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INFN Roadmap WG “Upgrade di luminosità di LHC” (SLHC)

INFN Roadmap WG “Upgrade di luminosità di LHC” (SLHC). Convener: M. de Palma. Out line. Participants Physics issues Detectors point of view ( limited to those in which INFN is involved ) Conclusion and question to WG NB: WG have still not looked at trigger, DAQ and costs. Participants.

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INFN Roadmap WG “Upgrade di luminosità di LHC” (SLHC)

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  1. INFN RoadmapWG “Upgrade di luminosità di LHC” (SLHC) Convener: M. de Palma

  2. Out line • Participants • Physics issues • Detectors point of view (limited to those in which INFN is involved) • Conclusion and question to WG NB: WG have still not looked at trigger, DAQ and costs. M de Palma, WG SLHC

  3. Participants • Theorist: Frixione,Colangelo • Atlas:Laurelli, Dardo, Meroni, (ID), Citterio, Costa (ECAL), Del Prete (Hcal), Bagnaia, Nisati, Primavera (MU), DiCiaccio, Veneziano (Trigger) • CMS:Messineo, Palla, Bisello (Tracker), Pastrone, Ragazzi (ECAL), Dalla Valle, Paoloucci, Zotto (MU) • LHCb: Bencivenni(Tracker), Lai(Elet.), Marconi(Trigger) + all expert and volounteers………. First meetings held the 17 Oct. and 14 Nov. Next meeting 24 Nov. M de Palma, WG SLHC

  4. Physics issues • Two (obvious) caveats: • The physics program of a luminosity upgraded SLHC will be mainly determined by the discoveries and the experience collected at LHC in a few years of running • Discussion is based on existing studies (starting point for subsequent work) There hasn't been much of theoretical activity recently specially devoted to SLHC. There is of course a lot of work done for LHC, which will be fine for SLHC as well. Main reference: SLHC physics and detectors: F. Gianotti et al., Eur. J. Phys. C 39 (2005) 293 M de Palma, WG SLHC

  5. LHC SLHC s 14 TeV 14 TeV L 1034 1035 Bunch spacing t 25 ns 12.5 ns * pp (inelastic) ~ 80 mb ~ 80 mb N. interactions/x-ing ~ 20 ~ 100 (N=L pp t) dNch/d per x-ing ~ 150 ~ 750 <ET> charg. particles ~ 450 MeV ~ 450 MeV Tracker occupancy 1 5/10 Pile-up noise in calo 1 ~3 Dose central region 1 10 Scenario M de Palma, WG SLHC

  6. Physics motivation Tanks to S. Frixione and P. Colangelo Tests of the SM:Multiple gauge boson production Triple gauge couplings  Higgs physics:Higgs pair production and trilinear coupling  Couplings to bosons and fermions Rare Higgs decays Scattering of VB: ( i.e. new strong interaction regime)  Susy:Heavy Higgs bosons of MSSM  SUSY particle reach  Exotica: Heavy gauge bosons  Quark compositeness Extra-dimensions M de Palma, WG SLHC

  7. Triple gauge boson couplings (I) Three- and (four) -vector-boson couplings are a direct consequence of the non-abelian gauge structure of the SM. In the SM they are uniquely fixed, extensions to SM induce deviations (form factors are introduced ->  scale of new physics) LHC favourable channels : W ℓ WZ  ℓ ℓ ℓ Expected sensitivity to TGC, 95% CL constraints, ATLAS 5 parameters introduced to describe TGCs:g1Z (1 in SM),kz, k, , z(0 in SM)W  probes k ,  andWZ probes g1z, kz, z M de Palma, WG SLHC

  8.  DkZ Z Z Triple gauge boson couplings (II) Correlations among parameters 14 TeV 100 fb-1  LHC 28 TeV 100 fb-1 14 TeV 1000 fb-1  SLHC 28 TeV 1000 fb-1 SLHC improves LHC results by at least 50% M de Palma, WG SLHC

