1 / 40

Joe Incandela University of California Santa Barbara DOE Site Visit Jan 17, 2008

UCSB in CMS. Joe Incandela University of California Santa Barbara DOE Site Visit Jan 17, 2008. Overview. The LHC is an unprecedented opportunity and challenge UCSB has been committed to the success of CMS for many years CMS has often turned to UCSB in times of critical need

tana
Download Presentation

Joe Incandela University of California Santa Barbara DOE Site Visit Jan 17, 2008

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. UCSB in CMS Joe Incandela University of California Santa Barbara DOE Site Visit Jan 17, 2008

  2. Overview • The LHC is an unprecedented opportunity and challenge • UCSB has been committed to the success of CMS for many years • CMS has often turned to UCSB in times of critical need • It was recognized very early on that UCSB would be key to the success of the CMS micro-strip tracker • One of the largest contributors to the CMS tracker by almost any metric. • Found problems and averted failure of the tracker and CMS multiple times • Provided key manpower for final assembly and testing of the tracker at CERN • Redesigned and installed critical-path services at point 5 • CMS has turned to UCSB to help prepare for first data • We continue to contribute to the tracker but have now expanded our role in CMS to include contributions to the physics program that often have collaboration-wide applicability and importance. • UCSB continues to be an important asset for CMS • Physics leadership and data analysis • Tracker Maintenance and Operation, upgrade R&D and construction

  3. Current research personnel on CMS* • Faculty • Majority if not all of our research time on CMS • Post-docs • Dmytro Kovalskyi - (Babar) • Vyacheslav (“Slava”) Krutelyov – (CDF) • Victor Pavlunin – (CLEO) • Roberto Rossin – (CDF) • Jean-Roch Vlimant – (DZero) • Steven Lowette – (CMS) • Tom Danielson – (Zeus) • Students • Mariarosaria D’Alfonso • Chris Justus • Puneeth Kalavase • Sue Ann Koay • Jim Lamb • Jake Ribnik • Finn Rebassoo • Wing To • Jess Reidel • All have and will continue to contribute to the tracker. * Past and present technical personnel presented in next talks.

  4. Silicon Strip Tracker >200 m2 of Si detectors Outer Barrel (TOB) Pixels End Caps (TEC 1&2) Inner Barrel & Disks (TIB & TID) 2,4 m 5.4 m volume 24.4 m3 running temperature – 20 0C

  5. US production responsibilities End Caps (TEC) 50% Modules for Rings 5 and 6 and hybrid processing for Rings 2,5,6 Outer Barrel (TOB) ~105 m2 2.4 m 5.4 m

  6. Sensors: Pitch adapter: Frames: Hybrid: Hybrids: factories Brussels Brussels CF carrier Strasbourg US in the tracker CERN Perugia Wien Pisa Louvain RU Sensor QAC Karlsruhe Strasbourg Module assembly UCSB FNAL Perugia Bari Lyon UCSB Brussels Wien FNAL Bonding & testing UCSB FNAL Aachen UCSB FNAL Wien Zurich Strasbourg Karlsruhe Padova Pisa Torino Bari Firenze Integration into mechanics ROD INTEGRATION TIB - TID INTEGRATION PETALS INTEGRATION Aachen Louvain Lyon Strasbourg Karlsruhe Pisa FNAL Brussels UCSB TOB assembly TIB - ID assembly TEC assembly TEC assembly Sub-assemblies At CERN Pisa Aachen Karlsruhe . -- > Lyon TK ASSEMBLY At CERN

  7. An All Silicon Tracker • CMS decision for an all silicon tracker in 2000 • Concerns about Micro Strip Gas Chambers (MSGC) • Cost for a silicon had fallen • US was on board • US in the tracker • 1997: First US workshop (FNAL) • 1998: An initial proposal • 900 modules • 2000: All of the Tracker Outer Barrel (TOB) • 5200 modules • Final: All TOB + Fraction of Tracker End Caps (TEC) • 7100 modules (~135 m2) • UCSB: 4200 modules (~80 m2), • ~60% of US production and 40% of total surface area of tracker • Relative cost of production ~35% (large cost savings to US CMS)

