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Title: LHC status, commissioning,


1
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2
LHC status, commissioning, upgrade
Frank Zimmermann, KEK seminar, 5 January 2007
3
Large Hadron Collider (LHC)
proton-proton collider next energy-frontier
discovery machine c.m. energy 14 TeV (7x
Tevatron) design luminosity 1034 cm-2s-1 (100x
Tevatron) 450-GeV engineering run in fall 2007
first 7-TeV physics run In 2008
nominal LHC already a very challenging machine!
4
Mission No. 1 Finding the Higgs Boson
Standard Model origin of mass explained via a
mechanism named after the British physicist Peter
Higgs. Predicted new particle the Higgs boson.

LHC energy suffices to produce the Higgs boson
via .
S.F. King
5
LHC status
  • s.c. magnet production installation
  • other hardware installation
  • LHC milestones
  • some recent trouble
  • machine protection collimation
  • advanced beam instrumentation

6
(No Transcript)
7
Magnet production for the LHC is complete!
27 November saw the end of production of the
machine's main magnets. Some 1232 main dipole
and 392 main quadrupole magnets have been
manufactured in an unprecedented collaboration
effort between CERN and European industry.
8
progress of magnet installation
Lyn Evans LHCMAC 7.12.2006
9
2007 hardware commissioning
Roberto Saban, LHC MAC 08.12.2006
10
  • Also in November 2006
  • Installation of cryogenic distribution line
    complete
  • 100 of power converters installed, 2/3 tested
  • One LHC sector completely interconnected
  • CMS lowered two detector sections into cavern
  • ATLAS toroid magnet was ramped up to maximum
    current

11
LHC milestones
?
Last magnet delivered November 2006
Last magnet tested January 2007
Last magnet installed March 2007
Machine closed August 2007
First collisions 450 GeV November 2007
First Collisions 7 TeV June 2008
Lyn Evans, LHC MAC 07.12.2006
12
  • Some recent trouble heat exchanger tube in one
    inner triplet failed at 9 bar differential
    pressure (much below the maximum pressure of 27.5
    bar) but arc was OK!
  • Appears to be generic problem for all inner
    triplets (design testing mistake at FNAL)
  • In-situ repair likely to be possible
  • Impact on schedule uncertain at the moment

Lyn Evans, LHCMAC 7.12.2006
13
The LHC Challenge
Energy density at collimators(nominal 7 TeV conditions) Stored energy
State-of-the-art in SC colli-ders (TEVATRON, HERA, ) 1 MJ/mm2 2 MJ
Phase 1 LHC Collimation 400 MJ/mm2 150 MJ
Nominal 1 GJ/mm2 360 MJ
Ultimate upgrade scenarios 4 GJ/mm2 1.5 GJ

Limit (damage/quench) 50 kJ/mm2 30 mJ/cm3
2x10-10-2x10-11
R.W. Assmann, LHCMAC 8.12.2006
10-4-10-5
14
LHC collimation system
presently problems with technical quality control
at CERCA (French nuclear industry)
Phase 1
Momentum Cleaning
Betatron Cleaning
minimal system for 450 GeV run 28
collimators full system 91 collimators
(delayed to 2008)
15
Intensity Limitation 1 Collimator Impedance
E. Metralet al
? Limitation at about 40 of nominal intensity
(nominal b, full octupoles)
R.W. Assmann, LHCMAC 8.12.2006
Important Collimator impedance was measured in
the SPS with LHC prototype collimator.
16
Intensity Limitation 2 Single-Diffractive
Scattering in Primary Collimators
Cross-section single-diffractive scattering
Comparison FLUKA STRUCT COLLTRACK/K2
R.W. Assmann, LHCMAC 8.12.2006
  • Single-diffractive scattering in primary betatron
    collimators large energy offset and small
    betatronic kick.
  • ? Betatron collimators generate off-momentum
    halo.
  • Most of newly off-momentum protons are lost in
    first place with high dispersion downstream
    dispersion suppressor.

