vision from lhc to hl-lhc operation
DESCRIPTION
Vision from LHC to HL-LHC operation. Lucio Rossi For the HL-LHC project. LHC performance evolution ( guess !). 0.75 10 34 cm -2 s -1 50 ns bunch high pile up 40. 1.5 10 34 cm -2 s -1 25 ns bunch pile up 40. 1.7-2.2 10 34 cm -2 s -1 25 ns bunch pile up 60. - PowerPoint PPT PresentationTRANSCRIPT
The HiLumi LHC Design Study is included in the High Luminosity LHC project and is partly funded by the European Commission within the Framework Programme 7 Capacities Specific Programme, Grant Agreement 284404.
Vision from LHC to HL-LHC operation
Lucio RossiFor the HL-LHC project
2LRossi@R2E Workshop 14Oct2014
LHC performance evolution (guess!)
0.75 1034 cm-2s-1
50 ns bunch high pile up 40
1.5 1034 cm-2s-1
25 ns bunch pile up 40
1.7-2.2 1034 cm-2s-1
25 ns bunch pile up 60
Technical limits (experiments,
too) like :
50 25 ns
3LRossi@R2E Workshop 14Oct2014
Lumi evolution till 2035 (no learnimg…)
When learning curve is folded in (250f-1/y in 2028) need to plan eventually 300 fb-1/y, with 7-7.5 1034 cm-2s-1 . Design should also able to allow to 4000 fb-1, if needed.
5 1034 cm-2s-1 , levelling, 250 fb-1/y, 3000 fb-1
4LRossi@R2E Workshop 14Oct2014
High lumi insertions: higher, larger...
LHC triplet70 mm8 T11 kA
HL LHC triplet> 12 T150 mm15-17 kA
20 30 40 50 60 70 80distance to IP (m)
Q1 Q3Q2a Q2b
MC
BX
MC
BX
MC
BX
CP D1
Q: 140 T/mMCBX: 2.1 T 2.5/4.5 T mD1: 5.2 T 35 T m
4.0 4.0 4.0 4.06.8 6.8 6.71.2 1.2 2.2
SM
20 30 40 50 60 70 80distance to IP (m)
Q1 Q3Q2a
MC
BX
D1M
CB
X
MC
BX
Q2b
Q: 200 T/mMCBX: 3.3 T 1.5 T mD1: 1.8 T 26 T m
DFB
Longer Quads; Shorter D1 (thanks to SC)
ATLASCMS
ATLASCMS
E. Todesco
5Lucio Rossi@LMC184 9July2014
The HL-LHC Nb-T imagnet zoo…D1 (KEK) Nested orbit corrector (CIEMAT) HO correctors: superferric (INFN)
D2 (INFN) Q4 (CEA) D2 corrSee WP3 webpageE. Todesco et al.
6
Effect of the crab cavities
• RF crab cavity deflects head and tail in opposite direction so that collision is effectively “head on” and then luminosity is maximized• This are COMPACT CC, completely new
design! Must work synchronized (0.001) on each side of the IP!
Lucio Rossi@ICHEP2014
7Lucio Rossi@ICHEP2014
Latest cavity designs toward accelerator
RF Dipole: Waveguide orwaveguide-coax couplers
Double ¼-wave: Coaxial couplers withhook-type antenna
4-rod: Coaxial couplers with different antenna types
Coupler concepts
Concentrate on two designs
Present baseline: 3 cavity /cyomodule4 cavity/cryomod is under study for Crab Kissing TEST in SPS under preparation (A. MacPherson)
9
Low impedence collimators(LS2 & LS3)
Lucio Rossi@LMC184 9July2014
New material: MoGr
Reduce impedance by > 2)S. Redaelli et al.
Maybe already in LS2
10Lucio Rossi@LMC184 9July2014
LRBBW: an enabling tool that needs a definitive test
9.3
Test using an adapted collimatorTest is expensive!The final system cannot be an electric wire embedded in a jaw!Þ e-lens used as e-wireÞ However wee need > 200 Am!