  9. Higgs pair production and self coupling (I) Two Higgs radiated independently (from VB, top) and trilinear self-coupling terms proportional to HHHSM. Higgs self-interactions fully determined in the SM after fixing mHTests of SM EWSB sector qq -> qqVV -> qqHH qq ->VHH very small cross sections, hopeless at LHC (1034), hope at SLHC M de Palma, WG SLHC

  10. Higgs pair production and self coupling (II) ATLAS: preliminary study for SLHC (1035 cm-2 s-1)  a first measurement of HHHis possible (170 < mH < 200 GeV)better than 25%. gg  HH  W+ W– W+ W–  ℓ±jjℓ±jj with same-sign dileptons Cross sections for Higgs boson pair production in various production mechanisms and sensitivity to HHH. Arrows correspond to variations of λHHH from 1/2 to 3/2 of its SM value Probably a strongest physics case for SLHC A delicate counting experiment: background control essential M de Palma, WG SLHC

  11. S V Scattering of vector bosons • If no (light) Higgs, anomalies should appear in VB scattering: • deviations in WW scattering • resonance production This should be a possible onset of a new strong interaction regime Vector resonance (r-like) in WLZL scattering from Chiral Lagrangian (BESS) model Scalar resonance in WL WL, ZL ZL -> ZL ZL scattering (BESS model) Preliminary results indicate that these should be observable at SLHC, but not at LHC  A “discovery" at SLHC A counting experiment; good background knowledge mandatory Detectors must have good jet-tagging and jet-veto capabilities M de Palma, WG SLHC

  12. Heavy Higgs bosons of MSSM The MSSM features a rich Higgs sector (h;H; A;H). The discovery of its heavy part could be beyond reach at LHC for large mA green: region whereonly one (the h, SM-like)among the 5 MSSM Higgs bosons can be found (assuming SM decay modes) LHC 300 fb-1 SLHC 3000 fb-1 A 95% C.L.exclusion boundary is a further ~50 - 100 GeV to the right of the discovery boundary MSSM parameter space regions for > 5  discovery for the various Higgs bosons (both experiments combined) M de Palma, WG SLHC

  13. 5-discovery countours SLHC LHC SUSY particle reach Higher integrated luminosity  obvious increase in mass reach in searches SLHC improves LHC reach for up to 0.5 TeV (to ~ 3 TeV in mass) with inclusive searches. But this is just “ the reach”: the main advantage of increased statistics should be in the sparticle spectrum reconstruction possibilities. Some exclusive searches be come possible at SLHC But for decay studies good detector performances are needed: lepton, jets, Emiss, b-tagging…… M de Palma, WG SLHC

  14. Heavy gauge bosons Additional heavy gauge bosons (W,Z-like) are expected in various extensions of the SM symmetry group (LR,E6,SO10…..), with couplings to leptons ~ similar to SM W,Z Ex. sequential Z’ model Z’ production and Z’ width (assuming same BR as for ZSM) For high mass objects electrons more usefull than muons - thanks to better resolution Expected backgrounds from Drell-Yan and tt production at the few % level With 10 events to claim discovery, reach improves from 5.3 TeV at LHC to 6.5 TeV at SLHC M de Palma, WG SLHC

  15. LHC luminosity profile vs physic cases cm-2s-1  De Negri M de Palma, WG SLHC

  16. Physics summary • Significantly increased physics reach in all typical LHC physics channels. • These improvements are, at least, better measurements and better exploitation of the LHC energy domain and make the LHC upgrade very attractive and an obvious next M de Palma, WG SLHC

  17. SLHC Scenario • The most relevant SLHC parameter for experimental apparatus are: • (from W. Scandale talk) • BCO interval: (?)25ns, 15ns, 12.5ns, 10ns • Forward area: The closest machine element will be movetowards the IP • Timescales: Assume 2014±2 years • Environment: Increased radiation levels (and resulting activation) • The luminosity will increase as function of time at LHC, we will need to upgrade the detectors in time to take the maximum advantage of this. • We know that some parts of the detector systems might have performance problems or operational problems, and therefore interventions and improvements are require. Issues: Radiation damage Pileups of MB events Bunch spacing and trigger Timing M de Palma, WG SLHC

