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Siegfried BethkeMax-Planck-Institut für Physik(Werner Heisenberg Institut)
München
The Large Hadron Collider Projecton the cusp of New Physics
String Phenomenology 2005
• The Standard Model: successes, failures
and beyond
• LHC status: - Accelerator
- Detectors
• LHC physics: - Higgs boson searches
- Supersymmetry
- Large Extra Dimensions
2The Large Hadron Collider Project S.Bethke String Phenomenology, Munich, June 13-18, 2005
The „Standard Model“ (SM) of particle physics, describingthe unified Electroweak and the Strong Interactionsby means of gauge invariant quantum field theories,
is extremely successfulin precisely and consistently describingall particle reactions studied to date.
electro-weak precision measurements: precision measurements of the strong
coupling: Asymptotic Freedom
Nobel Prize 2004 in Physics for
Gross, Wi lczek und Politzer
(logarithmic) sensitivity
to mass of the Higgs boson
In el.-weak precision fits:
3The Large Hadron Collider Project S.Bethke String Phenomenology, Munich, June 13-18, 2005
However...
The SM works extremely well …
–> obvious first priority for future projects:
So far, there is no compelling higgsless model for e.w. symmetry breaking!
find the Higgs and declare particle physics solved!
4The Large Hadron Collider Project S.Bethke String Phenomenology, Munich, June 13-18, 2005
from particle physics:
there are hints and indicationsfor physics beyond the SM
• some cross sections start to violate unitarity at very high energies (~TeV)
• many free parameters (couplings, masses,..)
• general problems: fine tuning; hierarchy; ...
• couplings don‘t unify
– Theory:
– Experiment:
• low energy precision measurements: muon anomalous magnetic moment too big?
• high energy precision measurements: (slightly) improved description by SUSY?
• Quantum Gravity ?
5The Large Hadron Collider Project S.Bethke String Phenomenology, Munich, June 13-18, 2005
Gauge Unifications and Coupling Constants
SM MSSM
1 = (5/3) M S / cos2wM S
2 = M S / sin wM S
3 = sM S
de Boer & Sander, PLB585 (2004) 276
6The Large Hadron Collider Project S.Bethke String Phenomenology, Munich, June 13-18, 2005
Gauge Unifications and Coupling Constants
de Boer & Sander, PLB585 (2004) 276
mSUGRA fit of MSUSY= m0 = m1/2 and MGUT to world electroweak precision data
(LEP, SLC, b –> s , (g-2)μ )
7The Large Hadron Collider Project S.Bethke String Phenomenology, Munich, June 13-18, 2005
de Boer & Sander, PLB585 (2004) 276
Global fits to world precision ew data
• slightly improved fit quality of SUSY-models
– however –
• mostly due to aμ measurement
8The Large Hadron Collider Project S.Bethke String Phenomenology, Munich, June 13-18, 2005
M = 0.27 ± 0.04 (matter density)
= 0.73 ± 0.04 (dark energy)
B = 0.044 ± 0.004 (baryonic matter)
DM = 0.23 ± 0.04 (dark matter, DM= M- B)
Main candidates of (cold) DM: SUSY-WIMPs; Axions;primordial black holes
... today we know that the SM fails to describe
~95% of the total energy-/matter-density of the universe
... today we know that the SM fails to describe
~95% of the total energy-/matter-density of the universe
from astro physics:
9The Large Hadron Collider Project S.Bethke String Phenomenology, Munich, June 13-18, 2005
the most en vogue candidatesto solve (some of) these problems:
• Supersymmetry (SUSY) + fully compatible with and supported by GUT’s + offers excellent Dark Matter candidates + theory finite and computable up to Planck Mass + essential for realisation of string theory (including quantum gravity) - no SUSY signals seen yet (LEP, Tevatron) - (too) many free parameters, large parameter space
• Extra Space Dimensions + would solve hierarchy problem (MPlanck –> O(1 TeV)) + inspired by string theory: compactified extra dimensions +- exciting scenarios, but cannot solve many of above problems? - large model dependences
10The Large Hadron Collider Project S.Bethke String Phenomenology, Munich, June 13-18, 2005
particle physics: current exp. SUSY mass limits
Msleptons > 85 ... 100 GeV Msquarks > 100 GeV
Mgluino > 190 GeV
11The Large Hadron Collider Project S.Bethke String Phenomenology, Munich, June 13-18, 2005
particle physics: exp. limits for tan and mh0
CP-conserving MSSMwith max. upper bound on mh0 CP-violating MSSM
93 GeV < Mh0 < 140 GeV (tan 5)
114 GeV < Mh0 < 140 GeV (tan < 5)
2 < tan < 11
MH1 < 126 GeV
LHWG-Note 2004-01
• strongly depend on details of SUSY model (symmetry breaking scenario, CP violation,
mixing parameters,...) !