? Limitation at about 30-40 of nominal
intensity due to quenches in IR7
17
SLAC Phase-2 Collimator Design and Prototyping
Rotatable LHC Collimator
R.W. Assmann, LHCMAC 8.12.2006
Strong SLAC commitment and effort Theoretical
studies, mechanical design, prototyping. One full
time mechanical engineer. Looking for SLAC
post-doc on LHC collimation!
Design with 2 rotating Cu jaws
Phase 2 should allow reaching nominal intensity
and beyond
First prototype with helical cooling
circuit (SLAC workshop)
18
Phase 2 Schedule (CERN Whitepaper)
  • 2005 Start of phase 2 LHC collimator RD at SLAC
    (LARP) with CERN support
  • Completion of three phase 2 prototypes
  • 2009 Installation of prototypes in LHC beam
    tests at 7 TeV.
  • Installation of 30 phase-2 collimators during the
    2010/11 shutdown.
  • 2011 Commissioning of phase 2 collimation
    system.LHC ready for nominal and higher
    intensities.

R.W. Assmann, LHCMAC 8.12.2006
19
  • Instrumentation Tune, Coupling and Chromaticity
    Measurement
  • Combination of BBQ and PLL very powerful
  • RHIC demonstrated combined tune coupling
    feedback
  • Efforts in 2007 on adding chromaticity feedback

R. Jones, LHCMAC, 7.12.2006
Baseband Q measurement (BBQ)
Marek Gasior
Coupling correction using PLL tune tracker
tested at RHIC (2006)
BNLCERN
Continuous FFT and PLL Implemented in FPGA
DQ1e-6 achieved with 1 s integration
20
LHC Mission No 2 Finding SUSY
S.F. King
21
LHC commissioning plan
  • overall strategy
  • parameter evolution
  • commissioning sequence 2007 2008
  • 450-GeV engineering run in 2007
  • 2008 draft schedule
  • commissioning organization
  • accelerator systems
  • slots for participants from US-LARP KEK

22
Overall commissioning strategy for protons (estd.
2005)
Stage I
II
III
IV
Hardware commissioning Machine checkout Beam commissioning 43 bunch operation 75ns ops 25ns ops I Install Phase II and MKB 25ns ops II
No beam
Beam
  • Pilot physics run
  • First collisions
  • 43 bunches, no crossing angle, no squeeze,
    moderate intensities
  • Push performance
  • Performance limit 1032 cm-2 s-1 (event pileup)
  • 75ns operation
  • Establish multi-bunch operation, moderate
    intensities
  • Relaxed machine parameters (squeeze and crossing
    angle)
  • Push squeeze and crossing angle
  • Performance limit 1033 cm-2 s-1 (event pileup)
  • 25ns operation I
  • Nominal crossing angle
  • Push squeeze
  • Increase intensity to 50 nominal
  • Performance limit 2 1033 cm-2 s-1
  • 25ns operation II
  • Push towards nominal performance

R. Bailey, LHCMAC 7.12.2006
23
Evolution of beam levels and luminosity stages I
II III
R. Bailey, LHCMAC 7.12.2006
43/156 bunch operation 75ns operation 25ns operation I
45 of nominal I
25 of nominal I
5 of nominal I
24
LHC Commissioning Sequence 2007 and 2008
  • Machine is closed
  • ?
  • Minimum hardware commissioning
  • ?
  • Nov/Dec 2007 Beam operation with collisions at
    450 GeV
  • ?
  • Full hardware commissioning and installation of
    some delayed equipment for 7 TeV (e.g. some
    collimators)
  • ?
  • LHC commissioning for 7 TeV physics
  • ?
  • LHC High Energy Operation

R. Bailey, LHCMAC 7.12.2006
25
Engineering run in 2007
R. Bailey, LHCMAC 7.12.2006
0
Installation Hardware Commissioning Hardware Commissioning 450GeV Engineering Run 450GeV
Machine checkout 450GeV Beam commissioning 450GeV Collisions 450GeV Ramp commissioning
  • Aims
  • Commission essential safety systems
  • Commission essential beam instrumentation
  • Commission essential hardware systems
  • Perform beam based measurements to check
  • Polarities
  • Aperture
  • Field characteristics
  • Establish stable two beam operations
  • Provide collisions
  • Interleave with further machine development, in
    particular, the ramp

Should provide a firm platform for eventual
commissioning to 7 TeV and provide lead time for
problem resolution.
26
450GeV run - Machine Configuration
  • Crossing angles off
  • 1, 12, 43, 156 bunches
  • Separation bumps on
  • 2 beam operation
  • Optics
  • ß 11m in IR 1 5
  • ß 10m in IR 2 8
  • Transverse beam sizes
  • 290 µm at 1 and 5
  • 277 µm at 2 and 8
  • Shift bunches for LHCb
  • 4 out of 43 bunches
  • 16 bunches out of 156
  • Nominal bunch length 11.24 cm (8 MV)

