LHC Upgrades and Other Future Options XXII Nordic

LHC Upgrades and Other Future Options XXII Nordic Conference on Particle Physics, Skeikampen 2012 Albert De Roeck CERN, Geneva, Switzerland Antwerp University Belgium Davis University USA January 6 2012 1

Today: Epiphany Day! Suitable day to have a look at the future! 2

Contents • Introduction: LHC today and towards 2020 • Luminosity upgrade scenario for the LHC machine – High Luminosity: HL-LHC – Higher Energy: HE-LHC – Electron–proton LHe. C • Physics case • Planned detector upgrades • Other Future Options • Summary Note: Very little specific physics studies for the first two options since 2002. Recently: some specific performance studies for the detector upgrades 3

The LHC: 28 Years Already! 2004 1984 /LHC 1984: cms energy Luminosity 1987: cms energy Luminosity Final: cms energy Luminosity 10 -18 Te. V 1031 -1033 cm-2 s-1 16 Te. V 1033 -1034 cm-2 s-1 (7) 14 Te. V 1033 -1034 cm-2 s-14

LHC Recent History/Schedule 10 -20 fb-1 PHASE 0 PHASE II 5

LHC Performance in 2011 6

LHC Performance in 2011: Records 7

LHC proton-proton Run 2011

The LHC: What to expect in 2012? F. Zimmerman 9

Projected LHC Performance in 2012 S. Myers Expect ~ 10 fb-1 with 25 ns 10

Electron Cloud Effect • Electrons from gas molecules, ionized by the proton bunch & synchrotron radiation. • Once released, electrons get accelerated to 100 -1000 e. V and hit the wall surface heating Can be preventive to run with to short bunch spacing Shown to be an issue in LHC operation 11

The LHC Plan up to 2021 Plans have been adapted on ‘yearly basis’ so far 12

Expected LHC performance 13

Projected LHC Performance in 2015 14

Projected LHC Performance in 2015 Alternatively 15

Projected LHC Performance till 2021 16

Projected LHC Performance till 2021 17

Upgrades of the LHC (2003 view) hypothetical luminosity scenario J. Strait 2003: Not an “official” LHC plot Statistical error 1/ N error/2 N N. 4 Constant luminosity/year 1 year 4 years 16 years Luminosity= #events/cross-section/time At the point the design luminosity is reached: 1034 cm-2 s-1 then After ~3 -4 years the simple continuation becomes less exciting Time for an upgrade? 18

The LHC upgrade Two options have been discussed/studied (since ~ 2002) • Higher luminosity ~1035 cm-2 s-1 (SLHC, now called HL-LHC) –Needs changes of the machine and particularly of the detectors Start change to LE-LHC mode after 2021 Collect ~2500 fb-1/experiment in ~7 -8 years data taking. • Higher energy? (DLHC, now called HE-LHC) – s of 28/33 Te. V needs ~17/20 T magnets R&D needed! –Even ideas on increasing the energy by factor 3 (P. Mc. Intyre) Run I s Run II s Int Lumi (run I) Int. Lumi (final) Tevatron 1. 8 Te. V 1. 96 Te. V 100 pb ~10 -12 fb HERA 300 Ge. V 320 Ge. V 100 pb ~500 pb 19

HL-LHC – LHC modifications IR upgrade(detectors, low-b quad’s, crab cavities, etc) ~2022 F. Zimmerman SPS enhancements (anti e-cloud coating, RF, impedance), 2012 -2022 Linac 4, ~2014 Booster energy upgrade 1. 4 → 2 Ge. V, ~2014 or RCS

LH-LHC Targets (2011) 21

Example Parameters 22

Luminosity Leveling 23

Luminosity leveling with beam-beam offset for LHCb The luminosity can be successfully leveled using transverse offsets between 0 and a few s (here at IP 8) without significant effects on the beam or the performance of the other experiments (IP 1&5)

Event Pile-up!! 0. 2 events/crossing, 25 ns spacing 19 events/crossing, 25 ns spacing 2 events/crossing, 25 ns spacing 100 events/crossing, 25 ns spacing Luminosity leveling pt > 1 Ge. V/c cut, i. e. all soft tracks removed

Higher Energies Thanks to James Stirling 26

HE-LHC – LHC modifications HE-LHC 2030 -33 SPS+, 1. 3 Te. V, 2030 -33 2 -Ge. V Booster Linac 4

