James L. Pinfold
University of Alberta
The
LHC
Collider
The
LHC
Experiments
LHC ring ~26km in circ.
368 SC quads (B/L=223T/m L=3.1m)
1232 SC dipoles (B=8.33T, L=14.2m)
Cryogenic system (1.8 K, super fluid He)
27 km of 8T magnets 100 m below surface
SCHEDULE
•March 2007:
•Nov. 2007:
•2008:
•2009-10:
•2011-17:
James L. Pinfold
Last magnet installed & machine closed March 2007
LHC commissioning run – 1st collisions at Eb =450 GeV)
First physics (starting in April) run 10 fb-1 L~ 1033 cm-2s-1
Low luminosity run 20-70 fb-1 L ~10331034 cm-2s-1
High luminosity run at 100 fb-1/year L ~1034 cm-2s-1
IVECHRI 2006
1
The LHC Experiments

ATLAS & CMS
ATLAS
Higgs physics, SUSY, EDs…
QCD, Top Physics,
Heavy-ions

LHCb
CP Violation

ALICE
ALICE
CMS
Quark-Gluon Plasma

TOTEM
Total pp x-section,
forward physics

MoEDAL (LoI)
Monopole search*

LHCF (LoI)
LHCb
Forward physics, prod. x-sect
measurement #
James L. Pinfold
IVECHRI 2006
2
LHC Operation in a Normal Year
LHC OPERATION
 140-180 days of running per year
 100-120 days of p-p collisions per year
 4 x 106s of proton luminosity running per
year.
 Around 40 days of heavy-ion (30 days) and
TOTEM running per year
HEAVY ION PROGRAM (at present)
 LHC Phase I: Collisions with Pb ions
“baseline programme”
 LHC Phase II: Collisions with lighter ions
(A-A collisions –Cand’s: He, O, Ar, Kr, In)
 LHC Upgrade Programme: so-called hybrid
collisions (e.g. p-A collisions - Pb, Ar, 0)
James L. Pinfold
IVECHRI 2006
3
Collider & Cosmics Energy Spectrum
Knee
(~1015eV)
I particle/
(m2 year)
Ankle(~1018 eV
1 particle/
(km2 century)

Proton-(anti)Proton cross-sections – important for measuring extended
air shower development (EAS), every primary particle produces an EAS
James L. Pinfold
IVECHRI 2006
4
Astro-Collider Physics– the Synergies
Direct Detection of Cosmic
Rays in Collider Detectors
(CosmoLEPCosmoLHC – so far ACORDE)
Forward Collider Physics
Few particles with low pT
but very high energy (90%
of event relevant to the
understanding of HECR, etc.
High PT Collider Physics
Involving ETmiss, jet
production, lepton ID, etc
Relevant to Dark Matter,
Extra Dimensions, etc.
James L. Pinfold
Astroparticle
Physics &
Cosmology
IVECHRI 2006
5
The ATLAS Collaboration
35 nations
158 institutions
~1650 scientists
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, Bologna, Bonn, Boston, Brandeis, Bratislava/SAS Kosice,
Brookhaven NL, Buenos Aires, Bucharest, Cambridge, Carleton, Casablanca/Rabat, CERN, Chinese Cluster, Chicago, ClermontFerrand, Columbia, NBI Copenhagen, Cosenza, INP Cracow, FPNT Cracow, Dortmund, TU Dresden, JINR Dubna, Duke, Frascati,
Freiburg, Geneva, Genoa, Giessen, 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, UN La Plata, 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, McGill 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, Oklahoma SU, Oregon, LAL Orsay, Osaka, 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, Toronto, TRIUMF, Tsukuba, Tufts, Udine, Uppsala, Urbana UI,
Valencia, UBC Vancouver, Victoria, Washington, Weizmann Rehovot, Wisconsin, Wuppertal, Yale, Yerevan
James L. Pinfold
IVECHRI 2006
6
The Experimental Challenge

