Visions of the Future: The Energy Frontier

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Visions of the Future The Energy Frontier
DornanFest Sep09, London
The High Energy Frontier at the LHC Machines of
the Future
Tejinder S. Virdee (CERN/Imperial College)
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The Standard Model of Particle Physics
The Standard Model of Particle Physics (circa Oct
1974)
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The Standard Model of Particle Physics
The Standard Model of Particle Physicshas been
built upon the discovery of particles over the
last few decades at lepton-lepton,
lepton-hadron and hadron-hadron colliders
?
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Successes of the Standard Model
LEP, SLC and the Tevatron established that we
really understand the physics at energies up to
vs 100 GeV
And any new particles have masses in the range of
hundreds of GeV and in some cases TeV.
Although the Standard Model is a beautiful theory
and arguably one that is most precisely
tested we know it is not the whole truth !
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Physics Outlook Questions
1. SM contains too many apparently arbitrary
features - presumably these should become clearer
as we make progress towards a unified theory.
3. SM gives nonsense at LHC energies Probability
of some processes becomes greater than 1 !!
Natures slap on the wrist! Higgs mechanism
provides a possible solution
4. Supersymmetry ? Even if the Higgs exists all
is not 100 well with SM alone next question is
why is (Higgs) mass so low? ?If a new symmetry
(Supersymmetry) is the answer, it must show up at
O(1TeV)
5. SM is logically incomplete does not
incorporate gravity Superstring theory
a?dramatic concepts supersymmetry , extra
space-time dimensions ?
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The Higgs Problem (a la Altarelli LP09)
The main problems of the SM show up in the Higgs
sector
Higgs, if it exists, appears to be light ?New
Physics near the weak scale e.g. Supersymmetry
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The Supersymmetry Issue

• Supersymmetry apparently plays an important role
  in
• Grand unification (strong electroweak forces)
• Proton decay
• Heirarchy problem - why is the Higgs mass so low
• Candidate for dark matter - lightest neutral
  sparticle
• String theory requires supersymmetry (towards
  reconciling gravity and QM)

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Experimentally at the LHC Energy Frontier
Find new particles/new symmetries/new forces?

• Clarify the e-w symmetry breaking sector Higgs
  boson(s),
• Supersymmetry e.g. identify particle(s) that
  make Dark Matter
• New Physics II Z, Extra space-time
  dimensions, Z etc. ?

• The Unexpected !!

It is almost impossible that LHC finds neither
the Higgs nor New Physics
Studies of CP Violation
and Quark Gluon Plasma
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The LHC Accelerator and Experiments
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The LHC Worked Well Before the Incident
Captured beam with optimum injection phasing,
correct reference
No RF, debunching in 2510 turns, i.e.
roughly 25 ms
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The LHC Experiments are Ready to Take Collision
Data Results from Cosmics Tests First LHC
Beam!
All indications are that the experiments are
performing as expected. They have come out of
the first maintenance cycle and are now ready for
collisions months before LHC restarts. Much
test beam work had preceded cosmics tests
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ATLAS
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CMS
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The Quality of Detectors is Excellent
The LHC detectors are in good shape to take high
quality collision data.
Example CMS comprises Tracker 66M pixel
channels, 10M Si microstrip channels, Calorimetry
75k crystals, 150k Preshower channels, 15k
HCAL channels, Muons System 250 DT chambers
(170k wires), 450 CSC chambers (200k wires) ,
500 Barrel RPCs and 400 endcap RPCs, Trigger
System muon and calorimeter trigger system, 40
kHz DAQ system ( 10k CPU cores), Worldwide
Computing Grid ( 50 k cores), Offline (gt 2M
lines of source code).
Only a few per mille to 1 of channels were not
operational during Oct/Nov08 Cosmics run. Even
better in Aug09 Cosmics run. Essentially with a
performance specified in the Technical Design
Reports (last century).
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CMS Continuous Operation - Cosmics Runs
CRAFT Cosmics Run at Four Tesla CRAFT08
Oct-Nov08 Ran CMS for 6 weeks continuously to
gain operational experience Collected 300M
cosmic events with tracking detectors and
field. About 0.5 PB of data distributed widely.
CRAFT09 Aug09 Collected 300M cosmic events
with tracking detectors and field.
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CMS Cosmics Run Some Results
Alignment Si Trkr TOB Modules
DMR TOBx 3.2 um
Momentum Resolution lt2-leggt
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• LCG/EGEE/OSG e-Science Grid is in production
• World-wide Coverage
• Over 200 sites
• gt 20000 CPUs
• Multi-petabyte storage