HE-LHC 28

LHC Upgrade Planning 29

Linac 4 Construction Started 30

Physics Studies for the LHC upgrade • Electroweak Physics Examples studied • Production of multiple gauge bosons (n. V 3) in some detail • triple and quartic gauge boson couplings • Top quarks/rare decays • Higgs physics • Rare decay modes • Higgs couplings to fermions and bosons • Higgs self-couplings • Heavy Higgs bosons of the MSSM • Supersymmetry • Extra Dimensions Include pile up, detector… • Direct graviton production in ADD models • Resonance production in Randall-Sundrum models Te. V-1 scale models • Black Hole production • Quark substructure hep-ph/0204087 • Strongly-coupled vector boson system • WLZL g WLZL , ZLZL scalar resonance, W+LW + L • New Gauge Bosons 10 years already!!! 31

SUSY Reach: LHC, HL-LHC & HE-LHC Impact of the HL-LHC Extend the discovery region for squarks and gluinos by roughly 0. 5 Te. V, i. e. from ~2. 5 Te. V 3 Te. V 5 contours CMS This extension involved high ET jets/leptons and large missing ET Not much compromised by increased pile-up at HL-LHC (? ) m 1/2 universal gaugino mass at GUT scale m 0: universal scalar mass at GUT scale tan =10

HL-LHC: tackle difficult SUSY scenarios Squarks: 2. 0 -2. 4 Te. V Gluino: 2. 5 Te. V Can discover the squarks at the LHC but cannot really study them PT >700 Ge. V & ETmiss > 600 Ge. V eg. Benchmark Point K in hep-ph/0306219 m 1/2=1300 Ge. V, m 0=1000 Ge. V, tanβ=35 signal Inclusive: Meff > 4000 Ge. V S/B = 500/100 (3000 fb-1) Exclusive channel ~~ qq 10 10 qq S/B =120/30 (3000 fb-1) Higgs in 2 decay 2 1 h becomes visible at 3000 fb-1 Measurements of some difficult scenarios become possible at the HL-LHC

HL-LHC: tackle difficult SUSY scenarios all events 3000 fb-1 Dilepton edge! Point K: m(squark, gluino) > 2 Te. V regime with quasi stable stau 7 < t < 20 nsec red: same flavor leptons, blue: different flavors; shaded: SM bkgd SLHC 3000 fb-1 h bb signal K, H just indicative! SM bkgd High momentum leptons, but lot of stat needed to reconstruct sparticle mass peaks from edge regions! SLHC luminosity should be crucial, but also need for jets, b-tagging, missing Et i. e. adequate detector performances (calorimetry, tracker) to really exploit the potential of increased statistics at SLHC…. . 34

The Higgs at the LHC • First step – Discover a new Higgs-like particle at the LHC, or exclude its existence • Second step – Measure properties of the new particle • Measure the Higgs mass • Measure the Higgs width • Is there more than one Higgs? • Measure cross sections x branching ratios LH-LHC • Ratios of couplings to particles (~mparticle) added • Measure decays with small/dificult branching ratios (e. g H ) value • Measure CP and spin quantum numbers • Measure the Higgs self-coupling (H HH), in order to reconstruct the Higgs potential? 35

Higgs Decays Modes Rare Higgs Decays g. H /g. H ? Channels studied: H Z �� H g. Hff Branching ratio ~ 10 -4 for these channels! Cross section ~ few fb Channel m. H H Z �� ~ 140 Ge. V H 130 Ge. V S/ B LHC (600 fb-1) ~ 3. 5 (gg+VBF) S/ B SLHC (6000 fb-1) ~ 11 ~ 9. 5 (gg) Higgs Couplings (ratios) Can be improved with a factor of 2: 20% 10% at HL-LHC 36

Higgs Self Coupling Measurements Once the Higgs particle is found, try to reconstruct the Higgs potential ~ v m. H 2 = 2 v 2 Djouadi et al. Dawson et al. /2 < < 3 /2 Difficult/impossible at the LHC 37

Higgs Self Coupling Baur, Plehn, Rainwater jj � jj HH W+ W- � Limits achievable at the 95% CL. for =( - SM)/ SM LHC: = 0 can be excluded at 95% CL. HL-LHC: can be determined to 20 -30% (95% CL) Note 1: Different conclusion from ATLAS study no sensitivity at LHC and smaller sensitivity At HL-LHC. Jury is still out Note 2: Does not work for low Mass Higgs (ie below 150 Ge. V) This needs revisiting… 38

Higgs Self Coupling for low MH Baur, Plehn, Rainwater hep-ph/0310056 mvis pp bbbb not useable pp bb difficult pp bb not useable pp bb promising For m. H=120 Ge. V and 600 fb-1 expect 6 events at the LHC with S/B~ 2 (single b tag) Interesting measurement at the LE-LHC (double b tag) Needs accurate prediction of the bb background rate Needs detector simulation 39