  18. Basic assumption for detector up-grade • To take advantage of a luminosity increase the detector performance of ATLAS and CMS have to be kept at foreseen actual level ( i.e tracking, b-tagging, vertexing, energy resolution and momentum measurements) • The detector changes have to be “reasonable”. We cannot replace the entire detectors for obvious reasons of cost and time. • One would like to keep as much as possible of the existing large items (calorimeters, muon systems, magnets, cooling, gas, cables, pipes, support structures, movement systems, cryogenic systems, etc). M de Palma, WG SLHC

  19. …… work are already started …… In the experiment; ATLAS: Steering Group established, two workshops in Feb and July 2005. • Plan to organise R&D with Steering Group and Project Office as part of technical coordination to ensure coherence. CMS: Three workshops on SLHC; Feb 2004, July 2004, July 2005. (next Apr 06) • To assist in the R&D project definition, already agreed CMS peer-review scheme. Main lines identified: • Tracker & Trigger • Microelectronics and Power • Optoelectronics & data architectures and ouside experiment ( also inside INFN-G5 programs) • RD50 in the area of radiation hard sensor R&D • Activity on rad-hard electronics • Simulation study • ....and could be that those attivities faster increase with the end of construction tasks of the LCH experiment M de Palma, WG SLHC

  20. SLHC LHC ATLAS - Muon system from P.Bagnaia, L. Nisati MDT Muon system designed with a 5 safety margin on bck rate The detector performance should be Ok with a acceptable degradation of the spatial resolution. The Front-end electronic should be Ok with some problems with high rate but on DAQ side. Also the LV1 electronic should be Ok • If BC < 25 ns • If the trigger decision can be taken on 2 and BCID done al LVL2 Single tube resolution (bck x 5, x 2 worsening for charge fluctuation) M de Palma, WG SLHC

  21. ATLAS - Muon system from A. Di Ciaccio At SLHC additional shielding and beryllium beam pipe should be inserted to further decrease (x 2 reduction) the background rate The expected rate in the Barrel muon system could beestimated ~50-100 Hz/cm2 RPC All along the test (8 ATLAS year, safety factor 5 = 100 Hz/cm2), chamber performance (efficiency, cluster size, rate capability) have remained largely above the actual ATLAS requirements and cover the SLHC request. (provided that Temperature, RH of the environment and gas mixture are kept at a proper value) The detector performance should be OK Since all tests have been done with final Front-end electronic that should be also OK (without safety factor on bkg level) SLHC Few Hz/cm2 500 Hz/cm2 RPC efficiency after 7 ATLAS year M de Palma, WG SLHC

  22. CMS - Muon system from M. Dallavalle MDT The detector performance should be Ok but study on general ageing are still needed. Since chamber will demand higher currents than now available, HV PS system would require some upgrading SLHC would require a full redesign of the trigger and readout electronics, in new technologies to cope with radiation environment, (and to be able to operate at 80 MHz) M de Palma, WG SLHC

  23. CMS - Muon system from P. Paolucci RPC • BARREL: muon rate ~10 Hz/cm2, n and  < 40-50 Hz/cm2 • ENDCAP: muon rate ~10 KHz/cm2, n and  < 10 KHz/cm2 GIF Test on production chamber(equivalent to ~ 15 CMS years) have shown good efficiency and stable current The detector performance should be Ok but without safety margin, more studies needed Front-end work up to 5 MHz  Ok Trigger electronic should be Okbut it is at limit. Situation is very different for End-Cap where even the detector technology is no more adequate M de Palma, WG SLHC