SM: 114.4 GeV < MH (95% c.l.)
12The Large Hadron Collider Project S.Bethke String Phenomenology, Munich, June 13-18, 2005
particle physics: exp. limits for tan( ) and mLSP=mconstrained MSSM (sleptons unify at m0, gauginos at m1/2)
47 GeV < m (large tan )
13The Large Hadron Collider Project S.Bethke String Phenomenology, Munich, June 13-18, 2005
• Vier geplante Experimente: ATLAS, CMS (pp-Physik) LHC-B (Physik der b-Quarks) ALICE (Pb-Pb Kollisionen)
• Gebaut in einer internationalen Kollaboration aus 34 Ländern
• Geplante Inbetriebnahme: 2007
Der Large Hadron Collider (LHC) • Proton-Proton Beschleuniger im
LEP-Tunnel am CERN
p p
7 TeV 7 TeV
- Höchste Energien pro Kollision - Höchste Luminositäten
Beantwortung der (meisten) offenen, fundmentalen Fragen:
14The Large Hadron Collider Project S.Bethke String Phenomenology, Munich, June 13-18, 2005
Proton – Proton Kollisionen:
2835 x 2835 Pakete (bunches)Abstand: 7.5 m ( 25 ns)
1011 Protonen / bunch Kreuzungsrate der p-Pakete: 40 Mio. mal / sec. Luminosität: L = 1034 cm-2 sec-1
Proton-Proton Kollisionen: ~109 / sec(Überlagerung von 23 pp-Wechselwirkungen während einer Strahlkreuzung)
~1600 geladene Teilchen im Detektor
hohe Anforderungen an die Detektoren
Der Large Hadron Collider (LHC)
15The Large Hadron Collider Project S.Bethke String Phenomenology, Munich, June 13-18, 2005
OPAL
ALEPHL3
DELPHI
European Centre for Particle PhysicsCERN / Geneva
LEP / LHC
SPS
LEP: e+e– collisions 1989 – 2000
LHC: p–p collisions from 2007
ATLAS
CMS
LHCb
Alice
16The Large Hadron Collider Project S.Bethke String Phenomenology, Munich, June 13-18, 2005
The LHC machine First full LHC cell (~ 120 m long) :
6 dipoles + 4 quadrupoles;
successful tests at nominal current (12 kA)
More than half of the 1232 dipoles are produced
8.4 Tesla
17The Large Hadron Collider Project S.Bethke String Phenomenology, Munich, June 13-18, 2005
The magnet production proceeds very well and
is on schedule, also the quality of the magnets
is very good
On the critical path for the first collisions, which
are planned for Summer 2007, is the installation
of the LHC in the tunnel, in particular due to
delays in the cryogenic services lines (QRL)
which initially had problems, and for which a
recovery plan was implemented successfullyDipole installation in the tunnel
Dipoles ready for installation
Cryogenics (QRL) in the tunnel
LHC construction and installation
18The Large Hadron Collider Project S.Bethke String Phenomenology, Munich, June 13-18, 2005
Lowering of the first dipole
into the tunnel (March 2005)
Installation of dipoles in the
LHC ring has started
19The Large Hadron Collider Project S.Bethke String Phenomenology, Munich, June 13-18, 2005
Interconnection of the dipoles
and connection to the cryoline
are the real challenges now in
the installation process
A view of the tunnel….