  8. US Tracker Group* • Brown University • L. Christofek, S. Esen, D. Giordano,G. Landsberg, M. Nahrain, H.D. Nguyen, T. Speers, K.V. Tsang • University of California, Riverside (UCR) • G. Hanson, H. Liu, G.Y. Jeng, G. Pasztor, A. Satpathy, R. Stringer • University of California, Santa Barbara (UCSB) • C. Campagnari, M. D’Alfonso, T. Danielson, J. Incandela, C. Justus, P. Kalavase, A. Kaminskiy, S. Koay, D. Kovalskyi, V. Krutelyov, S. Kyre, J. Lamb, S. Lowette, F. Rebasso, J. Ribnik, J. Richman, R. Rossin, D. Stuart, S. Swain, W. To, D. White, J-R Vlimant+ technicians • University of Illinois, Chicago (UIC) • E. Shabalina, C. Gerber, S. Khalatian, V. Bazterra • Fermilab (FNAL) • L. Bagby, P. Bhat, M. Demarteau, H. Jensen, M. Johnson, T. Miao, S. Moccia, C. Noeding, J. Spalding, L. Spiegel, Y. Sverev, S. Tkaczyk • University of Kansas (KU) • P. Baringer, A. Bean, J. Chen, T. Moulik • Massachusetts Institute of Technology (MIT) • S. Hahn, K. Hahn, P. Harris, M. Rudolph, P. Everaerts, K. Sung • University of Rochester (UR) • R.Demina, Y. Gotra, S. Korjenevski, D. Miner • Mexican Consortium: • Cinvestav: H. Castilla, R. Perez, A. Sanchez Puebla: E. Medel, H. Salazar • San Luis Potosi: A. Morelos Project Leader: J. Incandela (UCSB) Deputy: R. Demina (UR) *As of summer ’07 for institutions other than UCSB

  9. UCSB in the CMS Tracker • Module and rod production at UCSB • A substantial effort for many years - completed last year • At peak ~ 25 people including many outstanding undergraduates • Tracker Integration at CERN • We have had a presence at CERN on the tracker since 2005 • Rod reception, Tracker Assembly and testing (2005-2007) • UCSB technicians were involved in construction • UCSB was responsible for all testing of the Tracker Outer Barrel (TOB) • The UCSB testing team was the core of CERN-based expertise in detector operation and played a major role in operation and testing during the slice test and cosmics data-taking of the fully assembled tracker. • A UCSB physics B.S. spent one year on DAQ integration • Currently UCSB is contributing to preparations for first data • 1 Faculty, 2 post-docs, 3 students, 1 engineer and 1 tech. full-time at CERN • Other faculty, Post-docs, Students and Engineers make regular long visits to CERN to participate in point 5 activities

  10. Quality Assurance Found Serious Flaws • Common Mode Noise (CMN) in ST sensors (TOB,TEC) >12,000 sensors to Hamamatsu Corporation • Broken traces on hybrid pigtails: (TIB, TOB & TEC) • integrated the pigtail into the kapton layers. • Poorly plated vias: (TIB, TOB & TEC) • change hybrid production methodology and QA. • Degradation of Ag epoxy bias connection. (TOB & TEC) • bias connection made with wirebonds (as already done for TIB). • I2C communication failures on rods: (TOB & TEC) • Redesign interconnect cards (not used in TIB). • Sensor damage due to discharge: (TOB,TEC) • Resolved by encapsulating and modifying power supplies (TIB did not have this problem). • Methods drew upon CDF, D0, Babar, CLEO etc. • Avoided potentially catastrophic failure of tracker • Led to unprecedented quality and performance for physics

  11. UCSB found modules with SGS Thomson Microelectronics (STM) sensors showed CMN Micro-discharge More modules developed the problem over time even if only stored on shelf! We postulated some kind of chemical deterioration. After 1.5 years of intense effort, it was determined to be corrosion Common Mode Noise (CMN) APV 4 APV 3