SUSY Higgs Particles: h, H, A, H Dominated in the green wedge by signal/background. Increase in statistics helps!! In the green region only SM-like h observable with 300 fb-1/exp Red line: extension with 3000 fb-1/exp Blue line: 95% excl. with 3000 fb-1/exp Heavy Higgs reach increased by ~100 Ge. V at the HL-LHC. 40

SLHC: KK Gravitons Randall Sundrum model Predicts KK graviton resonances k= curvature of the 5 -dim. Space m 1 = mass of the first KK state Te. V scale ED’s KK excitations of the , Z T. Rizzo HL-LHC 95% excl. limits 1000 fb-1: Increase in reach by 25% Direct: LHC/600 fb-1 6 Te. V LH-LHC/6000 fb-1 7. 7 Te. V Interf: LH-LHC/6000 fb-1 20 Te. V 41

HL-LHC: New Z’ Gauge Bosons with Z-like couplings S. Godfrey Includes pile-up, ECAL saturation… Reach: LHC/600 fb-1 HL-LHC/6000 fb-1 HE-LHC/600 fb-1 5. 3 Te. V 6. 5 Te. V 8 Te. V 42

Spin Analysis (Z’ Randall Sundrum gravitons) Luminosity required to discriminate a spin-1 from spin-2 hypothesis at the 2 level Needs statistics! May well be a case for the HL-LHC Also: SUSY particle spin analysis (Barr, Webber, Smiley) need > 100 fb-1 43

Z’ Studies and Searches T. Rizzo Eg Z’ detailed studies will likely require very high luminosities 44

Extra Dimension Signals at the LHC Graviton production! Graviton escapes detection example escape! Large (ADD) type of Extra Dimensions Signal: single jet + large missing ET About 25% increase in reach 45

Compositeness : contact interactions qq Deviation from SM 2 -jet events: expect excess of high-ET centrally produced jets. 95% CL (Te. V) 14 Te. V 300 fb-1 40 28 Te. V 3000 fb-1 mjj > 11 Te. V * angle btw jet & beam If contact interactions excess at low 14 Te. V 3000 fb-1 60 28 Te. V 3000 fb-1 85 46

Strongly Coupled Vector Boson System If no Higgs, expect strong VLVL scattering (resonant or non-resonant) at ~ 1 Te. V q q q VL VL VL q VL Could well be difficult at LHC. What about HL-LHC? • degradation of fwd jet tag and central jet veto due to huge pile-up • BUT : factor ~ 10 in statistics 5 -8 excess in W+L scattering other low-rate channels accessible 47

WZ Resonances in Vector Boson Scattering Vector resonance (ρ-like) in WLZL scattering from Chiral Lagrangian model M = 1. 5 Te. V 300 fb-1 (LHC) vs 3000 fb-1 (SLHC) lepton cuts: pt 1 > 150 Ge. V, pt 2 > 100 Ge. V, pt 3 > 50 Ge. V; Etmiss > 75 Ge. V At LHC: S = 6. 6 events, B = 2. 2 events At HL-LHC: S/ B ~ 10 These studies require both forward jet tagging and central jet vetoing! Expected (degraded) HL-LHC performance is included 48

Top Quark Properties HL-LHC statistics can still help for rare decays searches t q. Z Results in units of 10 -5 Ideal = MC 4 -vector Real = B-tagging/cuts as for 1034 cm-2 s-1 -tag = assume only B-tag with muons works at 1035 cm-2 s-1 Can reach sensitivity down to ~10 -6 BUT vertex b-tag a must at 1035 cm-2 s-1 49

Triple/Quartic Gauge Couplings 50

Detectors for HL-LHC (2003) 51

Detector Upgrades: Examples Phase 0 & I Pixel detectors Hadron calorimeters Muon detectors Trigger, DAQ Phase II New trackers Trigger, DAQ… Phase-0, I upgrades. Phase-II upgrades (high lumi) still in design 52

CMS Planned Upgrades 53

ATLAS Planned Upgrades Also LHCb: New Front-end Electronics all detectors /Trackers ALICE: Faster TPC gas/DAQ/trigger/muon tracker extension/ITS… 54

Comment: Detectors for HL-LHC • Many developments ongoing based on generic New Physics Ideas and general detector improvements. Starting already in 2013. • Would be useful also to prepare for special cases Examples: – Forward tracking (up to η~5). Useful eg for top asymmetry measurements – Timing to 100 ps level. Useful for heavy stable charged particles – Tracking (trigger) for long lived particles –… 55

The Future?