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First LHC Beam 10 Sep. 2008
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First LHC Beam Events Recorded by Xpts
ALICE
LHCb
CMS
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The Mass of the Higgs Boson ?
Radiative Corrections prediction of the range for
theHiggs mass
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Outline of LHC Early Physics Programme

• First collisions at injection energy, then at 7
  TeV
• Early beam collisions _at_ 7 TeV, integrate up to
  50pb-1, rediscover the S.M. and start
  searches
• Approx per pb-1 3000 W?l ? (l e,?) 300
  Z?ll (l e, ?) 5 ttbar ? ?X
• Safely move up to the higher energy towards 10
  TeV integrate hundreds pb-1 _at_ 10 TeV extend
  searches

Z-gt ee 10fb-1 _at_ 10 TeV Syst uncertainty 2.4
10 for ?Ldt
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First Few Hundred pb-1 _at_ 10 TeV
Signals and backgrounds are scaled from 14 TeV
Plots are indicative of CMS reach
10 TeV
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Higgs Boson - Reach
J.J. Blaising et al, input to Eur. Strategy
workshop
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ATLAS CMS Supersymmetry _at_ 14 TeV
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LHC/sLHC - Discovery Reach
sLHC extending the physics potential of the LHC
2011 2013 // arbitrary scale

2010 //
2018 //
2030
Assuming New Physics is found at the LHC New
Accelerator and Detectors Should start Operating
2030 Inform decision on which flavour by what
and when of the New Physics
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Higgs Boson _at_ Linear Collider
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Design Benchmarks Physics!
Broadly speaking physics benchmarks used 20
years ago were Higgs, SUSY and Z
Today essentially the same
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Design of Next Generation Detectors
The Easier Bit ?
Nevertheless challenges are still have to be
faced e.g. Low density tracking, Fine granularity
calorimetry, requiring RD
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Surface Assembly and Lowering of CMS
Feb 2007
Feb. 2007
1920 tons 1/3 of an Eifel Tower
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Cables, Pipes, Fibres
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Lowering to Data Taking 21 months
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Machine Flavours for the Future
What lies beyond the LHC ? Take a 50 year look
! hadron - hadron collider (sLHC / DLHC,
VLHC) lepton - lepton collider (ILC /
CLIC, Muon Collider) lepton - hadron collider
(LHeC)
Short-term Medium Term Long-term
LHeC
ILC
VLHC
LHeC
Muon Collider
40-140 GeV on 1 - 7 TeV
CLIC
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European Strategy
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Some Parameters of Future Machines
sLHC ILC CLIC MuC VLHC Energy (TeV) 14 0.5
-1 0.5-3 1.5-4 100 L (1034) 5-10 1-4 1 Rep
rate/Spacing 50ns 200ns Part/Bunch
(1011) 1 20 1 Acc Gradient MV/cm - 35 100 -
- Dimensions (km) 27r 10-50l 5-8r 100r Depth
(m) 13-135 Desired Timeline 2018 2013 2017
2020 ?
Project Approval Start of high L operation
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Looking Ahead SLHC
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Future machine - Schedules !
ILC Schedule
Muon Collider Schedule
CLIC Schedule
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A Phased Approach to the Muon Collider
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Timeline of Projects
The Best Indicator of the Timeline of
Construction is Expenditure E.g. CMS Expenditure
Took 12 years to construct CMS Required
effort of a Collaboration of 2500 scientists and
engineers
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Dark Side of the Universe Dark Matter
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Dark Side of the Universe Dark Energy
The Standar Model of Cosmology Convergence Model
It appears that the rate of expansion of the
universe is accelerating !! Dark Energy? Remnant
of some elementary scalar field analagous to the
Higgs field?
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Conclusions

• The future of Particle Physics rests on the LHC
  (but LHC should not be all).
• The LHC experiments are ready to record
  collisions expected in Q409.
• It has taken 20 years to get here.
• All the expectations are that what we will find
  at the LC will revolutionize our understanding of
  fundamental physics.
• Another 20 years are likely to be needed to
  fully extract the science from the LHC. The next
  machine should start operating lt 2030.
• Building the next generation of detectors should
  be easier than building the machine.
• The results from the LHC will illuminate the
  Terascale landscape allowing an informed decision
  on the choice of the next machine.

The real hope is to restore the exciting
environment of particle physics that we remember
from the 1960s and 1970s S. Weinberg (Sep09
CERN Courier)
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Peter

• Adviser
• Mentor
• Group Leader

• And a Friend

A Profound Thank You