  12. Module Production Ultimately needed to compress 2.5 year production schedule into a little over 1 year ~1 year 7115 modules : Only 27 were not installable • 2644 of 4,145,912bad channels • 99.96% good channels @ UCSB  best in CMS

  13. TOB Complete Nov. 2006 The + end of the TOB in the Tracker Support Tube (TST)

  14. Some of US Group at CERN

  15. TOB Noise Performance • Noise distribution after common mode noise subtraction is Gaussian over nearly 4 decades! • Only a few dozen outliers = known bad channels. • Edge strips responsible for the small shoulder (black) and are removed (blue). • Average noise per chip is rescaled to arbitrary value of 10 ADC to correct for gain variations.

  16. Cosmics

  17. Tracker Commissioning • Cosmic slice test data validation: (Rubinstein, Stuart) • Online zero suppression • optimal clustering thresholds • TOB alignment • Check momentum spectrum with scattering • Calibration monitoring • Commissioning: (Justus, Rubinstein, To, Stuart) • Cabling and electronics testing in UX5 • Calibration monitoring in Nov. global run • Calibration validation and monitoring will continue through connection and checkout.

  18. Tracker Readied for Installation

  19. Tracker Installation

  20. Upgrade R&D Issues • CMS silicon has limited lifetime. • SLHC will require a new tracker. UCSB involvement • Commercial, large-scale silicon pixel production (UCSB has been involved in discussions with HPK) • Cooling and material budget • One of the groups in CMS that spearheaded the idea of using fewer but more powerful sensing layers (long-pixels), • Studying ways of achieving low mass mechanics shared by more than one layer, thinned sensors and electronics • Thinking outside the box to achieve adequate cooling without vast increases in material • Simulations for physics performance • GEANT4 representations of pixel-superlayers • Ability to change geometry on the fly • Optimize design within a specific design class • Plan involvement in electronics, e.g. L1 track trigger R&D

  21. Incandela, Mannelli CMS Tracker UpgradePossible High Pt Discrimination SchemeStacks of Sensor Pairs, improved local Pt measurement Straw-man Layout Example 12 Measurement Layers Organized in Super-Layers EachSuper-Layer = Stack of 2 Sensor Pairs (4 measurement layers / Super-Layer) Inner Super-Layer ~ 20cm (?) Middle Super-Layer ~ 60cm Outer Super-Layer ~ 100cm 21

  22. Tangent-Point Reconstruction α 22

  23. UCSB in Physics I • Many contributions completed, underway, foreseen: • Development of tools for the collaboration • Tracking and triggering (Richman et al.) • Rapid, efficient and pure regional tracking in the High Level Trigger • Muons (Campagnari et al.) • Helping to develop robust muon reconstruction tools • Physics Analyzer Tool development (Lowette) • Facilitate data-access as well as access to new innovations • Will help those who are now saddled with detector installation and commissioning to ramp up quickly in physics analysis • On-shell effective theories (OSETs) (Koay, Rossin) • In collaboration with theorists, have developed a special tool to allow the rapid characterization of observations of non Standard Model (SM) phenomena in CMS data • Enables CMS to rapidly characterize any new signals that may be seen and quickly point the way to new directions of enquiry

  24. Offline Muon Reconstruction and Identification • Developed “propagator” to swim track and cov matrix into -system • B-field, dE/dX, multiple scattering essential to  reconstruction (V. Krutelyov) • Developed alternative inside-out  reconstruction algorithm • Increased efficiency at low PT, redundancy, robustness (D. Kovalskyi, C. Campagnari, J. Ribnick) • Development of muonID algorithms • (J. Ribnick, C. Campagnari, D. Kovalskyi, V. Krutelyov) • Coordination of muon isolation tools development (V. Krutelyov) • Definition of muon object content and format (D. Kovalskyi)