LHC
25 ns
ISR
75 ns
TevatronHERA
156 b
43 b
SNS
LEP2
Working area 2007 run
R. Bailey, LHCMAC 7.12.2006
27
Overall time needed for 450-GeV commissioning
Phase Beam time days Beam
1 First turn 4 1 x Pilot
2 Establish circulating beam 3 1 x Pilot
3 450 GeV initial 3 1 x Pilot
4a 450 GeV - consolidation 1-2 1 x Pilot
4b 450 GeV system commissioning 2-3 1 x Pilot
5a 2 beam operations 1 2 x Pilot
5b Collisions 1-2 2 x Pilot ?
16 days
Given an operational efficiency of 60, this
gives an elapsed time of about 26 days.
Some opportunities for parallel development and
parasitic studies
R. Bailey, LHCMAC 7.12.2006
28
2008 draft schedule
  • 3 month shutdown (no beam)
  • 4 weeks checkout (no beam)
  • 8 weeks beam commissioning
  • 26 weeks physics run (protons)
  • 20 days physics
  • 4 days MD
  • 3 days technical stop

LHC Hardware Commissioning to 7TeV
LHC Machine Checkout
LHC Beam Commissioning
LHC Physics run
LHC Physics run
R. Bailey, LHCMAC 7.12.2006
29
LHC commissioning organisation (LTC Dec 14th 2005)
R.Bailey
M.Lamont
(O.Bruning)
(P.Collier)
G.Arduini
R.Assmann
M.Giovannozzi
S.Fartoukh
J.Uythoven
J.Wenninger
F.Zimmermann
Accelerator system






Accelerator system






Accelerator system






Accelerator system






S.Redaelli 01.06
M.Gruwe 01.06
EIC3 07.06
EIC4 07.06
EIC5 01.07
EIC6 01.07
EIC7 01.07
Accelerator system
Activity 1
Activity 2