High interaction rate
pp interaction rate 109 interactions/s
 Only ~100 events chosen out of 40 MHz event rate
 Level-1 trigger decision will take 2-3 ms
Electronics needs to store data locally (pipelining)


Large particle multiplicity
<23> superposed events in each crossing
 ~100 tracks stream into the detector each 25 ns
Need highly granular detectors with good time resolution for low occupancy


Very good muon ID and momentum measurement
trigger efficiently and measure the sign of a few TeV muons

Good energy resolution in the EM calorimetry (eg for Hgg)
~0.5% @ ET~50 GeV

Precise inner tracking for good mom. resolution & vertexing (b-decays
~10 better momentum resolution than at LEP

Hermetic calorimeter
Good ETmiss resolution

High Radiation levels (10MRads/yr & 1014 n’s/cm2/yr in the Forward reg)
Need radiation hard detectors and electronics
James L. Pinfold
IVECHRI 2006
7
The ATLAS Detector
E

pT
(IDet+m )  (0.009 pT /GeV  1.4)%

pT
E
( e, g ) 
10%
 0.3%
E /GeV
 
60 mrad
E /GeV
Mass –7000 tons
Length – 46 m
Diameter – 25m
Cost ~ 500 MCHF
X-sec thru the barrel
reveals the typical
onion structure of
A collider detector
(Inner Det)  (0.03 pT /GeV  1.2)%
 – pixel,
50 %silicon strip, TRT
Inner Tracker
2T
LAr EM Calorimeter -- good e/g ID,
( jet) 
 2%
E
E /GeV
solenoidal field,
good
e/g ID, e/p sep, t/b tag
energy & ETmiss resolution
Muon spectrometer – air core toroids Coverage in |h| - tracker < 2.5, cal < 4.9
B.dl = 2-6Tm (4-8 Tm)
E
James L. Pinfold
IVECHRI 2006
8
The Triggering & Data Challenge
Trigger system - Real time multilevel trigger to filter out background
and reduce data volume
40 MHz (40 TB/s)
Level 1 – special hardware processors
75 KHz (75 GB/s)
Level 2 – embedded processors + PC farms
1-KHz (1-GB/s)
Level 3 – PC farms
100 Hz (100 MB/s)
Data recording and offline analysis
Data recording rate for ATLAS ~0.1 GB/s ~1 PetaByte / LHCyear
James L. Pinfold
IVECHRI 2006
9
ATLAS Construction Progress
ATLAS Point-1
(July 2006)
All surface infrastructure operational





July 27th 2006 webcam Image
Magnets: Barrel Toroids + 2 End Cap Toroids + Central Solenoid + Cryogenics +
Services - Construct (8 years) 1998-06. Install (3 yrs) 2004-07
Muon Spectrometer: Barrel precision & trigger chambers + small & big forward
wheels + alignment - Produce (8 yrs) 1998-05. Install (3 yrs) 2005-07
Calorimeters: EM LAr + HAD LAr + LAr forward + HAD Tiles + cryogenics +
services – Produce (10 yrs) 1996-05. Install (3 yrs) 2004-06
Tracking: Pixels+SCT+TRT+services - Produce ( 8 yrs) 1999-06. Install (1 yr) 2006- 07
TDAQ systems are being assembled at Point 1. Offline software and computing
activities: are underway using the Worldwide LHC Computing Grid (WLCG)
James L. Pinfold
IVECHRI 2006
10
First ATLAS Data – Cosmic Rays!

