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

J. Incandela – DOE Site Visit – January 17, 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 2

J. Incandela – DOE Site Visit – January 17, 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. 3 * Past and present technical personnel presented in next talks.

J. Incandela – DOE Site Visit – January 17, Silicon Strip Tracker 5.4 m End Caps (TEC 1&2) 2,4 m Inner Barrel & Disks (TIB & TID) Pixels Outer Barrel (TOB) volume 24.4 m 3 running temperature – 20 0 C 4 >200 m 2 of Si detectors

J. Incandela – DOE Site Visit – January 17, US production responsibilities 5.4 m 2.4 m Outer Barrel (TOB) ~105 m 2 End Caps (TEC) 50% Modules for Rings 5 and 6 and hybrid processing for Rings 2,5,6

J. Incandela – DOE Site Visit – January 17, US in the tracker 6

J. Incandela – DOE Site Visit – January 17, 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 m 2 ) UCSB: 4200 modules (~80 m 2 ), ~60% of US production and 40% of total surface area of tracker Relative cost of production ~35% (large cost savings to US CMS) 7

J. Incandela – DOE Site Visit – January 17, 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 8 *As of summer ’07 for institutions other than UCSB Project Leader: J. Incandela (UCSB) Deputy: R. Demina (UR)

J. Incandela – DOE Site Visit – January 17, 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 ( ) 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 9

J. Incandela – DOE Site Visit – January 17, 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 10

J. Incandela – DOE Site Visit – January 17, Common Mode Noise (CMN) 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 APV 3 APV 4 11

J. Incandela – DOE Site Visit – January 17, Module Production 7115 modules : Only 27 were not installable 2644 of 4,145,912 bad channels 99.96% good UCSB  best in CMS 2644 of 4,145,912 bad channels 99.96% good UCSB  best in CMS ~1 year 12 Ultimately needed to compress 2.5 year production schedule into a little over 1 year

J. Incandela – DOE Site Visit – January 17, TOB Complete Nov The + end of the TOB in the Tracker Support Tube (TST) 13

J. Incandela – DOE Site Visit – January 17, Some of US Group at CERN 14

J. Incandela – DOE Site Visit – January 17, 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. 15

J. Incandela – DOE Site Visit – January 17, Cosmics 16

J. Incandela – DOE Site Visit – January 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.

J. Incandela – DOE Site Visit – January 17, Tracker Readied for Installation

J. Incandela – DOE Site Visit – January 17, Tracker Installation 19

J. Incandela – DOE Site Visit – January 17, 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 20

J. Incandela – DOE Site Visit – January 17, Su mm er Incandela, Mannelli CMS Tracker Upgrade Possible High Pt Discrimination Scheme Stacks of Sensor Pairs, improved local Pt measurement Straw-man Layout Example 12 Measurement Layers Organized in Super-Layers Each Super-Layer = Stack of 2 Sensor Pairs (4 measurement layers / Super-Layer) Inner Super-Layer ~ 20cm (?) Middle Super-Layer ~ 60cm Outer Super-Layer ~ 100cm 21

J. Incandela – DOE Site Visit – January 17, α 22 Tangent-Point Reconstruction

J. Incandela – DOE Site Visit – January 17, 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 23

J. Incandela – DOE Site Visit – January 17, 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 P T, 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) 24

J. Incandela – DOE Site Visit – January 17, 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

J. Incandela – DOE Site Visit – January 17, 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 e or  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) 26

J. Incandela – DOE Site Visit – January 17, Dilepton + E T + jets Njets ee  ee all Campagnari, Kalavase, Kovalskyi, Krutelyov, Ribnick 27

J. Incandela – DOE Site Visit – January 17, 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 28

More Information

J. Incandela – DOE Site Visit – January 17, 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 Noisy 1 sensor open 2 sensors open Pinholes Bad Channel Flags Noise Measurement 30

J. Incandela – DOE Site Visit – January 17, 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. 31

J. Incandela – DOE Site Visit – January 17, Hybrid Via Opens Opens in the power vias appeared with time Inconsistently plated Fix: add intermediate kapton layer Kapton Glue Kapton Glue 32

J. Incandela – DOE Site Visit – January 17, 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. 33

J. Incandela – DOE Site Visit – January 17, Begin Installing Rods March ‘06 Two teams of 5 technicians includes 2 US technicians 34

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J. Incandela – DOE Site Visit – January 17, APV  m 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

J. Incandela – DOE Site Visit – January 17, 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 – DOE Site Visit – January 17, J. Incandela, Jan. 17,2008 Blue = double sided Red = single sided Strip lengths 10 cm (innermost) to 20 cm (outermost) Strip pitches 80  m (innermost) to 205  m (outermost) 500  m thick high resistivity 320  thick low resistivity Silicon Strips 38

J. Incandela – DOE Site Visit – January 17, Misalignments and P T Resolution Single  sample, p T =100 GeV Only rms shifts greater than 10  m degrade pt resolution 39

J. Incandela – DOE Site Visit – January 17, Factoids 10,000,000 individual strips 78,000 APV readout chips 26,000,000 individual wirebond wires 207 m 2 of silicon 100 kg of Silicon 40