Activity n
M.Albert
G.Crockford
R.Giachino
G.H.Hemelsoet
D.Jacquet
L.Normann
F.Pirotte
R.Suykerbuyk
E.Veyrunes
here KEK experts could contribute
R. Bailey, LHCCWG, March 2006
30
Accelerator systems Contact
Technical Services TI operations P.Sollander
Technical Services Controls H.Schmickler
Technical Services Electrical supply F.Rodriguez Mateos
Technical Services Cooling and ventilation J.Inigo-Golfin
Technical Services Access safety systems T.Pettersson
Hardware Commissioning Cryogenics L.Serio
Hardware Commissioning Main Ring Magnets Performance A.Siemko
Hardware Commissioning Insertion Magnets Performance R.Ostojic
Hardware Commissioning PIC B.Puccio
Hardware Commissioning QPS K.H.Mess
Hardware Commissioning Power converters F.Bordry
Beam Commissioning Vacuum N.Hilleret
Beam Commissioning Magnetic Model J.P.Koutchouk
Beam Commissioning Beam Machine Protection Systems R.Schmidt
Beam Commissioning Radiation Protection D.Forkel-Wirth
Beam Commissioning Radiation monitoring T.Wijnands
Beam Commissioning Beam Transfer V.Mertens
Beam Commissioning RF T.Linnecar
Beam Commissioning Beam Instrumentation R.Jones
Beam Commissioning Collimation R.Assmann
Beam Commissioning High level controls M.Lamont
Beam Commissioning Operations R.Bailey
Beam Commissioning Accelerator physics O.Bruning
Beam Commissioning Experimental Conditions H.Burkhardt
31
Vacuum P.Strubin, N.Hilleret Vacuum P.Strubin, N.Hilleret Vacuum P.Strubin, N.Hilleret Vacuum P.Strubin, N.Hilleret
Activity AT/VAC Other CERN LARP/KEK
Insulating vacuum Beam vacuum (ring) Beam vacuum (expts) Electron cloud V.Baglin P.Cruikshank M.Jimenez E.Mahner C.Rathjen A.Rossi G.Arduini (AP) F.Zimmermann (AP) M.Furman (LBNL) Toohig fellow
Beam Transfer V.Mertens Beam Transfer V.Mertens Beam Transfer V.Mertens Beam Transfer V.Mertens
Activity AB/BT Other CERN LARP/KEK
SPS extraction Transfer lines Injection region First turn Protection devices Beam dump J.Uythoven B.Goddard V.Kain (OP) M.Lamont (OP) J.Wenninger (OP) T.Risselada (AP) H.Burkhardt (AP) W.Herr (AP) M.Syphers (FNAL) E.Harms (FNAL)
MKQA J.Uythoven S.Fartoukh (AP) F.Schmidt (AP)
AC dipole L.Ducimetiere J.Serrano (CO) F.Schmidt (AP)
RF T.Linnecar, E.Chapochnikova RF T.Linnecar, E.Chapochnikova RF T.Linnecar, E.Chapochnikova RF T.Linnecar, E.Chapochnikova
Activity AB/RF Other CERN LARP/KEK
Machine synchronisation Capture 450GeV plateau Acceleration Storage Transverse damping P.Baudrenghien T.Bohl O.Brunner A.Butterworth E.Ciapala W.Hofle J.Tuckmantel
Transverse feedback C.Y.Tan (FNAL)
32
Beam Instrumentation R.Garoby, R.Jones Beam Instrumentation R.Garoby, R.Jones Beam Instrumentation R.Garoby, R.Jones Beam Instrumentation R.Garoby, R.Jones
Activity AB/BDI Other CERN LARP/KEK
Screens E.Bravin A.Guerrero H.Burkhardt (AP) G.Arduini (AP)
BCT P.Odier D.Belohrad M.Ludwig H.Burkhardt (AP) J.Jowett (AP)
BPM and orbit R.Jones L.Jensen J.Wenninger (OP) R.Steinhagen (OP) W.Herr (AP) I.Papaphilippou (AP)
BLM B.Dehning E.Holzer S.Jackson L.Ponce (OP) R.Assmann (AP) H.Burkhardt (AP) B.Jeanneret (AP) S.Gilardoni (AP)
PLL for Q, Q, C R.Jones M.Gasior P.Karlsson S.Fartoukh (AP) O.Berrig (AP) J.Wenninger (OP) C.Y.Tan (FNAL) P.Cameron (BNL)
Profile monitors S.Hutchins J.Koopman A.Guerrero H.Burkhardt (AP) S.Gilardoni (AP) M.Giovannozzi (AP) A.Jansson (FNAL)
Schottky monitors F.Caspers (AB/RF) R.Jones S.Bart-Pedersen E.Metral (AP) C.Carli (AP) F.Zimmermann (AP) R.Pasquinelli (FNAL) A.Jansson (FNAL)
Luminosity monitors E.Bravin S.Bart-Pedersen R.Assmann (AP) F.Zimmermann (AP) Toohig fellow
33
Accelerator Physics O.Bruning Accelerator Physics O.Bruning Accelerator Physics O.Bruning Accelerator Physics O.Bruning
Activity AB/ABP Other CERN LARP/KEK
Optics T.Risselada O.Bruning S.Fartoukh M.Giovannozzi W.Herr Y.Papaphilippou V.Ranjbar (FNAL) M.Syphers (FNAL) A.Jansson (FNAL)
Beta beating R.Tomas Garcia M.Giovannozzi J.Wenninger (OP) R.Calaga (BNL) A. Warner (FNAL)
MADX online model F.Schmidt M.Lamont (OP) Akio Morita (KEK)
Aperture in arcs Y.Papaphilippou B.Jeanneret W.Herr, F.Schmidt F.Zimmermann S.Redaelli (OP) E.Harms (FNAL) Toohig fellow
Aperture in IRs Y.Papaphilippou W.Herr
Impedance E.Metral F.Ruggiero F.Zimmermann Toohig fellow
Lattice correctors F.Schmidt M.Giovannozzi S.Fartoukh Y.Papaphilippou M.Martens (FNAL) M.Syphers (FNAL) V.Ranjbar (FNAL)
Triplet correctors F.Schmidt M.Giovannozzi S.Fartoukh T.Sen (FNAL) M.Syphers (FNAL)
Lifetimes J.Jowett F.Zimmermann X.Zhang (FNAL)
Separation / Crossing W.Herr F.Zimmermann Y.Papaphilippou
Collisions and beam-beam W.Herr R.Assmann R.Moore (FNAL) J.Annala (FNAL) E.Harms (FNAL)
Luminosity H.Burkhardt W.Herr R.Assmann R.Moore (FNAL) J.Annala (FNAL) E.Harms (FNAL)
34
Operations R.Bailey Operations R.Bailey Operations R.Bailey Operations R.Bailey
Activity AB/OP Other CERN LARP/KEK
Beam in the injectors M.Gruwe G.Arduini D.Capista (FNAL) A.Drees for ions (BNL)
Quench recovery
Post mortem recovery
Filling efficiency EIC 2 M.Martens (FNAL)
450GeV plateau EIC 3
Snapback EIC 4 A.Jansson (FNAL)
Ramp EIC 5 A.Jansson (FNAL)
Squeeze EIC 6 A.Jansson (FNAL)
Physics EIC 7
High Level Controls M.Lamont High Level Controls M.Lamont High Level Controls M.Lamont High Level Controls M.Lamont
Activity AB/OPCO Other CERN LARP/KEK
Closed orbit J.Wenninger R.Steinhagen (BI)
Real time FB R.Steinhagen (BI) M.Martens (FNAL)
Post Mortem A.Raimondo
Sequencer R.Alemany D.Still (FNAL)
Role based access G.Gysin (FNAL)
Shot data analysis G.H.Hemelsoet, E.Veyrunes E.McCrory (FNAL)
General J.Slaughter (FNAL) R.Moore(FNAL)
35
Still more missions of LHC
H. Murayama, Nanobeam 2005
36
LHC upgrade
  • motivation
  • limitations remedies
  • electron-cloud countermeasures
  • LUMI06 workshop
  • example IR layouts
  • parameter sets luminosity evolution
  • injector upgrade
  • energy upgrade
  • upgrade schedule

