1 LHCb Upgrade: Flavour Physics at High Luminosity Chris Parkes EPS HEP Conference, Manchester, Detector Session, July 21 st 2007 LHCb - Aims for first phase (~2013) SuperLHCb physics – Probing New Physics Technology - Vertex Trigger, Radiation Level Conclusion- Forward Plan Thanks to LHCb collaborators, notably: Hans Dijkstra, Jim Libby, Franz Muheim, Guy Wilkinson,

2 p p 250 mrad 10 mrad Dedicated B System CP Violation & Rare Decay Experiment Full spectrum of B hadrons: B s system, All angles, sides of both CKM  s Lots of events !

3 LHCb Construction on Schedule Muon Calorimeters RICH2 Trackers Magnet RICH1 VELO

4 LHCb Goals - First Phase 10 fb -1 First observation of very rare decay B s mixing phase Unitarity Triangle Spectacular progress in heavy flavour physics: –Baseline measurement A CP (J/  K S ) –B s Oscillations Measurement, Charm results Impressive range of additional measurements Flavour Physics Progress at 0.01 rad B  DK Bs  DsK B(s)  h+h− exploiting U-spin γ at few degrees Today 10 fb -1 LHCb + lattice

5 LHCb Physics Programme But NOT Limited by LHC Limited by Detector Upgrade to extend Physics reach –Exploit advances in detector technology –Radiation Hard Vertex Detector –Displaced Vertex Trigger –Better utilise LHC capabilities Timescale, 2015 Collect ~100 fb -1 data Modest cost compared with existing accelerator infrastructure Independent of LHC upgrade SLHC not needed But compatible with SLHC phase

6 Upgrade Physics Programme Examples CP Violation –Angle  to better than 1 0 –Tree Diagram Dominated Decays, <<1 0 theory –Gluonic Penguins B d  K 0 Complementary to ATLAS / CMS direct searches New particles are discovered LHCb measure flavour couplings through loop diagrams No new particles are found LHCb probe NP at multi-TeV energy scale Angular Correlations - Not just A fb Rare Decays Charm Physics Mixing studies in D 0 →hh CPV searches Rare decays, eg. D (0) (s) →l + l - [(Xu,s)] LHCb 2 fb -1 superimposed

7 B s mixing phase Upgrade can achieve 10% measurement of SM Also measure from loops - penguin dominated  = New Physics ! Standard LHCb 1 Year CDF  ms Little Higgs Model Blanke & Buras [hep-ph/ ] SM Ligeti et al. [hep-ph/ ]

8 Initial Phase of LHCb Operations Data taking starts 2008 Defocus LHC beams LHCb L= 2x10 32 cm -2 s -1 Factor 50 below ATLAS/CMS design L Most events have single interaction Displaced Vertex trigger 2nd level of triggering Multiple Interactions Limit Triggering rate of pp interactions LHCb Upgrade L= 2x10 33 cm -2 s -1 Cope with 4 int./x-ing SLHC peak L= 8×10 34 cm -2 s -1 Baseline - 40MHz, alternate High, Low I H L LHCb GPDs HH Effective 20MHz Crossing rate Select Low I for desired luminosity

9 LHCb Trigger System Cope with 4 interactions / beam crossing Existing 1 st Level Trigger 1MHz readout Veto on multiple interactions Existing Trigger based on: High p T Muons Calorimeter Clusters Events with muons – trigger efficient Events with hadrons – need improved trigger Require Displaced Vertex Trigger At 1 st level Current 1 st Level Trigger Performance

10 Trigger Gains – 40 MHz readout Improve efficiency for hadrons and photons –ε Trig (B→hadronic) ~ 25-35% –ε Trig (B→γX) ~ 30-40% –ε Trig (B→μμX) ~ 60-70% Higher Level Trigger –Only limitations CPU Algorithmic Ingenuity –(Former) improves with Moore’s Law