Cosmic ray muons observed in the Tile Calorimeter (left) and in the
barrel region of the Inner Detector (right)
James L. Pinfold
IVECHRI 2006
11
ATLAS Coverage in Forward Direction
)
ZDC
FP420
Inst-TAS
Inst-TAS
James L. Pinfold
IVECHRI 2006
12
LHC Forward Physics & Cosmic Rays


Measurement of forward hadronic particle
production at the LHC will play a key role in
understanding UHECR EAS where major in
uncertainties in our understanding still exist
The NEEDS workshop (Karlsruhre 2002)
listed the hadronic interaction data (pp/pA/
AA) required from collider measurements:
measurement of tot& inel. p-p x-sec
 Energy distribution of leading FS nucleon
 Measurement of diff/inel
 Inclusive p-spectra in the frag. region xF >0.1
 Precise

ET (LHC)
The phenomenological models describing
non-perturbative QCD hadronic multiparticle production in HECR simulation,are:
 Low/medium
energy: GHEISHA, FLUKA,
UrQMD, TARGET, HADRIN, etc
 High energy: DPMJETII.5 &III, neXus 3.0,
QGSjet 01, SIBYLL 2.1, etc

E(LHC)
The models describe the Tevatron well - but
LHC model predictions reveal large
discrepancies in extrapolation
James L. Pinfold
IVECHRI 2006
13
The p-p Total Cross-section





The ATLAS approach is to measure elastic
scattering down to such small t-values that
the cross section becomes sensitive to the
EM amp. via the Coulomb interference term.
In this case an additional valuable constraint
is available from the well-known EM
amplitude, as can be seen from:
that describes elastic scattering at small t
T, L and the slope parameter b can be
determined by a fit to the above expression
At 7 TeV the strong amplitude is equal to the
EM amplitude for |t| = 0.00065 GeV2. This
corresponds to a scattering angle of 3.5 µrad
– thus we need special beam optics
LHC measurement of TOT expected to be at
the 1% level – useful in the extrapolation up
to HECR energies
James L. Pinfold
IVECHRI 2006
10% difference in
measurements of
Tevatron Expts:
(log s)g
14
ATLAS the Knee and the GZK Cutoff

Can hadron colliders can contribute to our
understanding of the knee? Yes, if the
knee is due to new physics:
 The
production of massive short lived (high
spin) particles in PeV CR interactions
(Petrukhin ISVECRI 2004)
 Or a new threshold? EG: the Colour Sextet
Quark Model (Alan White).





Knee
Both approaches predict multiple W/Z
production (large leptonic component)
The Tevatron energy is just too low but the
LHC could see a clear effect
Mx ≥ 1012 GeV
Can ATLAS contribute to our knowledge of
events above the GZK cut-off (~1019eV)?
Yes, if UHECRs (LSP’s, n’s, g’s & p’s)
result from the decay of a supermassive
relic particle Mx
Studies of the cascade decays of
sparticles at the LHC will be needed to
model the inclusive spectra from Mx decay.
James L. Pinfold
IVECHRI 2006
Ankle
Assume
SUSY
15
ATLAS, WMAP and Dark Matter

Inclusive constraints on CDM candidates from ATLAS/CMS – in year one
ATLAS
constraints
Direct
Detection
WMAP-results
jets+ETmiss+X
channel in ATLAS
M0 (GeV)
10 10  n ' s
Indirect detection
5 reach of the inclusive SUSY
searches at ATLAS for mSUGRA with
large tanb probing regions
inaccessible to the current DM expts
James L. Pinfold
WIMP-N
x-section (pb).
M0 (GeV)
The next direct DM searches (~1 ton)
will probe cosmologically favoured
regions (~10-10 pb) not accessible to
the LHC: 1) FP scenarios (large m0); 2)
models with large tan(b).
IVECHRI 2006
16
Black Holes – Exotic Evidence for EDs
Black Hole production at the
When particles are close
MBH ~ 8 TeV
ATLAS
LHC is possible in ED
they feel the effect of the
extra dimensions
scenarios - once the event
horizon is larger than a proton
only BHs would be produced!
 When Ecm reaches the
“Planck” scale, a BH is
formed; x-section is given by
the black disk: σ ~ πRS2
~ 1 TeV-2 ~ 10-38 m2 ~ 100 pb
 BHs decay ( ~ 10-26s) by
Hawking radiation: large
multiplicity, small ETmiss,
several jets/ leptons
 Gravity couples universally - new particles would be produced in BH decay
democratically – For the SM BHs  hadrons/ leptons/ /g,W,Z/Higgs ~
75%/20%/3%/2% BHs would be discovered by ATLAS/CMS with n=27 &
MD ≤ 6 TeV after one year at low luminosity
 BHs would also be created deep in the atmosphere by UHE neutrinos detect them (as horizontal air showers?) , e.g. in PAO, Ice3 or AGASSA
OFO 100 BHs can be detected before the LHC turns on