NOT baseline (yet)
11
Controlling halo diffusion rate: hollow e-lens (synergy with LRBBCW)
Lucio Rossi@LMC184 9July2014
Promises of hollow e-lens:1. Control the halo dynamics without affecting the beam core;2. Control the time-profile of beam losses (avoid loss spikes);3. Control the steady halo population (crucial in case of CC fast failures).Remarks: - very convincing experimental experience in other machines!- full potential can be exploited if appropriate halo monitoring is available.
NOT baseline (yet)
12Lucio Rossi@LMC184 9July2014
Crystal collimation: a new paradigme in collimation (DS – partially – and primary
NOT baseline (yet)
13Lucio Rossi@LMC184 9July2014
Eliminating Technical BottlenecksCryogenics P4- P1 –P5
IT IT
ITIT
IT
ITIT
IT
RF
RF
New Plant 6 kW in P4 IN LS2
Two new 18 kW Plants in P1 and P5
14Lucio Rossi@LMC184 9July2014
New IR Cryo-scheme (sepration IR-Arc)
L. TavianR. Van WeelderenS. Claudet
15
Displacing EPC and DFB in the adjacent TDZ tunnel ( 500 m away) via SC linksIt si also a TEST!
DQR IP7
Q4Q5D3Q6DFBMDFBAQ11, Q10…Q7
IP 6
D4
4.5 K
8.75 m 1 m Warm magnets (PCs in UJ 76)
RR 73RR 73
Lucio Rossi@LMC184 9July2014
16Lucio Rossi@LMC184 9July2014
L = 20 m(252) 1 kA @ 25 K, LHC Link P7
Feb 2014: World record for HTS transport current (A. Ballarino)
17Lucio Rossi@LMC184 9July2014
ParameterNominal LHC
(design report)HL-LHC 25ns
(standard) HL-LHC 25 ns
(BCMS) HL-LHC 50ns
Beam energy in collision [TeV] 7 7 7 7Nb 1.15E+11 2.2E+11 2.2E11 3.5E+11nb 2808 27481 2604 1404
Number of collisions at IP1 and IP5 2808 2736 2592 1404Ntot 3.2E+14 6.0E+14 5.7E+14 4.9E+14beam current [A] 0.58 1.09 1.03 0.89x-ing angle [μrad] 285 590 590 590beam separation [σ] 9.4 12.5 12.5 11.4β* [m] 0.55 0.15 0.15 0.15εn [μm] 3.75 2.50 2.50 3εL [eVs] 2.50 2.50 2.50 2.50r.m.s. energy spread 1.13E-04 1.13E-04 1.13E-04 1.13E-04r.m.s. bunch length [m] 7.55E-02 7.55E-02 7.55E-02 7.55E-02IBS horizontal [h] 80 -> 106 18.5 18.5 17.2IBS longitudinal [h] 61 -> 60 20.4 20.4 16.1Piwinski angle 0.65 3.14 3.14 2.87Geometric loss factor R0 without crab-cavity 0.836 0.305 0.305 0.331Geometric loss factor R1 with crab-cavity (0.981) 0.829 0.829 0.838beam-beam / IP without Crab Cavity 3.1E-03 3.3E-03 3.3E-03 4.7E-03beam-beam / IP with Crab cavity 3.8E-03 1.1E-02 1.1E-02 1.4E-02Peak Luminosity without crab-cavity [cm-2 s-1] 1.00E+34 7.18E+34 6.80E+34 8.44E+34Virtual Luminosity with crab-cavity: Lpeak*R1/R0 [cm -2 s-1] (1.18E+34) 19.54E+34 18.52E+34 21.38E+34
Events / crossing without levelling w/o crab-cavity 27 198 198 454Levelled Luminosity [cm-2 s-1] - 5.00E+34 5.00E34 2.50E+34Events / crossing (with levelling and crab-cavities for HL-LHC) 27 138 146 135Peak line density of pile up event [evt/mm] (max over stable beam) 0.21 1.25 1.31 1.20Levelling time [h] (assuming no emittance growth) - 8.3 7.6 18.0
Baseline Parameters (last PLC)
ATS required
Colli
sion
val
ues
18Lucio Rossi@LMC184 9July2014
The Achromatic Telescopic Squeezing (ATS) scheme Small b* is limited by aperture but not only: optics matching & flexibility (round and flat optics), chromatic effects (not only Q’), spurious dispersion from X-angle,..