20The Large Hadron Collider Project S.Bethke String Phenomenology, Munich, June 13-18, 2005
ATLAS at the Large Hadron Collider / CERN
Construction until 2006, operation from 2007, for ~ 15-20 years
Length: 44 m
Height: 22 m
Weight : 7000 t
1800 Physicists & Engineers
150 Institutes
35 Nations
150•106 elektron. Read out channels
40 MHz collision rate
1014 B/s raw data flux
21The Large Hadron Collider Project S.Bethke String Phenomenology, Munich, June 13-18, 2005
ATLAS
Collaboration
34 Countries
151 Institutions
1770 Scientific Authors
Albany, Alberta, NIKHEF Amsterdam, Ankara, LAPP Annecy, Argonne NL, Arizona, UT Arlington, Athens, NTU Athens, Baku,
IFAE Barcelona, Belgrade, Bergen, Berkeley LBL and UC, Bern, Birmingham, Bonn, Boston, Brandeis, Bratislava/SAS Kosice,
Brookhaven NL, Bucharest, Cambridge, Carleton, Casablanca/Rabat, CERN, Chinese Cluster, Chicago, Clermont-Ferrand,
Columbia, NBI Copenhagen, Cosenza, INP Cracow, FPNT Cracow, Dortmund, JINR Dubna, Duke, Frascati, Freiburg, Geneva,
Genoa, Glasgow, LPSC Grenoble, Technion Haifa, Hampton, Harvard, Heidelberg, Hiroshima, Hiroshima IT, Indiana, Innsbruck,
Iowa SU, Irvine UC, Istanbul Bogazici, KEK, Kobe, Kyoto, Kyoto UE, Lancaster, Lecce, Lisbon LIP, Liverpool, Ljubljana,
QMW London, RHBNC London, UC London, Lund, UA Madrid, Mainz, Manchester, Mannheim, CPPM Marseille, Massachusetts,
MIT, Melbourne, Michigan, Michigan SU, Milano, Minsk NAS, Minsk NCPHEP, Montreal, FIAN Moscow, ITEP Moscow,
MEPhI Moscow, MSU Moscow, Munich LMU, MPI Munich, Nagasaki IAS, Naples, Naruto UE, New Mexico, Nijmegen,
BINP Novosibirsk, Ohio SU, Okayama, Oklahoma, LAL Orsay, Oslo, Oxford, Paris VI and VII, Pavia, Pennsylvania, Pisa,
Pittsburgh, CAS Prague, CU Prague, TU Prague, IHEP Protvino, Ritsumeikan, UFRJ Rio de Janeiro, Rochester, Rome I, Rome II,
Rome III, Rutherford Appleton Laboratory, DAPNIA Saclay, Santa Cruz UC, Sheffield, Shinshu, Siegen, Simon Fraser Burnaby,
Southern Methodist Dallas, NPI Petersburg, Stockholm, KTH Stockholm, Stony Brook, Sydney, AS Taipei, Tbilisi, Tel Aviv,
Thessaloniki, Tokyo ICEPP, Tokyo MU, Tokyo UAT, Toronto, TRIUMF, Tsukuba, Tufts, Udine, Uppsala, Urbana UI, Valencia,
UBC Vancouver, Victoria, Washington, Weizmann Rehovot, Wisconsin, Wuppertal, Yale, Yerevan
22The Large Hadron Collider Project S.Bethke String Phenomenology, Munich, June 13-18, 2005
Toroid system
Barrel Toroid parameters
25.3 m length
20.1 m outer diameter
8 coils
1.08 GJ stored energy
370 tons cold mass
830 tons weight
4 T on superconductor
56 km Al/NbTi/Cu conductor
20.5 kA nominal current
4.7 K working point
End-Cap Toroid parameters
5.0 m axial length
10.7 m outer diameter
2x8 coils
2x0.25 GJ stored energy
2x160 tons cold mass
2x240 tons weight
4 T on superconductor
2x13 km Al/NbTi/Cu conductor
20.5 kA nominal current
4.7 K working point
End-Cap Toroid:
8 coils in a common cryostat
Barrel Toroid:
8 separate coils
ATLAS Cavern April 2004
24The Large Hadron Collider Project S.Bethke String Phenomenology, Munich, June 13-18, 2005
Barrel Toroid coil transport and installation
ATLAS Pit (december 2004)
February 2005
May 2005
28The Large Hadron Collider Project S.Bethke String Phenomenology, Munich, June 13-18, 2005
May 2005
virtual reality: planned status for August 2005 …
30The Large Hadron Collider Project S.Bethke String Phenomenology, Munich, June 13-18, 2005
H
L
T
D
A
T
A
F
L
O
W
40 MHz
75 kHz
~2 kHz
~ 200 Hz
120 GB/s
~ 300 MB/s
~2+4 GB/s
Event Building N/workDataflow Manager
Sub-Farm Input
Event BuilderEB
SFI
EBNDFM
Lvl2 acc = ~2 kHz
Event Filter N/work
Sub-Farm Output
Event Filter
Processors EFN
SFO
Event Filter
EFPEFP
EFPEFP
~ sec
~4 G
B/s
EFacc = ~0.2 kHz
Trigger DAQ
RoI Builder
L2 Supervisor
L2 N/work
