The Large Hadron Collider Project · PDF fileThe Large Hadron Collider Project S.Bethke String Phenomenology, Munich, June 13-18, 2005 2 The „Standard Model“ (SM) of

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:


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!


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 ?


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


Gauge Unifications and Coupling Constants


mSUGRA fit of MSUSY= m0 = m1/2 and MGUT to world electroweak precision data

(LEP, SLC, b –> s , (g-2)μ )



Global fits to world precision ew data

• slightly improved fit quality of SUSY-models

– however –

• mostly due to aμ measurement


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:


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


particle physics: current exp. SUSY mass limits

Msleptons > 85 ... 100 GeV Msquarks > 100 GeV

Mgluino > 190 GeV


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.)


particle physics: exp. limits for tan( ) and mLSP=mconstrained MSSM (sleptons unify at m0, gauginos at m1/2)

47 GeV < m (large tan )


• 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:


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)


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


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


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


Lowering of the first dipole

into the tunnel (March 2005)

Installation of dipoles in the

LHC ring has started


Interconnection of the dipoles

and connection to the cryoline

are the real challenges now in

the installation process

A view of the tunnel….


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


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


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


Barrel Toroid coil transport and installation

ATLAS Pit (december 2004)

February 2005

May 2005


May 2005

virtual reality: planned status for August 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


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)


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


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


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)


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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The Large Hadron Collider Project · PDF fileThe Large Hadron Collider Project S.Bethke String Phenomenology, Munich, June 13-18, 2005 2 The „Standard Model“ (SM) of