11 Radiation Hard Vertex Locator Upgrade Requires high radiation tolerance device > MeV neutron eq /cm 2 Strixels / Pixels –n-on-p, MCz, 3D Z Beam 8cm VELO Module Active Silicon only 8mm from LHC beam Pixel layout x z 390 mrad 60 mrad 15 mrad 1 m x y

12 LHCb Upgrade Baseline & Issues Trigger in CPU Farm –Event building at 40 MHZ, CPU power OK –Hadron efficiency ~ factor two improvement Read-out all detector 40MHz –Replace all FE Electronics Vertex locator, Silicon Tracker, RICH HPD, Outer Tracker FE, Calorimeter FE boards Radiation Damage –Need to replace Velo anyway –Inner part of Shashlik Calorimeter –Inner part of silicon tracker –Remove muon chamber before Calorimeter Occupancy –Inner part of outer tracker, 6%  25% Increase silicon coverage (faster gas, scintillating fibres) –Tracking algorithms for higher occupancy Inner / Outer Tracker PWO crystals ECAL

13 Major Physics Programme at modest cost –Flavour Sector of New Physics –  s measurement –Precision  Critical Technology –Radiation Hard Vertex Detector –With Displaced Vertex Trigger Compatible with but independent of SLHC Upgrade Summary ?? ? ? LHCb preparation in good shape Looking forward to first data And an even brighter far future Lowry Upgrade

14 University of Glasgow, Scotland 1 st - 5 th September 2008 The conference explores the scientific and technical developments of detector systems used in: Astronomy and space science; Astrophysics; Condensed matter studies; Industrial applications; Life sciences; Medical physics; Nuclear Physics, Particle physics and Synchrotron based science. National Organising Committee (subject to change) P.P. Allport, Liverpool R.L. Bates, Glasgow A.J. Bird, Southampton C.R. Cunningham, UK ATC, Edinburgh G.E. Derbyshire, STFC, RAL P. Evans, ICR, London R. Farrow, STFC, Daresbury W. Faruqi, MRC, Cambridge M. Grande, Aberystwyth P.R. Hobson, Brunel D.P. Langstaff, Aberystwyth P.J. Nolan, Liverpool D.J. Parker, Birmingham P.J. Sellin, Surrey A. Smith, MSSL, London R. Speller, UCL, London T.J. Sumner, IC, London S. Watts, Manchester

15 Backup

16 Extrapolating to 100 fb -1 Only consider strategies which are theoretically clean Critically reliant on Trigger Upgrade  B s →D s K: statistical scaling leads to 1° uncertainty for 100 fb -1  B  D(K s ππ)K : statistical scaling leads to 1.2 ° for 100 fb -1  Other modes B  D(K s Kπ)K, B  D(K s KK)K and 4-body to be exploited  B  D(hh)K : ADS/GLW methods statistics huge but will need global fit including additional information to overconstrain Toward a sub-degree error on  LHCb (10 fb -1 ) Super-LHCb (100 fb -1 ) Super Flavour Factory (75 ab -1 ) D s K27 k540k- D(K s ππ)K≤25k0.5M80k D(Kπ) fav K280k5.6M131k Extrapolations from published B-factory analyses

17 B  K * μμ A FB 0 point is not enough: –SLHCb σ s0 /s 0 =2.1% –Exclusive NLO theory today σ s0 /s 0 =9% –improve by 2020 Transversity angle asymmetry analysis extremely promising –Probes chiral structure (c.f. TDCPV B  K * γ) –Theoretically clean –Will benefit greatly from SLHCb statistics LHCb 2 fb -1 superposed Kruger and Matias, Phys.Rev.D71:094009, 2005

18 Charm physics If charm mixing has indeed been observed, what next ? Precise measurements of x (‘) and y (‘) Search for (and detailed study) of CPV in charm – v. promising for NP Recent detailed simulation studies at LHCb show great promise in D 0 →hh decays. After all selection cuts yield from B decays alone is expected to be times (10 fb -1 ) that of total from B-factories (2 ab -1 ). Target charm analyses at LHCb and SLHCb (diverse programme!): Mixing studies in D 0 →hh CPV search in partial width differences in D 0 →KK, ππ (SCS) CPV search in D + →K - ππ Dalitz (SCS) Mixing and CPV in D 0 →K s ππ Dalitz Mixing and CPV in D 0 →K + πππ (DCS) CPV search in T-odd moment & amplitude analysis of D 0 →KKππ (SCS) Rare decays, eg. D (0) (s) →l + l - [(Xu,s)] Will benefit from change of trigger strategy at SLHCB