  25. Muons, Tracking, and the High Level Trigger Main goals: design, implementation, and testing of Level 3 Muon Trigger • No silicon tracking performed prior to L3. • Algorithm development, tools, studies of trigger rates Improvement in efficiency for matching muon to correct track in dense tracking environment. Richman, Jean-Roch Vlimant, Finn Rebassoo

  26. UCSB in Physics II • Data-driven methods for normalizing SM backgrounds and new physics with specific topologies • (Pavlunin, Stuart…) Normalize SM Z+jets in forward region • ( D’Alfonso, Incandela…) Use W+jets with W decaying to en or mn to normalize Z+jets with Z decaying to neutrinos • Study top dileptons (Campagnari et al) top lepton+jets (Lamb, Incandela) in preparation for new physics with leptons/jets/missing energy • Full feasilbility studies (CMS Physics TDR) • (Hill, Koay, Incandela) Studied Htt and showed that for the case of H decaying to bb, this channel may not be accessible at the LHC • Leadership roles in CMS Physics organization • Physics Coordination (JI, deputy phys coordinator) • Physics analysis (Claudio Campagnari, co-leader of top group)

  27. ee  Njets Njets e all Njets Njets Dilepton + ET + jets Campagnari, Kalavase, Kovalskyi, Krutelyov, Ribnick

  28. Conclusions • UCSB has been an important asset for CMS for many years • Large part of the success of the tracker project • We are now turning to the critical needs of the next phases • Commissioning, maintenance and operation of the tracker • Providing important tools for physics • Preparing to analyze data • R&D for the tracker upgrades • UCSB remains an important asset for CMS • A strong UCSB group is an important CMS–wide resource

  29. More Information

  30. Noise Measurement Noisy 1 sensor open 2 sensors open Pinholes Bad Channel Flags Clear, robust fault signatures • At UCSB we developed fixtures for • Minimum noise • Maximum sensitivity • And automated Fault-Finding: • Use results of many partially correlated tests to determine the type and location of faults • >99.9% faults are found with <0.01% error rate

  31. Adapting to Delays • The start of production was delayed >2 y • Production capacity had to be expanded • US CMS portion of project was increased 40% • Ultimately needed to compress 2.5 year production schedule into a little over 1 year • Required an enormous amount of organization, workflow analysis, failure modes analysis, etc. There was less than 3 days downtime due to equipment failure.

  32. Opens in the power vias appeared with time Inconsistently plated Hybrid Via Opens Kapton Glue Kapton • Fix: add intermediate kapton layer Glue

  33. Module Testing: Example of a Work Flow Plan Analyze movement of people in clean room, layout work areas to optimize efficiency, minimize interference and minimize errors.

  34. Begin Installing Rods March ‘06 Two teams of 5 technicians includes 2 US technicians

  35. APV25 • 0.25 mm IBM CMOS • 128 Channels • 50 ns CR-RC shaper • Clever sampling of charge in three intervals separated by 25 ns intervals Total charge on strip in a single 25 ns bunch crossing obtained by de-convolution of signal from impulse response of amplifier Low noise and power • 192 cell analog pipeline • Diff. analog data output Expect < 3000 e noise for all detector types during CMS lifetime Radiation Hard- Performance unchanged after 50 MRad

  36. Tracker Readout System • Data for all channels are readout to the Front End Driver (FED) which then applies • Zero suppression • Pedestals • Common mode filtering • Clustering • Readout is analog optical

  37. J. Incandela, Jan. 17,2008 Silicon Strips 500 mm thick high resistivity Blue = double sided 320 mm thick low resistivity Red = single sided Strip lengths 10 cm (innermost) to 20 cm (outermost) Strip pitches 80mm (innermost) to 205mm (outermost)

  38. Misalignments and PT Resolution Single m sample, pT=100 GeV Only rms shifts greater than 10 mm degrade pt resolution

  39. Factoids 10,000,000 individual strips 78,000 APV readout chips 26,000,000 individual wirebond wires 207 m2 of silicon 100 kg of Silicon

More Related