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Home , ALICE experiment, ATLAS experiment, LHCb experiment

Advanced Topics in Particle Physics

Probing the High Energy Frontier at the LHC

Ulrich Husemann, Klaus Reygers, Ulrich Uwer University of Heidelberg Winter Semester 2009/2010

CERN = European Laboratory for Partice Physics the world’s largest particle physics laboratory, founded 1954 Historic name: “Conseil Européen pour la Recherche Nucléaire” Lake Geneva Proton-proton2500 employees, collider almost 10000 guest scientists from 85 nations

Jura Mountains 8.5 km

Accelerator complex Prévessin site (approx. 100 m underground) (France)

Meyrin site (Switzerland)

Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 2 Large Hadron Collider: CMS Experiment: Proton-Proton and Multi Purpose Detector Lead-Lead Collisions

LHCb Experiment: B Physics and CP Violation

ALICE-Experiment: ATLAS Experiment: Heavy Ion Physics Multi Purpose Detector

Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 3

The Lecture

“Probing the High Energy Frontier at the LHC” Large Hadron Collider (LHC) at CERN: premier address in experimental particle physics for the next 10+ years LHC restart this fall: ﬁrst beam scheduled for mid-November LHC and Heidelberg Experimental groups from Heidelberg participate in three out of four large LHC experiments (ALICE, ATLAS, LHCb) Theory groups working on LHC physics

→ Cornerstone of physics research in Heidelberg → Lots of exciting opportunities for young people

Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 4 Scope of this Lecture

Goal: Overview of most important physics topics pursued at the LHC

High-pT physics (mostly ATLAS and CMS) Flavor physics (mostly LHCb) Heavy ion physics (mostly ALICE) Target audience: Master/Diploma and graduate students with prior knowledge of theoretical and experimental particle physics Builds upon previous lecture(s) “Experimental Particle Physics” & “Introduction to the Standard Model” Part of program of the “Heidelberg Graduate School of Fundamental Physics”

Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 5

Organizational Issues

Advanced Topics in Particle Physics: “Probing the High Energy Frontier at the LHC” Date: Mondays, 14:00–16:00 c.t. (2 SWS) Room: INF 227 / HS 2 Lecturers:

Ulrich Husemann (KIP & DESY, ATLAS): High-pT Physics Tel.: 06221-54xxxx, E-Mail: [email protected] Klaus Reygers (PI, ALICE): Heavy Ion Physics Tel.: 06221-549317, E-Mail: [email protected] Ulrich Uwer (PI, LHCb): Flavor Physics Tel.: 06221-549226, E-Mail: [email protected]

Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 6 Preliminary Schedule # Date To p ic Lecturer 1 10/12/09 Introduction All 2 10/19/09 The LHC Multipurpose Experiments U. Husemann 3 10/26/09 Hadron Collider Basics U. Husemann 4 11/02/09 QCD, Factorization, Jets U. Husemann 5 11/09/09 W and Z Boson Production U. Husemann 6 11/16/09 To p Q u ar k Pro d u ct i o n U. Husemann 7 11/23/09 Higgs Physics U. Husemann 8 11/30/09 Supersymmetry U. Husemann 9 12/07/09 Exotic Models: Extra Dimensions etc. U. Husemann 10 12/14/09 U. Uwer 11 12/21/09 U. Uwer 12 01/11/10 U. Uwer 13 01/18/10 K. Reygers 14 01/25/10 K. Reygers 15 02/01/10 K. Reygers Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 7

Literature

The Particle Data Book, of course: http://pdg.lbl.gov Detailed papers on LHC machine and detectors published back-to-back in open-access journal before startup: Machine: 2008 JINST 3 S08001 ALICE: 2008 JINST 3 S08002 ATLAS: 2008 JINST 3 S08003 CMS: 2008 JINST 3 S08004 LHCb: 2008 JINST 3 S08005 More detailed literature lists for the individual topics later (few books, many review articles)

Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 8 Chapter 1

Introduction

A Little LHC History

The early days 1977: LEP tunnel to be built large enough for another ring 1984: First LHC workshops in Lausanne → superconducting 10 T (= 17 TeV) pp collider in LEP tunnel → feasibility of magnet design shown in late 1980ies 1990: Aachen workshop → evaluation of LHC physics potential 1992: Évian workshop → experiment proposals 1993: US congress terminates SSC (Superconducting Super Collider, 40 TeV) → integrate US physics community 1994: Approval by CERN Council Initial plan: two stages (10 TeV in 2004, 14 TeV in 2008, due to budget constraints), later changed to 14 TeV in 2005

Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 10 A Little LHC History

Construction phase 1998: civil engineering starts (experimental caverns and surface buildings) 2000: LEP terminated and dismantled from 2000: (pre-) production of magnets 2005–2007: magnet installation

[atlas.ch]

Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 11

A Little LHC History

LHC startup September 10, 2008: ﬁrst beam event, experiments (partly) switched on September 19, 2008: magnet incident stops LHC operation

November 2009: LHC restart Further details on LHC history: CERN Courier (issue of October 2008)

[CERN] Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 12 LHC Physics Program

Main LHC goal: search for the Higgs boson and physics beyond the standard model → high-pT & ﬂavor physics Broader physics program considered early on: Collisions at four points around the ring: two with large collision rates, two with medium collision rates Allow LHC operation with heavy ions (lead) Optimize design of machine and detector for above goals, given technical constraints: Tunnel: re-use from LEP accelerator → 27 km circumference Magnets: maximum B ﬁeld strength with available technology for superconducting dipole magnets → 9 Tesla → approx. 15 TeV center of mass energy

Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 13

High-pT Physics @ LHC

Hadron collider physics = discovery physics at the highest available energies (“energy frontier”), complementary to precision physics at e+e– colliders CERN Sp!S: 1982–1990 → W and Z boson discovery, searches for top quarks, SUSY… Fermilab Tevat ro n : 1987–2010 (2011?) → top quark discovery, Bs ﬂavor oscillations, searches for Higgs, SUSY, exotics… Next step in energy: explore energies around 1 TeV (“terascale”) → relevant scale for electroweak physics Machine & detector design goals: Highest possible energies and collision rates Versatile multi-purpose detectors

Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 14 Protons or Antiprotons?

Sp!S and Tevatron: proton-antiproton colliders At leading order many processes dominated by quark- antiquark annihilation, e.g. W and Z production, but: no valence antiquarks in proton → antiprotons

p p + + + ν¯", " e ,µ u, d u, d

± Z ¯ ¯ W ¯ ¯ d, u − u, d − − " , ν" e ,µ p¯ p¯

Particle and its antiparticle can be accelerated in the same structure (single beam pipe, same magnets, …) Problem: protons are “cheap”, but antiprotons are hard to produce (in proton beam dump) and to accumulate (“cooling”) → performance of collider limited by antiproton availability Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 15

Protons!

At LHC energies: Interesting ﬁnal states with a few 100 GeV (Higgs, top, …) produced by partons that carry small fraction x of proton momentum (more details on proton structure later) Important HERA result: gluons dominate at small x → don’t need valence antiquarks, e.g. for top pair production q W– p ! #’ " b t Ȟ p ȝ W+ ȝ+ Caveat: need separate acceleration structures (two rings or double ring)

Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 16 Heavy Ion Physics @ LHC

Heavy ion collisions: study strongly interacting matter at extreme energy densities → expect new phase of matter: quark-gluon plasma Experience from previous heavy ion programs, e.g. CERN ﬁxed target program: ions from SPS Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory: 200 GeV gold-gold collisions LHC: explore highest available energy densities Design goals: Allow for acceleration of heavy ions in addition to protons Dedicated experiment for heavy ion collisions: ALICE

Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 17

Flavor Physics @ LHC

Flavor physics: indirect search for new phenomena in very rare decays via loop effects → multi-TeV Central tool in ﬂavor physics: B hadrons → long history of ﬁxed-target and collider experiments, e.g. LEP and Tevat ro n multi-purpose experiments ARGUS & CLEO: e+e– collider experiments on ϒ(4S) resonance

BABAR & Belle (“B Factories”): experiments at asymmetric e+e– collider on ϒ(4S) resonance LHC: extremely high production rate of B hadrons Specialized interaction region with lower collision rates Dedicated experiment optimized for detecting B hadron decays

Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 18 Chapter 2

The LHC Accelerator Chain

Pre-Accelerator Chain

LHC beam to consist of: 2808 proton bunches with spacing of 25 ns (40 MHz, distance: 7.5 m), complicated bunch structure High intensity bunches (1011 protons/ bunch) with small longitudinal and transverse spread (“emittance”) Cannot accelerate beams from zero to 7 TeV in a single structure → need chain of pre-accelerators Re-use existing pre-accelerators Some upgrades necessary (Proton Synchrotron: 50 years old!)

Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 20 LHC Bunch Structure

[ATLAS L1 Trigger, Technical Design Report, 1998]

Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 21

Pre-Accelerator Chain

7 TeV protons in main LHC ring 450 GeV protons in Super Proton Synchrotron (SPS)

26 GeV protons in Proton Synchrotron (PS) 50 MeV – 1.4 GeV protons in LINAC/PS Booster

Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 22 [atlas.ch]

Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 23

LHC Layout

Basic layout: eight interaction points (IP), four with experiments, others for acceleration, beam dump, etc. [http://lhc.web.cern.ch/lhc/]

Status of LHC cool-down last Friday: everything below 4.5 K Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 24 Typical LHC “Fill”

Acceleration and preparation for “physics:” Injection from pre-accelerator chain (approx. 4 minutes) → protons circulating at 450 GeV Acceleration to 7 TeV (“ramp to ﬂat top,” approx. 20 minutes) Beam focusing at interaction points (“squeeze”) → collisions Collimation: remove non-bunched protons → ready for physics Experiments switch on and take data (< 24 hours) Controlled beam abort (“dumping the beam”) Extraction (“kicker”) magnets deﬂect beam into carbon block Abort can also be triggered by accelerator problems

Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 25

RF System

Radio-frequency (RF) system provides: Beam acceleration and beam energy loss compensation Formation of bunch structure LHC RF system:

400 MHz superconducting First LHC niobium/copper cavities: RF capture ﬁeld 5.5 MV/m Two independent RF systems of 8 cavities [O. Brüning, CERN] Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 26 RF Cavities