Next Accelerator: A Linear e+e- Collider? Luminosity ~ 2 1034 cm-2 s-1 ~31 km 500 Ge. V TDR under preparation for 2013 Technology essentially ready Luminosity ~6 1034 cm-2 s-1 ~40 km 3 Te. V CDR completed (Feb 2012) Technology still in R&D Discussion at the European Strategy Meeting September 2012 (Krakow) 57

Higgs studies at an e+e- linear Collider Can detect the Higgs via the recoil to the Z Fully simulated+reconstructed HZ event Very clean compared to events at LHC Precision measurements! Observation of the Higgs independent of decay modes Precise determination of couplings 58

A LC is a Precision Instrument • Clean e+e- (polarized intial state, controllable s for hard scattering) • Detailed study of the properties of Higgs particles mass to 0. 03%, couplings to 1 -3%, spin & CP structure, total width (6%) factor 2 -5 better than LHC/measure couplings in model indep. way • Precision measurements of SUSY particles properties, i. e. slepton masses to better than 1%, if within reach • Precision measurements a la LEP (TGC’s, Top and W mass) • Large indirect sensitivity to new phenomena (eg WLWL scattering) LC could play an important role to disentangle the underlying new theory 59

CLIC: Overview of Physics Reach MH=900 Ge. V New Z’ resonance Heavy Higgs s=5 s=3 ADD Extra Dimensions Measuring the Higgs self coupling to 5 -10% 60

Indicative Physics Reach Ellis, Gianotti, ADR hep-ex/0112004+ few updates Units are Te. V (except WLWL reach) Ldt correspond to 1 year of running at nominal luminosity for 1 experiment PROCESS Squarks WLWL Z’ Extra-dim ( =2) q* Lcompositeness TGC ( ) LHC 14 Te. V 100 fb-1 2. 5 2 5 9 6. 5 30 0. 0014 HL-LHC HE-LHC VLHC ILC CLIC 14 Te. V 28 Te. V 40 Te. V 200 Te. V 0. 8 Te. V 5 Te. V 1000 fb-1 100 fb-1 500 fb-1 1000 fb-1 3 4 6 12 7. 5 40 0. 0006 † indirect reach (from precision measurements) 4 4. 5 8 15 9. 5 40 0. 0008 5 7 11 25 13 50 20 18 35 65 75 100 0. 0003 0. 4 6 8† 5 -8. 5† 0. 8 100 0. 0004 2. 5 90 30† 30 -55† 5 400 0. 00008 Approximate mass reach machines: s = 14 Te. V, L=1034 (LHC) : up to 6. 5 Te. V s = 14 Te. V, L=1035 (HL-LHC): up to 8 Te. V s = 28 Te. V, L=1034 : up to 10 Te. V 61

Large Hadron electron Collider RR LHe. C: 2020 -21, new ring in LHC tunnel, with bypasses around experiments LR LHe. C: 2020 -21, recirculating linac with energy recovery RR LHe. C e-/e+ injector 2020 -21, 10 Ge. V, 10 min. filling time

LHe. C Parameters 63

Physics Program CDR 530 pages αs to 0. 1% precision Leptoquarks & leptogluons, excited electrons, contact interactions, 4 th lepton family, Z’, quark substructure, extra dimensions, diquarks, Higgs CP studies… Very little (so far) on SUSY; only RPV SUSY 64

Leptoquark Studies 65

Contact Interaction Studies 66

LEP 3? What if the Higgs is 120 -125 Ge. V? Do we need a Linear Collider for a Higgs factory? A. Blondel and F. Zimmerman: LEP 3? ar. Xiv: 1112. 2518 v 1 Proposal: Reinstall an e+e- collider in the LHC tunnel With LC RF to make up for the energy loss of 7 Ge. V for a 120 Ge. V/beam Note: beam lifetime ~ 12 minutes. Needs top-up ring Expected Higgs events ~ 20 K/year Also mentioned DLEP: a 52 km tunnel nearby CERN? 67

A Fixed Target Expe. Riment (AFTER)? JP Lansberg et al. Use crystals, brought to 7σ of the beam, to extract protons or ions for a fixed target experiment. Runs parasitically on the collider A QCD experiment for 2020+ ? 68

Summary • Detector upgrade preparations in the experiments are well under way, making use of 3 foreseen long shutdowns. • HL-LHC: High Luminosity operation expected to start around 2022. Expect ~ 3 ab-1/exp or more by 2030. • HE-LHC: CM Energy discussed now 33 Te. V, but magnets still in R&D. Not starting before well into the 2030’s, according to present planning. . . • LHe. C: Technically feasible. CDR in review • Physics case for the HL-LHC and HE-LHC have not been revisited since quite some time. Maybe something to think about for 2013 -14… 69