37
time scale of LHC upgrade
radiation damage limit 700 fb-1
Jim Strait, 2003
time to halve error
integrated L
CMS inner layer
L at end of year
ultimate luminosity
design luminosity
(1) life expectancy of LHC IR quadrupole magnets
is estimated to be lt10 years due to high
radiation doses (2) CMS (ATLAS?) inner detector
layers need to be replaced after 4-5 years (3)
statistical error halving time exceeds 5 years by
2011-2012 ? it is reasonable to plan a machine
luminosity upgrade based on new low-b IR magnets
around 2014-2015
38
limitations
  • triplet aperture, l crossing angle limit min.
    b
  • long-range beam-beam effect causes dynamic
    aperture at 6s for nominal LHC
  • e- cloud gives rise to heat-load in s.c. magnets,
    CB and SB instabilities, and poor beam lifetime
    (all seen in the SPS)
  • geometric luminosity loss due to crossing angle,
    20 for nominal LHC
  • intensity limits from collimation
  • number of detector pile-up events per crossing
  • (RHIC p-p lt1, Tevatron Run-II 2, nominal LHC
    20)

39
remedies
  • reduce b by stronger larger-aperture low-beta
    quadrupoles based on Nb3Sn, pushed NbTi, or
    hybrid scheme, and closer to the IP
  • detector integrated slim s.c. quadrupole doublet
    (effective decrease of l)
  • detector integrated slim early-separation dipole
  • long-range beam-beam compensators
  • small-angle crab cavities
  • adaptation of filling pattern and beam parameters
  • e-cloud cures for LHC, SPS, and PS(2)

40
joint CARE-HHH EUROTeV mini-workshop on
Electron Cloud Clearing ECL2, CERN, 1-2 March
2007 low and high resistance structures other
cures
http//care-hhh.web.cern.ch/CARE-HHH/ECL2
Prototype chamber with double-layer enamel
coating forming two clearing strips from German
industry. Concept F. Caspers Realization F.J.
Behler, Eisenwerke Dueker,D-63846 Laufach.
41
APD workshop LUMI 06 (70 participants) Towards
a Roadmap for the Upgrade of the LHC and GSI
Accelerator Complex IFIC, Valencia (Spain),
16-20 October 2006? strong synergy with US-LARP
mini collaboration meeting 25-27 Oct. 2006
  • IR scheme, beam parameters, injector upgrade

