift in the LHC schedule…
But it may be required to compensate SHORTFALL in LHC…
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L. Rossi - HL-LHC Design Study

14. L. Rossi - HL-LHC Design Study
Resources
10 M€ total cost over 4 years: July
Reimbursment by EU
40% may be reimbursed by EU
CERN offers by free the technical development, but will be reimbursed 100% for management. Exception for fellow?
We need to use EuCard (and other program)
Most of resources on personnel
Some hardware, especially for orphan items
Generate positive attitude in other labs:
KEK has put (with no engagments 10 MCHF + 50 MCHF for HL-LHC-Magnets R&D and construction…)
US-LARP Magnets R&D is perhaps getting reinforced …
Non EU labs can participate to governance (but no EU funds)
The names herein are CERN coordinators: each of it will be joined by a non-CERN coordinator. Except project Coordinator, the co-ordinator ijn charge for two years, nominate by the governing board.
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L. Rossi - HL-LHC Design Study

15. WP 1 – Management Lucio Rossi
Main tasks
General management of the DS and link with other similar entities outside EU
General plan and coherence of the parameters
Risk Analysis and mitigation plans
Coordination with the LHC machines performance and planning
LHC INJ requirements
Coordination with Physics requirement
Link to outside partner
Synergy with HE-LHC design feature
Outreach and dissemination
Radioprotection & Legal
Enviroment impact
Participant: CERN
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L. Rossi - HL-LHC Design Study

16. WP2 – Beam Physics and Lay-out Oliver Bruning
Topics:
Investigate the parameter space: optics (beta*, beta* aspect ratio) and “moderately” the beam parameters (beam pattern, bunch charge, emittance, bunch length) to establish a baseline corresponding to a peak luminosity ≥ 5E34 without head-on collision tools (crab-cavities, D0 or b-b wire) .
Specify, organise and participate to dedicated LHC machine studies to validate some specific aspects the proposed baseline (e.g. off-momentum beta-beating correction, two-stages squeeze concept of the low-beta IR’s and flat beam optics).
Study and establish a short list of additional ingredients (head-on collision tools, more aggressive beam parameters, e.g. so-called LPA scheme) to reach the integrated luminosity goal (5E34 average lumi per coast after levelling).
Develop and maintain consistency in the parameters and modelling for any kind of beam dynamics studies (dynamic aperture, beam-beam and dedicated studies in collaboration with the collimation and crab-cavity work-packages):
Develop new physical model and numerical tools (e.g. beam-beam kick induced by a fully 6D coupled strong beam for simulations with crab-cavities).
Provide a consistent infrastructure (HL-LHC sequence, optics, aperture model, model for magnet field imperfections, Mad-X reference jobs).
Interface with WP3 to specify the main parameters and layout of the HL-LHC new magnets (IT, D1, D2, Q4) and additional hardware modifications or tests needed in the LHC Ring (magnet re-commissioning at higher than nominal currents, layout modifications in other LHC insertions as IR6 or IR4).
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L. Rossi - HL-LHC Design Study

17. L. Rossi - HL-LHC Design Study
WP 2 cont.
Partners
CERN
US LARP
KEK
INFN
CEA-CNRS
UK (CKI) ?
German Universities KIT ?
ES (Valencia) ?
PSI ? EPFL ?
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L. Rossi - HL-LHC Design Study

18. WP3 -Magnet Design Ezio Todesco
Main topics
Magnet lay-out modification (with WP2)
NbTi assesment and parameters for IR and MSs
New Magnet Corrector Design
NbSn assessment and parameters for IR and DS
Assessment of new technology for IR (HTS for magnetized TAS, etc…)
Sc links and PC relocation
Synergy with HE-LHC technolgy
Participation
CERN
UniGe
CEA
INFN
Uni SouthHampton
US-LARP
KEK
STCF-RAL ?
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L. Rossi - HL-LHC Design Study

19. WP4: Crab Cavity Design (1/2) Ed Ciapala
Main cavity topics:
Design optimization for novel schemes (minimum # of peripherals)
Cavity and cryomodule specifications (LHC report)
Simulations (Couplers, tuner, MP, mechanical, thermal, …)
Fabrication and measurements on copper models field profile, impedance, errors)
Demonstration of field gradients in compact cavities (4 structures)
Q-slope, onset of field emission and quench
Performance, decide between 2K and 4K
Coupler and tuner development and testing
Study of mech. resonances, microphonics
Performance with couplers and horizontal cryostat
Performance with beam (e.g. SPS - impedance, collimation)
Interlocks and fast Feedback (other measures like Qext)
Common power and cryogenic systems across the IPs (?)
LLRF and controls
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L. Rossi - HL-LHC Design Study

20. WP4: Crab Cavity Design (2/2)
Main CC with beam topics
RF behavior for cavity quench or turbulent behavior
Tracking simulations for loss maps for fast failure modes (with WP 6 “Machine protection”)
Beam-beam simulations to investigate instabilities, noise issues and DA (with WP 2 “Beam physics”)
Impedance and growth rate estimates for specific HOMs to specify exact damping and feedback measures
Effect of non-zero dispersion and stable working points (with WP 2 “Beam physics”)
Crab consistent optics (with WP 2 “Beam physics”)
Potential participants:
CERN
Cockcroft Institute (U Lanc)
US-LARP
KEK
CEA
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L. Rossi - HL-LHC Design Study

21. WP5 – Collimation & Beam Losses Ralph Assmann
Topics:
Design of modified IR collimation system for the high luminosity upgrade.
IR loss-maps and support for background studies.
Impact of upgrades (e.g. crab cavities, off-momentum beta beat) on the collimation system.
Collimators, absorbers, … for the high luminosity upgrade.
Does not include the high intensity upgrade of the collimation system presently foreseen for 2014/15.
Participants
CERN
LARP/FNAL (N. Mokhov)
RHUL (G. Blair)
University Valencia (A. Faus-Golfe)
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L. Rossi - HL-LHC Design Study

22. WP6 – Machine Protection Jorg Wenninger
Content
Dump
Kicker
Failure scenario
Safety of new equipment
Interlock mangement
Partecipants:
CERN ?
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L. Rossi - HL-LHC Design Study

23. WP7 -Machine-Experiment Interface Austin Ball, Marzio Nessi
Content
Strategy, operation mode, beam types
L* and Absorber, aligment
Backgrounds (with WP5)
Early separation scheme
Integration
Interlocks
Partecipants
CERN
ATLAS & CMS ?
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L. Rossi - HL-LHC Design Study

24. L. Rossi - HL-LHC Design Study
Milestone
20 July : Meeting with our EU (US-J ?) partners
10 August: second draft
September : 2nd Meeting
September : visit Brux.?
1 October: near to final draft
15 October last meeting with approval of docum.
1 Nov : submission
Deadline is 15 November
Lucio + Oliver + all
Lucio
Lucio & Oliver + all
Lucio & JPK +…
Lucio & Oliver
All to meet it !!!
20 July 2010
L. Rossi - HL-LHC Design Study