Switching every 1.25 ns (400 MHz) 2a

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Probing the High Energy Frontier atA%52#.$B6CD$A"2#4E)1%(8$E#8","/2*.$ the LHC, U Heidelberg, Winter Semester 09/10, Lecture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ipole! Magnets */1+%.#$20& Dipole magnets: keep beam on circular orbit P)+0$+#8","/2*.$0)'$)$'%&5*.$%&*.($!"#$*%Q2%/$0.*%2,$)&/$)$'%&5*.$"2(*.($!"#$(0.$0.*%2,$.1)-"#)(./$38$'()(%+$ )&/$ /8&),%+$ *"''.'6$ 70.$*.1.*$ %'$ #.52*)(./$ 38$ (0.$ %&-2($ 1)*1.$ 2'%&5$ !../3)+>$ !#",$ '2-.#+"&/2+(%&5$ ;%#.$ *.1.*$5)25.'$%&$(0.$+#8","/2*.6$70.$'()(%+$*"''.'$)#.$1232 main superconducting CMK$J$-.#$,"/2*.6$F($&",%&)*$!%.*/$(0.$RA$*"''.'$)#.$ CKK$J$dipole )&/$ )($ (;%+.$magnets, (0.$ &",%&)*$ 15 !%.*/$ m SKK$J$long -.#$ ,"/2*.?$ ,)>%&5$ (0.$ ("()*$ *"''.'$ TMK$J$ )&/$ UMK$J?$ #.'-.+(%1.*86$ A"#$"-.#)(%"&$)($&",%&)*$!%.*/$(0.$-#.''2#.$%&'%/.$(0.$“Twin-aperture” design: two 0.*%2,$()&>$0)'$("$3.$+)#.!2**8$+"&(#"**./$("$)1"%/$ !#.Q2.&+8$ 1)#%)(%"&'$ "!$ (0.$ +)1%(8?$ (0.$ '.&'%(%1%(8$ 3.%&5$ )&$ )--#.+%)3*.$ CMK$GVW,3)#6$ 70.$ ,)@%,2,$ .@+2#'%"&$)#"2&/$(0.$&",%&)*$1)*2.$"!$CXMK$,3)#$0)'$3separate beam pipes, 56 mm ..&$!%@./$("$YCM$,3)#6$70.$"-.#)(%"&$"!$(0.$+)1%(%.'$ ;%**$ 3.$aperture, 1.#8$ +#%(%+)*$ !#",$ 194 (0.$ mm -"%&($ separation "!$ 1%.;$ "!$ ')!.(8D$ (0.8$ 0)1.$ 3..&$ /.'%5&./$ ("$ ;%(0'()&/$ )$ ,)@%,2,$ -#.''2#.$ "!$ T$3)#$ )&/$ ;%**$ 3.$ +"&&.+(./$ ("$ (0.$ ZR[$ *%&.$ \$ %&$ ;0%+0$ -#.''2#.$ +)&$ #%'.$ ("$ 2-$ ("$ TK$3)#$ %!$ ,)5&.('$Q2.&+06$F$-#.''2#.$';%(+0$;%**$(0.#.!"#.$+*"'.$(0.$"2(-2($1)*1.$%!$(0.$-#.''2#.$%'$)3"1.$CMKK$,3)#6$ F$-"''%3%*%(8$-#.'.&(*8$3.%&5$'(2/%./$%'$("$-#"1%/.$)$+"&&Superconducting cables: NbTi .+(%"&$("$(0.$J)#,$R.+"1.#8$[%&.$]JR[^$("$.&'2#.$ (0.$')!.$/%'+0)#5.$"!$.1)-"#)(%&5$0.*%2,$%&$)&8$"-.#alloy )(%&5$,"/.6$70.$+)1%(%.'$;%**$%&$)&8$+)'.$3.$.Q2%--./$[CERN] ;%(0$ ')!.(8$ ]Q2.&+0^$ 1)*1.'$ ("$ /%'+0)#5.$ (0.$ 0.*%2,$ %&$ +)'.$ "!$ %&'2*)(%&5$ 1)+22,$ *"''$"#$ %&)3%*%(8$ ("$ /%'+0)#5.$%&("$*%&.$\$"#$(0.$JR[6$$Sophisticated cryogenic system $ Dipole magnets assembled and tested on surface, inter-magnet connections in LHC tunnel More than 7000 additional magnets: focusing & higher order corrections of beam orbit Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 28 LHC Dipole Magnets [CERN]

Dipole magnets

Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 29

Interaction Regions

Complicated sequence of dipole, MQXA Quadrupole quadrupole, and correction magnets to create collisions: Beam pipes are joined into same vacuum Triplet of “low-β” quadrupole magnets

to focus beam (Q1–Q3): 31 m long, [KEK] ±23!m from interaction point

Interaction region at ATLAS [2008 JINST 3 S08001]

Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 30 Figure 2.4: Schematic layout of the right side of IR1 (distances in m). 2008 JINST 3 S08001 magnets with separate beam pipes for each ring. From the IP up to the DS insertion the layout comprises:

A 31 m long superconducting low-βgriplet assembly, operated at a temperature of 1.9 K and • providing a nominal gradient of 205 T/m.

A pair of separation / recombination dipoles separated by approximately 88 m. • The D1 dipole located next to the triplet magnets, which has a single bore and consists of six • 3.4 m long conventional warm magnet modules yielding a nominal ﬁeld of 1.38 T.

The following D2 dipole, which is a 9.45 m long, twin bore, superconducting dipole magnet, • operating at a cryogenic temperature of 4.5 K with a nominal ﬁeld of 3.8 T. The bore separation in the D2 magnet is 188 mm and is thus slightly smaller than the arc bore separation.

Four matching quadrupole magnets. The ﬁrst quadrupole following the separation dipole • magnets, Q4, is a wide-aperture magnet operating at a cryogenic temperature of 4.5 K and yielding a nominal gradient of 160 T/m. The remaining three quadrupole magnets are normal-aperture quadrupole magnets, operating at a cryogenic temperature of 1.9 K with a nominal gradient of 200 T/m.