A novel optics scheme was developed to reach un-precedent b* w/o chromatic limit based on a kind of generalized squeeze involving 50% of the ring
ATS is not an option is critical for the upgrade; implementation in Run II or Run III is beneficial!
b*= 40 cm b*= 10 cm
The new IR is sort of 8 km long !
(S. Fartoukh)
Proof of principle demonstrated in the LHC down to a b* of 10-15 cm at IP1 and IP5
19Lucio Rossi@LMC184 9July2014
The ``crab-kissing’’ (CK) scheme (2/5)
0.2 0.1 0.1 0.2
0.2
0.4
0.6
0.8
1.0
1.2
[mm-1]
z [m] w.r.t. IP
HL-LHC w/o CK scheme: Plan A (solid) and Plan B(dotted)- 12.5 MV crabs in X-plane, round optics (15/15 cm), sz =7.5 cm (Plan A)- or bb wire, flat optics (50/10 cm), sz =10 cm (Plan B)
“HL-LHC+” with CK scheme and Gaussian bunch profile ..adding crab-cavities to Plan B in X and || planes (6 MV+7 MV)
“HL-LHC++” with CK scheme and rectangular bunch profile ... adding a new 800 MHz RF system (still keeping sz =10 cm)
A net gain by a factor 2 at each step.... at nearly constant integrated performance
(S. Fartoukh)@ECFA HL –LHCExper. Workshop, Aix-les-Bains7October 2013
20Lucio Rossi@LMC184 9July2014
Operation & Intensity• Levelling cycle
• Beam intensity limitation(s)• To be assessed in next LHC run• TDIS in LS2 (don’t like too small emittance beams!)• Heating of kickers (MKI): new high Tc ferrite and
coating for e-clouds (prototype installed in LS2).
21Lucio Rossi@LMC184 9July2014
Efficiency for Ldt• All our assumptions are based on forecast for
the operation cycle:
𝜼=𝑳𝒕𝒂𝒓𝒈𝒆𝒕
𝑳𝒇𝒊𝒍𝒍
𝑻 𝒂𝒓𝒐𝒖𝒏𝒅−𝒎𝒊𝒏+𝑻 𝒇𝒊𝒍𝒍
𝑻 𝒔𝒑𝒕×𝟏𝟎𝟎
50%
High reliability and availbility are key goalsR. DeMaria, RLIUP
Integral luminosity: the final goal of HL_LHC• The total number of particles created at collider (e.g. total number of
Higgs bosons) is proportional to the Integrated Luminosity (expressed in fb-1):
• In the past, the most efficient way of increasing was by increasing . This is why accelerator people usually refer to .
• There are many workshops and conferences around the world discussing how to increase …..
• HL-LHC is a game changer: for the first time, is limited (due to pile-up and other considerations), to a certain extend...
• The only free parameters is the integral: how long can HL-LHC sustain operation a?
• Directly related to the availabilty of HL-LHC – this is the motivation for this workshop.
M. Brugger
Global Workshop ObjectivesUnderstand availability limitations due to radiation effects (SEE, TID, DD) as well as other effects onto accelerator equipment and quantify the required equipment performance to reach the luminosity goals Run 2, Run 3, HL-LHC.
Identify what is required (tools, facilities, expertise) to quantify and mitigate radiation effects on equipment.
Identify appropriate mitigation measures: radiation tolerant developments (tunnel electronics, PC), displacement of sensitive equipment (superconducting links etc.) and other aspects.
Identify the long-term requirements for electronic systems.
Address IR3-IR7 life time issues linked to radiation and equipment maintenance planning.