42
LUMI06 Conclusions
  • IR upgrade beam parameters
  • quadrupole 1st preferred over dipole 1st
  • pushed NbTi or Nb3Sn still pursued, or hybrid
    solution - new
  • slim magnets inside detector (D0 and Q0) new
  • wire compensation almost established, electron
    lens new
  • crab cavities large angle rejected small-angle
    new
  • 12.5 ns strongly deprecated
  • e-cloud/pile-up compromise 25-ns w b10
    cm, or 50-ns spacing long bunches new
  • injector upgrade
  • linac4/SPL n.c. PS2 endorsed
  • SPS enhancements - new
  • s.c. PS2 challenged e.g., e-cloud could be
    serious problem for injectors - new

43
Example IR Layouts
D0 dipole deep inside detector (e.g., 3 m from
IP)
triplet magnets
D0 dipole
small-angle crab cavity
less LR collisions. no geometric lumi. loss
not so short bunches near head-on collision
Q0 doublet deep inside detector (7.5 or 13 m
from IP)
triplet magnets
wire compensator
Q0 doublet
triplet quads much easier, less Q, could be
combined with D0
short bunches minimum crossing angle wire
44
Are there slots for a D0 in ATLAS?
  • We cannot put the D0 in the inner detector which
    excludes the FES for 25 ns.
  • BUT there are potential slots starting at 3.5 m
    and 6.8 m (ATLAS) that are the starting points
    for our study of a PES.

G. Sterbini, J.-P. Koutchouk, LUMI06
45
Strategy for D0 implementation
  • We can consider the first two ATLAS slots
  • Slot1 starting at 3.49 m from IP with a total
    length of 1.09 m
  • Slot2 starting at 6.80 m from IP with a total
    length of 1.86 m
  • We can obtain the 8 Tm splitting the dipole into
    two
  • a 4 T D0a in Slot1 (it should be transparent)
  • a 4 T D0b in Slot2 (it should be massive)