Figure 2.4 shows the schematic layout of IR1 on the right hand side. The triplet assembly features two different quadrupole designs: the outer two quadrupole magnets, made by KEK, require a peak current of 6450 A to reach the nominal gradient of 205 T/m, whereas the inner quadrupole block, consist of two quadrupole magnets made by FNAL, requires a peak current of 10630 A. The triplet quadrupoles are powered by two nested power converters: one 8 kA power converter powering all triplet quadrupole magnets in series and one 6 kA power converter supplying additional current only to the central two FNAL magnets. The Q1 quadrupole next to the IP features an additional 600 A trim power converter. Two absorbers protect the cold magnets from particles leaving the IP. The TAS absorber protects the triplet quadrupole magnets, and the TAN absorber, located in front of the D2 dipole magnet, protects the machine elements from neutral particles.

2.6 Medium luminosity insertion in IR2

The straight section of IR2 (see ﬁgures 2.5 and 2.6) houses the injection elements for Ring-1, as well as the ion beam experiment ALICE. During injection, the optics must obey the special con-

– 13 – Cryogenic System

Previous superconducting accelerators (Tevatron, HERA): supercritical helium (T > 4.2 K, boiling point of He) → magnetic field limited to B < 5 T LHC: superfluid helium (T < 2 K) LHC Helium Refrigeration Plant The world’s largest connected cryogenic system: 10000 tons of liquid nitrogen, 130 tons of liquid helium Advantage: zero viscosity & entropy, infinite thermal conductivity Caveat: heat capacity of superconducting cables drops by more than factor of two [CERN] Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 31

Vacuum System

Inside beam pipe: ultra-high vacuum (UHV) Low background from beam-gas interactions → long lifetimes From scattering cross section for protons in typical gases: -13 13 3 pressure < 10 hPa (equivalent of 10 H2 molecules per m )

UHV techniques at the LHC: Ion Pump Mobile pumps for initial vacuum Sputter ion pumps: ionize gas & accelerate in electric ﬁeld → molecules bound on surface Bake-out: heat beam pipe to 250°C → outgassing of volatile compounds [lesker.com] Beam pipe coating with TiZrV alloy (“non-evaporable getter”, forms compounds with active gasses) Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 32 Safety Systems

Large amount of energy stored in small area: Beam: 360 MJ (kinetic energy of ICE-3 at 150 km/h in 3×1014 protons → kinetic energy of a mosquito per proton) Magnets: 600 MJ of magnetic energy Danger of uncontrolled beam loss & “quenches” Typical problem of superconducting magnets: local loss of superconductivity (e.g. energy deposit by spray of protons) Consequences: high magnet currents (>10 kA) feel resistance → heat & helium vapor: danger of destroying magnet → magnetic ﬁeld drops: danger of losing beam Specialized electronics to detect quenches and induce controlled beam abort (“Quench Protection System”)

Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 33

The Incident

Incident on Sept 19, 2009 Faulty connection between two dipole magnets (“busbar”) ruptured Massive helium evaporation → collateral damage from Dipole pressure wave: displaced Busbar magnets Repair work: 53 magnets (39 dipoles) repaired on surface, beam pipe cleaned [CERN] Better helium pressure relief and instrumentation Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 34 ElectricalDipolejoint in 12 Busbars kA bus bar [M. Lamont, LHC status and commissioning, La Thuile ‘09] andThuile commissioning, La LHC status Lamont, [M.

Upper Copper ³:KDWPDNHVDJRRGMRLQW"´ Profile Superconducting Cable in Copper Upper Tin/Silver Stabilizer !"#$%&'%() Soldering alloy Layer

Lower Tin/Silver Soldering Alloy Layer Inter-Cable Tin/Silver Soldering Alloy Layer

Completed !#&%*(*+(,%#)-(.+#-/#01-2+# Junction 334#. '(+5#106#%7%8+&(807# Lower Copper U Profile Cable Junction Box 0.6#+5%&907#8-.+08+*#'(+5# Cross-section +5%#*+01(7(:%&

No electrical contact between wedge and U-profile No bonding at joint with the with the bus on at least 1 side of the joint U-profile and the wedge

Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 35 23/03/2009 LHC status and commissioning 4

LHC: Facts & Figures

Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 36 Current Plans for Startup

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5K [S. Myers, Talk at ATLAS Collaboration Meeting, October 5, 2009] Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 37

Current Plans for Startup

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?& [S. Myers, Talk at ATLAS Collaboration Meeting, October 5, 2009] Probing the High Energy Frontier at the LHC, U Heidelberg, Winter Semester 09/10, Lecture 1 38