Understand how development of electronics for radiation environment is addressed in the LHC experiments.
Global Workshop ObjectivesUnderstand availability limitations due to radiation effects (SEE, TID, DD) as well as other effects onto accelerator equipment and quantify the required equipment performance to reach the luminosity goals Run 2, Run 3, HL-LHC.
Identify what is required (tools, facilities, expertise) to quantify and mitigate radiation effects on equipment.
Identify appropriate mitigation measures: radiation tolerant developments (tunnel electronics, PC), displacement of sensitive equipment (superconducting links etc.) and other aspects.
Identify the long-term requirements for electronic systems.
Address IR3-IR7 life time issues linked to radiation and equipment maintenance planning.
Understand how development of electronics for radiation environment is addressed in the LHC experiments.
Aiming for high availability
Radiation effectsSingle Event Errors (SEEs)
LS1 focus on mitigationFrom MITIGATION to PREVENTION
Cumulative (long-term) damage (TID, DD)so far not encountered at LHC (experience from injectors!)
Equipment failures (focus on electronics components)experience, development needs, options
Components reaching the end of life with and without radiation
Workshop Goals
25
Concerns for what to do next, but also in view of 22 years of LHC: we need R&D NOW!
What needs to be doneup to LS2/LS3 and for HL-LHC
Radiation damage and intervention concerns in IR3/7Design/test choices and synergies to be exploitedRequirements to reach the HL-LHC target
AvailabilityExpertise & FacilitiesDevelopments & Qualification Needs
Workshop Goals
26
In view of the 4 Workshop Sessions
Session-1: Fundamentals of R2E and Availability Radiation Monitoring & Test Facilities:
improve/operate
R2E Expertise (LHC, Injectors, Experiments): keep & develop
Availability: fault tracking, impact analysis:improve/adopt
Needs and Goals
27
In view of the 4 Workshop Sessions
Session-2: Concerned Equipment: up to LS2/LS3/HL-LHC Development needs and R2E requirements:
R2E structure?
Maintenance and lifetime (with & w/o. rad.): What is known and what needs to be?
How to improve availability:What can and has to be done?
Needs and Goals
28
In view of the 4 Workshop Sessions
Session-3: IR3/7 Damage/Maintenance IssuesFailure risks due to radiation/environment:
is there any show-stopper?
Needs: monitoring, handling, testing: what is ok and what needs to be improved?
Maintenance, life-time & mitigation: what is the equipment requirement/strategy?
Needs and Goals
29
In view of the 4 Workshop Sessions
Session-4: Long-term strategyMitigation/Prevention strategy & needs:
are we on the right track?
SCL & rad-tol PC options/needs/roadmap: what is the (combined) best strategy?
Required developments & synergies: what are and can be common grounds?
Needs and Goals
30
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SC links removal of EPCs, DFBs from tunnel to surface (or new gallery?)
Lucio Rossi@LMC184 9July2014
2150 kA
1 pair 700 m 50 kA – LS24 pairs 300 m 150 kA (MS)– LS3 4 pairs 300 m 150 kA (IR) – LS3 tens of 6-18 kA CLs pairs in HTS
Past Present Future
33
Run 1:
HL-LHC:
HL-LHC:
160 days
25 fb-1
200 days
210 fb-1
260 fb-1
HL-LHC:200 days + 20% availability 300 fb-1
R2E LHC Long-TermR2E SEE Failure Analysis
~250 hDowntime
2008-2011Analyze and mitigate all safety relevant cases and limit global impact
2011-2012Focus on long downtimes and shielding
LS1 (2013/2014)Final relocation and shielding
LS1-LS2 (2015-2018)Tunnel equipment and power converters
-> LS3-HL-LHCTunnel Equipment (Injectors + LHC) + RRs
~400 hDowntime
LS1 – LS2 Aiming for
<0.5 dumps / fb-1
~12
dum
ps /
fb-1
~3 d
umps
/ fb
-1
HL-LHC: < 0.1 dumps / fb-1
34
Relocation& Shielding
Equipment Upgrades