G. Sterbini, J.-P. Koutchouk, LUMI06
46
Where would we put the D0 in ATLAS?
G. Sterbini, J.-P. Koutchouk, LUMI06
47
The same strategy in CMS
G. Sterbini, J.-P. Koutchouk, LUMI06
48
plus can use crab cavities event pile up
tolerable
bunch structures
more shorter bunches
nominal ultimate LHC
concerns e-cloud, LRBB, impedance heating
12.5 ns
25 ns
longer (fewer) bunches
50 ns
25 ns
bigger shorter OR more focused bunches
concerns event pile up impedance
plus no e-cloud? less current
concerns impedance heating, LR
compensation, aberrations
plus limited e-cloud limited pile up
transitions by bunch merging or splitting new rf
systems required for some cases
49
parameter symbol nominal ultimate 12.5 ns spac., short 75 ns spacing, long
transverse emittance e mm 3.75 3.75 3.75 3.75
protons per bunch Nb 1011 1.15 1.7 1.7 6
bunch spacing Dt ns 25 25 12.5 75
beam current I A 0.58 0.86 1.72 1
longitudinal profile Gauss Gauss Gauss flat
rms bunch length sz cm 7.55 7.55 3.78 14.4
beta at IP15 b m 0.55 0.5 0.25 0.25
full crossing angle qc murad 285 315 445 430
Piwinski parameter qcsz/(2sx) 0.64 0.75 0.75 2.8
peak luminosity L 1034 cm-2s-1 1 2.3 9.2 8.9
events per crossing 19 44 88 510
initial lumi lifetime tL h 22 14 7.2 4.5
effective luminosity (Tturnaround10 h) Leff 1034 cm-2s-1 0.46 0.91 2.7 2.1
effective luminosity (Tturnaround10 h) Trun,opt h 21.2 17.0 12.0 9.4
effective luminosity (Tturnaround5 h) Leff 1034 cm-2s-1 0.56 1.15 3.6 2.9
effective luminosity (Tturnaround5 h) Trun,opt h 15.0 12.0 8.5 6.6
e-c heat SEY1.4(1.3) P W/m 1.07 (0.44) 1.04 (0.6) 13.34 (7.85) 0.26
SR heat load 4.6-20 K PSR W/m 0.17 0.25 0.5 0.29
image current heat PIC W/m 0.15 0.33 1.87 0.96
gas-s. 100 h (10 h) tb Pgas W/m 0.04 (0.38) 0.06 (0.6) 0.113 (1.13) 0.07 (0.7)
comment partial wire c. partial wire c.
high pile up not accept-ed by exper-iments
LUMI05 parameters
old upgrade parameters
heat load exceeds local cooling capacity
50
parameter symbol ultimate 25 ns, smaller b 25 ns, large e 50 ns, long
transverse emittance e mm 3.75 3.75 7.5 3.75
protons per bunch Nb 1011 1.7 1.7 3.4 4.9
bunch spacing Dt ns 25 25 25 50
beam current I A 0.86 0.86 1.72 1.22
longitudinal profile Gauss Gauss Gauss Flat
rms bunch length sz cm 7.55 7.55 3.78 11.8
beta at IP15 b m 0.5 0.08 0.25 0.25
full crossing angle qc murad 315 0 630 381
Piwinski parameter qcsz/(2sx) 0.75 0 2.75 2.0
peak luminosity L 1034 cm-2s-1 2.3 18.1 9.2 10.7
events per crossing 44 343 176 407
initial lumi lifetime tL h 14 1.8 7.2 4.5
effective luminosity (Tturnaround10 h) Leff 1034 cm-2s-1 0.91 2.6 2.7 2.5
effective luminosity (Tturnaround10 h) Trun,opt h 17.0 6.1 12.0 9.4
effective luminosity (Tturnaround5 h) Leff 1034 cm-2s-1 1.15 3.8 3.7 3.5
effective luminosity (Tturnaround5 h) Trun,opt h 12.0 4.3 8.5 6.7
e-c heat SEY1.4(1.3) P W/m 1.04 (0.59) 1.04 (0.59) 2.56 (2.1) 0.36 (0.1)
SR heat load 4.6-20 K PSR W/m 0.25 0.25 0.5 0.36
image current heat PIC W/m 0.33 0.33 3.70 0.78
gas-s. 100 h (10 h) tb Pgas W/m 0.06 (0.56) 0.06 (0.56) 0.11 (1.13) 0.09 (0.9)
comment D0 crab wire comp. wire comp.
LUMI06 parameters
new upgrade parameters
51
for operation at the beam-beam limit luminosity
equation can be rewritten as
?? 50 ns
? 50 ns
?? 25 ns
? 50 ns
52
two new scenarios emerged
  • stay with ultimate LHC beam, squeeze b to 10
    cm, add early-separation dipoles in detectors
    crab cavities (fPiwinski 0)
  • ? new hardware inside detectors, possible
    interference
  • double bunch spacing, use longer more intense
    bunches with fPiwinski 2, but keep b25 cm, do
    not add any elements inside detector, LR-BB
    compensator may be needed
  • ? new operating regime for hadron collider

53
25 ns spacing
50 ns spacing
54
50 ns spacing
25 ns spacing
55
injector upgrade - motivations
raising beam intensity (higher bunch charge,
shorter spacing etc.), for limited geometric
aperture, LeN, may be essential for
alternative scheme reduction of dynamic effects
(persistent currents, snapback, etc.) ?
improvement of turn-around time by factor 2,
effective luminosity by 50 benefit to other
CERN programmes (n physics, b beams,)
56
LHC injector upgrade
  • SPS
  • extraction energy 450 GeV ?1 TeV
  • PS2 or PS2
  • extraction energy 26 GeV ? 50 or 75 GeV
  • LHC
  • injection energy 450 GeV ? 1 TeV
  • Super ISR is alternative to Super PS
  • Superferric ring pipetron in LHC tunnel is
  • alternative to Super SPS issue detector bypass

57
Upgraded CERN Complex
fast cycling dipoles for Super-LHC injectors
Super-LHC
Super-SPS
Super-Transferlines
PS2
PS2?
58
ultimate LHC upgrade higher beam energy
  • 7 TeV?14 (21) TeV?
  • RD on stronger magnets