19 CPV in gluonic penguin One of the poster children of a SFF –For good reason given the tantalising hints of a discrepancy with sin2  from b  ccs Concentrate on the cleanest modes B d  K 0,ηK 0 and K 0 K 0 K 0 –Average discrepancy 0.10±0.06 No attempt to add theory –5σ with current central value an important goal B d  K 0 most promising at current LHCb –Precision at end of LHCb 0.14 –End of SLHCb 0.03 assuming 2×ε trigger same as SFF but they have the other important modes…..

20 B s →  B s analogue of B d  K 0,η K 0 etc Dependence on V ts in both the decay and B s mixing amplitudes leads to the SM CPV being < 1% –for example M. Raidal, PRL 89, (2002) P  VV decay requires full angular analysis to extract CP info Simulation studies with background and detector effects –2000 (4000) events/fb (S)LHCb –NP phase sensitivity of at current LHCb –SLHCb sensitivity (0.5°)

21 Mixing phases-the systematic frontier sin2  improvement can be made with control channel measurements of penguin pollution and tagging –B s  J/ψK 0 S R. Fleischer, Eur. Phys. J. C. 10., 299 (1999) –Push toward 1%/0.2° uncertainty 8% relative uncertainty on SM- like B s mixing phase from B s  J/ ψ  possible at SLHCb –Matches current indirect determination –Direct proportionality to η leads to interesting constraint on UT // to that from K L  π 0 νν –Penguin control possible from B s  J / ψρ (Super- )LHCb 2 fb fb fb -1 σ (stat) Superposed on LHCb 10 fb -1 + lattice

22 B s(d)  μμ 5σ observation expected at current LHCb even if value of BF is SM Theory prediction already at ~10% More precise determination at SLHCb would be constraining of NP models with large tan  –c.f. B  K * μμ transversity analysis constrains small tan  B s  μμ/B d  μμ = 32.4 ± 1.9 tightly constrained in SM and MFV –one of the magic numbers of CMFV (Buras) Matching theory precision is impossible with 100 fb -1 –But observation possible at SLHCb as long PID can cope with double punch-through background from B d  ππ –Maybe SLHC GPDs???? Or UltraLHCb!

23 LHCb high luminosity running L= 2x10 33 cm -2 s -1 e + e - Super B-Factory –Linear Super-B (Frascati) –Super-Belle Super B Factories 100 fb -1, ab -1, 2020 Complementarity B s – LHCb Upgrade Neutrals – e + e - B d - overlap LHCb upgrade B s Lower cost No new accelerator BsBs Common No IP Neutrals,

24 Detector Upgrade Critical component to achieve this physics Radiation Hard Vertex Detector with Displaced Vertex Trigger VElo Superior Performance Apparatus

25 Maximum Fluence NIEL 1 MeV n eq /cm 2 /year Strongly non-uniform dependence on 1/r 2 and station (z) Middle station Far station Extreme Radiation Environment LHCb VELO will be HOT! VESPA needs > n eq /cm 2 charged particle tolerance

26 Radiation Hard Technologies Active UK Technology R&D for LHC upgrades Applicable to strixels & pixels Extreme rad. hard 3D Czochralski n-on-p

27 Schedule & Costing Schedule –R&D underway Velo/Vespa Testbeam in Autumn ’08 Exploit commonality with GPDs on Electronics –2010 decision on upgrade instrumentation – upgrade detector during planned SLHC upgrade – gather 100 fb -1 Cost –Front-end electronics replacement estimate 12 M€ –Detailed costing not available till after R&D phase –Anticipated hardware cost ~ 45 M€