James L. Pinfold
IVECHRI 2006
17
Conclusions
The ATLAS Collaboration is ready , and on track, for p-p LHC physics in 2007
Collider results have only revealed the orthodoxy of the Standard Model but cosmic
ray physics hints of something new - centauros, strangelets,oh-my-God events,etc
The only physics at LEP at variance with the Standard Model was the anomalous
rate of high multiplicity muon bundles observed by the CosmoLEP expts
There is a considerable and growing synergy between collider & astroparticle
physics that we are ready to exploit to maximize the potential for gaining insights
into the fundamental nature of the universe
James L. Pinfold
IVECHRI 2006
20
EXTRA SLIDES
The Inner Part of Our Microscope
The Inner Detectors
ATLAS
CMS
ATLAS
Pixels: ~2m2, ~80M chs, rf/Z ~12/70mm, 50x400 mm size,3/6 B/EC lyrs 5-13cm
Si m-strps: ~60m2,~6M chs, rf/Z ~ 16/580mm, ptch 80mm, 4/18 B/EC lyrs 30-52cm
TRT: 36 strws/trk, ~400K chs, XeCO2O2, rf/Z ~ 170/170mm, B+EC lyrs 56-107cm –
electron ID.
CMS
Pixels: ~1m2, ~40M chs, rf/Z ~10/20mm, 100x150 mm size,3/4 B/EC lyrs 4-11cm
Si m-strps: ~220m2,~6M chs, rf/Z ~10/60mm, 6/9 B/EC lyrs 20-120cm
Transition Radiation Tracker
Radiator consists of
polystyrene fibrematting
ATLAS Calorimetry
EM Endcap
Calorimeter
Hadronic Endcap
Calorimeter
EM Barrel
Calorimeter
Forward
Calorimeter
Hadronic barrel
Calorimeter “tilecal”
The ATLAS Muon System
Barrel Toroid
Endcap Toroid
HECRs and Extended Air Showers
• EAS measurement is an
indirect method to find the
Mass & E of a primary CR
• Inferred from:
15 km
1016eV
100m
100m
From CosmoLEP to CosmoLHC
Overburden of ATLAS
• Like Cosmo-LEP (L3+C, Delphi, Aleph) ATLAS/CMS could be used to
measure CR events directly using unprecedented areas of precision mtracking and calorimetry ~100m underground
• ALICE is building ACORDE, ACORDE1 (scintillator array on top of
ALICE) is under construction, ACORDE2 (a surface array) & ACORDE 3
(m-detectors on the cavern floor) have been proposed
Physics with CosmoLHC
• Topics to study:
L3+C
– Single/inclusive m’s (pt spectrum >20 GeV  2
TeV, angular dist. 0 <  < 50o, charge ratio, etc.)
– Upward going m’s (E spectrum, angular
distribution, etc.)
– Multi muons (composition measurements, etc.)
– Muon bundles (evidence for new physics?)
– Isoburst events seen in LVD, KGF (an hyp. is
that they are due to the decay of WIMPS (M
> 10 GeV) – better measured at the LHC.)
A muon “bundle” event
ALEPH
• These measurements will yield data on:
– Forward physics of hadronic showers
– Primary composition of cosmic rays
– Time variation (sidereal anisotropies, bursts,
point sources, GRBs)
– New physics (eg anomalous muon bundles)?
CR m-multiplicity in ALEPH’s TPC
compared to CORSIKA simulations
for p & Fe incident primaries.