  24. Atlas – LAr Calorimeter from M. Citterio The liquid argon calorimeter was optimized for the nominal LHC luminosity, a x 10 increase of this luminosity would rise concerns on: • Space charge effects → signal reduction • Argon contamination → signal reduction • Charge density increase → pile-up • Activation → noise increase • phase instability →operation problems • Voltage drop in the HT distribution →rate dependent response • General radiation damage of electronics→ single element (now built in 13 different ICs) could not be changed (next slide) • The high occupancy of SLHC require a new read-out chain design • A BC rate > 40 MHz require new pipeline M de Palma, WG SLHC

  25. DMILL AMS Overview of main components on a FEB DSM COTS 128 input signals 32 0T 32 Shaper 32 SCA 16 ADC 8 GainSel 1 MUX 1 fiber to ROD Analog sums to TBB 2 LSB 2 SCAC 1 Config. 1 GLink TTC, SPAC signals 14 pos. Vregs +6 neg. Vregs 2 DCU 7 CLKFO 1 TTCRx 1 SPAC M de Palma, WG SLHC

  26. Atlas – LAr Calorimeter(II) 15 Those affects as expected to be non critical and, since it is impossible to change the detector, we have to survive. More study to drive an optimization strategy are needed. Detector is assumed to be Ok • The HV system will be revisited and HV filter must be redesigned to reduce the rate fluctuation response and noise. 79A complete new architecture of the read-out system is needed. M de Palma, WG SLHC

  27. Atlas -Tile hadron calorimeter from T. Del Prete Detector should be OK A decrease of the light budget produces a degradation of the energy measurement (3-5%) which effects Jet Energy Reconstruction. /E ≈ 10% @1034 ≈ 30% @ 1035for Ejet= 100 GeV All Electronic components have been tested above the rad doses for 10Y @ 1034 . They should survive 5Y @ L = 1035but no NO safety margin. Some part: (Mother Boards, Digitisers, Interface…..)are more rad-fragile If SLHC needs to increase BC rate,all the F/E logic has probably to be redesigned. M de Palma, WG SLHC

  28. CMS – EM Calorimeter from N. Pastrone Crystal The dose in the Barrel ( = 2.4) goes from 0.15 Gy/h @ 1034to 1.5 Gy/h, in the EndCap it reaches 30 Gy/h at  = 2,6 and 75 Gy/h at  = 3. Those produce at SLHC a significant change in LY: <LY> drops by ~25% in barrel, 30% Endcap. In EndCap we are close to the “saturation” condition. Still more study are needed ( irradiation test, calibration study…) LY for different densities of colour centres ( Radiation damage increase colour centres) M de Palma, WG SLHC

  29. CMS – EM Calorimeter (II) Photosensors In Barrel, sensible increase of leakage current (130 A at SLHC) of APD is expected. It translates in large increase in electronic noise ( ~190 MeV per channel with respect to ~ 40 MeV al LHC) (study performance with higher n fluxes) In Endcap, VTP glass window has to be tested at the expected dose. In conclusion: Considering work for disassembly and refurbishing (at least 2 years) and the costs involved, ECAL barrel could be used even with a degradeted performances (to be studied !) due to decrease of LY, increase of noise and pileup. For the Endcap, the situation is more difficult. Read out chain should be OK for BC 2 X 40 MHz M de Palma, WG SLHC

  30. Inner tracking detector General consideration: LHC The limiting factor for the detector lifetime will be radiation damage, which is mainly a function of the integrated luminosity. Assuming 3000 fb-1 at SLHC ( x 6 the integrated luminosity for which currently planned silicon system has been designed) the hadrons fluence and radiation dose at different radius are: SLHC Cumulative effects (NIEL, TID) increase by a factor 5 Instantaneous effects (occupancy, SEU) increase by a factor 10 M de Palma, WG SLHC