59
Six institutes CCLRC/RAL (UK), CEA/DSM/DAPNIA
(France), CERN/AT (International),
INFN/Milano-LASA INFN/Genova (Italy), Twente
University (the Netherlands), Wroclaw University
(Poland). Three s.c. wire manufacturers (also
contributing financially) Alstom/MSA (France),
ShapeMetal Innovation (the Netherlands),
Vacuumschmelze (now European Advanced
Superconductors, Germany)
develop and construct a large-aperture (up to 88
mm), high-field (up to 15 T) dipole magnet model
that pushes the technology well beyond present
LHC limits.
Next European Dipole
European Joint Research Activity
proof-of principle world record 16 T at 4.2 K
at LBNL (in 10 mm aperture).
(S. Gourlay, A. Devred)
60
proposed design of 24-T block-coil dipole for
LHCenergy tripler
P. McIntyre, Texas AM, PAC05
magnets are getting more efficient!
61
  • nominal LHC is extremely challenging
  • two paths to 10x higher luminosity
  • LHC experience will determine the choice
  • IR upgrade alone factor 2-5 increase
    integration of D0 or Q0 in ATLAS? questions of
    joint interest
  • raising beam intensity factor 2-4 gain
  • new injectors 3x higher peak average
    luminosity 1st step of energy upgrade
  • vigorous RD programme needed

62
2008 LHC Upgrade Conceptual Design Report 2010
LHC Upgrade Technical Design Report 2015 New IR,
Beam-Beam Compensation gt2015 Luminosity 5x1034
cm-2s-1
Francesco Ruggiero
63
please feel invited to join the LHC
effort! thank you for your attention!
also many thanks to Ohmi-san for organizing this
seminar!
64
appendix
  • beam lifetime and effective luminosity
  • details on installed magnets
  • parameter evolution and rates

65
run time integrated luminosity
collisions, gas scattering
intensity evolution for collisions only
intrabeam scattering (IBS) growth
burn-off collision lifetime with s100 mbarn,
nIP2 Lpeak1034 cm-2s-1 in 2808 bunches,
Nb1.15x1011 t45 h (luminosity lifetime 22
h) Lpeak1035 cm-2s-1 in 5616 bunches,
Nb1.7x1011 t14 h (luminosity lifetime 7
h) tgas gt 100 h (luminosity lifetime 50
h) tIBS105 h (horizontal emittance growth time
luminosity lifetime 210 h) burn-off dominates
over gas scattering and IBS
66
luminosity time evolution
average luminosity
?
opt. run time
effective decay time
opt. av. luminosity
Lpeak cm-2 s-1 beam lifetime teff h Tturnaround h Trun h Int L over 200 days fb-1
1034 45 10 21 79
1034 45 5 15 97
1035 14 10 12 473
1035 14 5 8 629
6x
8x
smaller b allows for lower beam current in LHC,
but increases events/crossing it reduces the
beam luminosity lifetimes
67
Lyn Evans, LHC MAC 07.12.2006
68
Parameter evolution and rates
All values for nominal emittance, 7TeV and 10m ?
in points 2 and 8
Parameters Parameters Parameters Beam levels Beam levels Rates in 1 and 5 Rates in 1 and 5 Rates in 2 (and 8) Rates in 2 (and 8)
kb N ? 1,5 (m) Ibeam proton Ebeam (MJ) Luminosity (cm-2s-1) Events/ crossing Luminosity (cm-2s-1) Events/ crossing
43 4 1010 11 1.7 1012 2 1.1 1030 ltlt 1 1.2 1030 0.15
43 4 1010 2 1.7 1012 2 6.1 1030 0.76 1.2 1030 0.15
156 4 1010 2 6.2 1012 7 2.2 1031 0.76 4.4 1030 0.15
156 9 1010 2 1.4 1013 16 1.1 1032 3.9 2.2 1031 0.77
936 4 1010 11 3.7 1013 42 2.4 1031 ltlt 1 2.6 1031 0.15
936 4 1010 2 3.7 1013 42 1.3 1032 0.73 2.6 1031 0.15
936 6 1010 2 5.6 1013 63 2.9 1032 1.6 6.0 1031 0.34
936 9 1010 1 8.4 1013 94 1.2 1033 7 1.3 1032 0.76
2808 4 1010 11 1.1 1014 126 7.2 1031 ltlt 1 7.9 1031 0.15
2808 4 1010 2 1.1 1014 126 3.8 1032 0.72 7.9 1031 0.15
2808 5 1010 1 1.4 1014 157 1.1 1033 2.1 1.2 1032 0.24
2808 5 1010 0.55 1.4 1014 157 1.9 1033 3.6 1.2 1032 0.24
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