L2 Proc Unit
Read-Out Drivers
FE Pipelines
Read-Out Sub-systems
Read-Out Buffers
Read-Out Links
ROS
120 GB/s
ROB ROB ROB
LV
L1
D
E
T
R/O
2.5
μs
Calo
MuTrCh Other detectors
Lvl1 acc = 75 kHz
40 MHz
RODRODROD
LVL2 ~ 10 ms
ROIB
L2P
L2SV
L2N
RoI
RoI data = 1-2%
RoI
requests
Trigger, DAQ and Detector Control
31The Large Hadron Collider Project S.Bethke String Phenomenology, Munich, June 13-18, 2005
LHC Data and Computingthe challenge:
• 40 MHz collision rate –> unfiltered data flow ~ 1014 B/s
• 4 experiments; 50-200 Hz data taking rate
• raw event size: 0.12 / 1 / 1-25 MB (LHCb / ATLAS-CMS / ALICE)
• total raw data storage: 7 PB/a
• total simulated Data storage: 3.2 PB/a
• world-wide* tape storage: 28.5 PB/a (40 million CD-Rom’s)
• world-wide* disk storage: 10.4 PB/a (140k disks à 75 GB)
• world-wide* CPU capacity: 7350 k SI-95 (360k today’s PCs)
• WAN bandwidth (Tier-0/-1): 1500 Mbps (1 experiment)
* all Tier-0, Tier-1 and Tier-2 computing centres, excl. Tier-3 and -4
(5000 Mbps when serving all 4 exp.’s)
(7•1015 Bytes/year;100 000 km thick pile of A4-paper)
(~10 Billion phone calls)
32The Large Hadron Collider Project S.Bethke String Phenomenology, Munich, June 13-18, 2005
SUSY Searches at the Large Hadron Collider
Length: 44 m
Height: 22 m
Weight: 7000 t
1800 Physicists & Engineers
150 Institutes
35 Nations
150•106 electronic read-out channels
40 MHz collision rate
1014 B/s raw data flux
ATLAS
• if SUSY realised at TeV scale: guaranteed discovery at LHC!
• SUSY discovery straight forward, clear signatures (jets, Et
miss)
• separation of processes and distinction between models difficult
• if R-parity conserved: no mass peaks!
• instead, will analyse – end points of spectra– mass differences of states in decay chains
• end of construction: 2006 data taking: 2007 ... > 2020
33The Large Hadron Collider Project S.Bethke String Phenomenology, Munich, June 13-18, 2005
Higgs & SUSY Searches at the Large Hadron Collider
SM Higgs sensitivity (~ h0 in MSSM):
Squark and gluino masses in mSUGRA:
10 fb-1 ––> 1st year at initial Luminosity of 1033 s-1 cm-2
100 fb-1 ––> first 3 years with Luminosity –> 1034 s-1 cm-2
34The Large Hadron Collider Project S.Bethke String Phenomenology, Munich, June 13-18, 2005
Detection of Extra Dimensions at the LHC:
direct graviton production pp –> jet ETmiss
virtual graviton exchange in pp –>
(100 fb-1; i.e. 1 year at design luminosity)
35The Large Hadron Collider Project S.Bethke String Phenomenology, Munich, June 13-18, 2005
Summary• the Large Hadron Collider is the largest and one of the technologically most challenging projects ever realised in basic scientific research.
• it is designed to answer some of the most fundamental and still open questions of natural sciences, about the structure of matter, the nature of forces and the origin of our universe.
• Both the LHC accelerator and the big detector experiments will be ready to start commissioning and operation by end of 2006. First collisions and views into the new energy domain are planned for summer 2007, substantial luminosity will be collected from 2008 onwards.
• there are many indications, both experimental and theoretical, that there is New Physics beyond the Standard Model, possibly realised at TeV scales. LHC is designed to discover such new effects, and to explore their nature.
• among many models and new theoretical developments, the search for and discovery of Supersymmetry and of Extra Space Dimensions range among the most promising and exciting possibilities.
• If any or both of them will be found at LHC, this will be the first experimental clue towards phenomenological relevance of String Theories!
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