  31. Inner tracking detector General considerations: • The silicon sensor, both strip and pixel, would suffer substantial radiation damage strongly degrading the performance. • For the electronic, the situation is somewhat more favourable but similar. • Most of material (frames, glues, insulators… etc.. are not tested to the dose above. • The inner detector system must be completely • rebuilt, both for ATLAS and CMS The bunchtiming should have a strong impact on tracker project, both on sensor and electronic. Shorter Bunch give less occupancy but requires better time resolution…… Information for Atlas came from a 3 days dedicated Workshop (18-20/07/2005) in Genova: http://atu-2005.ge.infn.it/ while the CMS comments presented here are only representative of our present thinking. M de Palma, WG SLHC

  32. Substrate Outer layers, silicon looks promising n+-in-n (as for today pixel), p-type floating zone FZ (50% cheaper, need single side processing) for μstrips Oxygen doped, Magnetic, High resistivity Inner region - no proven alternative to silicon yet - but are other materials possible? Performance Series noise (Cdet) can decrease but parallel (Ileak) may not (Ileak ~ strip length, thickness, particle fluence) Charge collection, high bias voltage (>1000 V), S/N Structure Pixel and pixel 3D, short strips, 2D detectors (stripxel), SS, DS Power dissipation Manufacturability Trackers Sensor Material issues M de Palma, WG SLHC

  33. Very rad-hard electronics Single Event Upset (SEU) will be a serious problems. Technology and design 0.13 µm or smaller CMOS for Pixel, BiCMOS e CMOS per strips: Data rate / opto-links: Power scheme Trigger (with muon system, very appealing but difficult, some ideas from CMS) Trackers Electronic issues M de Palma, WG SLHC

  34. Dimensions sensor size, finer pitch, number of different nodule type,…. Ease of handling and assembly We must minimize handling - could this be done by industry? Should be base units still the Module or Stave or Sector (could high integration give yield problems)? Module construction Integration (still to proof al LHC!) Cost Present design originates in bottom-up approach, underestimates many costs and difficulties Need we approach ! Trackers design issues M de Palma, WG SLHC

  35. ATLAS Tracker,from G. Darbo • Number of layers 8÷11 (most probably 10): • Inner layer: • Pixel, 3÷4 layers, 300÷400 µm x 50 µm, 2.9÷3.7 m2. • Middle layer: • short strips or stripxel, 3÷4 layers, 3.5 cm x 80 µm, 21÷27 m2. • Outer layer: • µstrips, 2÷4 layers, 9 cm x 80 µm, 116 ÷ 327 m2. M de Palma, WG SLHC

  36. CMS Tracker from F. Palla Inner part (R< 60cm)  Pixel layers • Pixel system 1 - 1 layer at radius about 7 cm • Change detector more often (annually) • Improve fluence limit of sensor. Need to study sensors more RD50 activity fundamental research rather than development) • Pixel System 2 - 2 layers at 18 and 22 cm ( need cheaper pixel technology) • Single sided pixel detectors, n+ on p – Silicon (Czochralski) • Large Module size, e.g. 32 x 80 mm sensitive area • Pixel area ~ 160 mm x 650 mm • Pixel System 3 - 3 Layers 30, 40 and 50 cm • Macro pixel detectors of 1 mm x 1 mm/ Micro strips of 200 mm x 5 mm • Simple DC coupled p+ on n – Silicon detector External part ( R> 60cm)  strip layer • Strip System 3-4 Layers fro 60 to 110 cm • About similar to present one M de Palma, WG SLHC

  37. Schedule The WG idea about time: • 2006-2008 General R&D program ( maybe shared with other programs (ILC, -factory, etc…) • 2009-2010 Definition of detector upgrading design within clear SLHC machine project. • 2010-2012 (?) Prototypes, modules “0”, start of construction • 2012- 2015 (?) Construction • 2015(?)- 2017(?) Assembling, integration, commissioning…. • Running M de Palma, WG SLHC

  38. Conclusion • The Inner Detectors will need to be replaced (the actual have been designed for a lifetime of 10 years at 1034). • Ageing and space-charge effects of calorimeters and muon chambers, due to the radiation and activation levels increase, need to be studied in more detail to point out the optimization and/or modifications needed with the goal to change as little as possible. The read-out electronic chain in some case, need to be replaced • Depending on the chosen BCO frequency - the impact on the existing electronics can change significantly. M de Palma, WG SLHC

  39. Questions to WG (I) There is! No competitors are foreseen in the SLHC time scale At moment, all team show interest toward SLHC on the same LHC item Subject of firsts WG meetings, we have reported here ……… • Physics case • Competition and competitivity • Interest of INFN teams involved in LCH exp. to participate ad SLHC: • On same item • On new item • Needed upgrade to the different detectors in both exp. considering the different LHC upgrade scenarios M de Palma, WG SLHC

  40. Questions to WG (II) More detail should be point out in next meetings…….. next meetings ….. at moment, seem yes seem yes • Within the different LHC upgrade scenarios and after the first LHC results when (and how) decide to start: • the dedicate R&D • the experiment upgrade (a later start of dedicate R&D could compromise the detector upgrade) • Within the different LHC upgrade scenarios versus SLC: • The detector up-grade cost • Their share(?) • The dedicated R&D cost • Two experiment remain general purpose experiments. • Still two experiment are needed. M de Palma, WG SLHC

  41. Other physics case M de Palma, WG SLHC

  42. qqHWWqqH ttHttHbb HHZZ HWWHZZ HWWHtt WHWWWHWW Higgs couplings to fermions and bosons Combining different production mechanisms and decay modes get ratios of Higgs couplings to bosons and fermions. Ratios of rates are theory-independent measurements; i.e. are independent form σtotHiggs, ΓH, and Lint. It is mostly statistics limited at LHC therefore should benefit from SLHC luminosity increase  provided detector performances are not significantly reduced. At the SLHC the ratios of Higgs couplings should be measurable with a ~ 10% precision full symbols: LHC (300 fb-1 per exp) open symbols:SLHC (3000 fb-1 per exp) M de Palma, WG SLHC

  43. Multiple gauge boson production Test of high energy behaviour of weak interactions W and Z -> leptons cleanest channel, but the rates are limited at LHC -> SLHC expected numbers of events in purely leptonic final states, 3 and 4 Vector Boson production, SLHC 6000 fb-1 (lepton cuts: pt > 20 GeV, || < 2.5, assumed reconstruction efficiency 90%) WZZ -> 5 leptons, ZZZ -> 6 leptons accessible at SLHC WWWW -> 4 leptons could allow to put limits on 5-ple coupling (zero in SM) M de Palma, WG SLHC

  44. Higgs rare decays • Increased statistics would allow to look for rare decay modes (difficult to observe at LHC). A couple of cases with BR=O(10-4) have been considered. • HSMZℓ+ℓ- • At the LHC (300 fb-1/experiment) signicance is about 3.5  • At the SLHC (3000 fb-1/experiment) signicance is about 11  • HSM+- Impossible to discover at the LHC (significance <3.5) while at LHC expected significance  5s M de Palma, WG SLHC

  45. Compositeness Quarks (and leptons) may be composite structures, bound states of “preons", whose interactions are characterized by a mass scale  Symmetry considerations imply that  > O(1 TeV) • A counting experiment: • deviation in high-pT SM jet production • angular distribution of the jet pairsfrom QCD Effect of compositeness May not be observed at LHC, but evidence at SLHC M de Palma, WG SLHC

  46. Extra-dimensions Theories with extra dimensions lead to expect characteristic new signatures /signals at LHC/SLH. Various models exist and their scales are completely unknown. As a result, an immense spectrum of possibilities opens up in a high-energy regime. Strategies are typically based on (direct or indirect) graviton and/or on Kaluza-Klein excitation searches, and generally involve dileptons orjets plus missing ET signals. The signatures are expected to be spectacular, and detector performances are probably less crucial than elsewhere. All this is very, very, very speculative. But it's probably the most ground-breaking discovery LHC/SLHC can possibly make. M de Palma, WG SLHC

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