1 / 26

Task C Activities in the CMS Experiment

Task C Activities in the CMS Experiment. Greg Landsberg DOE Site Visit September 28, 2006. Brown and CMS. Next energy frontier and a natural way for our group to evolve is LHC

agalia
Télécharger la présentation

Task C Activities in the CMS Experiment

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. Task C Activities in the CMS Experiment Greg Landsberg DOE Site Visit September 28, 2006

  2. Brown and CMS • Next energy frontier and a natural way for our group to evolve is LHC • While have realized this a while ago, it would have been a hard decision to move part of our DOE-supported group away from DØ w/o stretching thin our major responsibilities there • The NSF CAREER Award won by GL in June 2003 allowed us to expand in the new direction w/o compromising our DØ strength • Why CMS? • Better detector • Strong Fermilab presence allowing for an adiabatic transition • December 2003: formal application to join CMS • March 2004: presentation of our application at the CMS Week • June 2004: Brown was voted in and became a full member of CMS • At the same time, Ryan Hooper, a new RA to work on DØ and CMS has been hired using the NSF Grant • Based on our strong ties with Fermilab’s SiDet, we have joined Tracker Outer Barrel construction project • Where do we stand now, two years since we’ve joined? Greg Landsberg, Task C Activities in CMS

  3. CMS – Soon to be Lowered! September 2006 CMS Week Greg Landsberg, Task C Activities in CMS

  4. CMS Explained [Jos Engelen, SLAC 2006 Summer School] Greg Landsberg, Task C Activities in CMS

  5. CMS All-Silicon Tracker Brown group involvement 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 Greg Landsberg, Task C Activities in CMS

  6. TOB Construction Major hardware project accomplished via joint effort of Brown, Fermilab, KU, Rochester, UCSB, UIC, and UCR Two mirror production facilities: Fermilab and UCSB Some TOB statistics: Total number of modules: 5208 + 5% spares Total number of rods: 688 + 5% spares Total silicon area: ~1000 ft2 Total silicon weight: ~100 lbs Brown involvement: Q&A, rod assembly, single-rod test stand People: GL, Ryan Hooper, Hai Duong Nguyen, Patrick Tsang, Scott Wolin, several more SS Rod production took place in FY2006 (November-July) Uncovered and fixed many problems since mid 2005: Common mode noise in ST sensors – replaced w/ Hamamatsu Wire bond breakage due to vibration – module encapsulation I2C communication problems – redesigned cards Degradation of the Ag-based epoxy bias connection – switched towire-bonding; Sensor damage due to discharges between the ground and the silicon surface – encapsulated wire bonds and modified HV power supplies Despite the unexpected delays, the project has been successfully finished All the rods have been assembled, tested, and delivered to CERN on time! Greg Landsberg, Task C Activities in CMS

  7. Rods & Single-Rod Test Stand Single-Rod Test Stand (SRT),and the “Brown Box” for reading rod temperature.Over 700 rods went through SRT An assembled rod and its readout end Greg Landsberg, Task C Activities in CMS

  8. Typical SRT Rod Failure SRT Opto Scan and Noise Saturated AOH laser channel Greg Landsberg, Task C Activities in CMS

  9. TOB at CERN – Rods Being Installed Greg Landsberg, Task C Activities in CMS

  10. Actual Rod Installation 100 mm axial precisionover the length of therod (~3ft)! [0.5 mil/sensor!] Greg Landsberg, Task C Activities in CMS

  11. LPC Activities LHC Physics Center (LPC) at Fermilab has been founded in 2004 as a “Mortar and Brick” foundation to accommodate critical mass of experts and support LHC physics efforts by the US community Brown group was one of the first groups to join (GL served on the Advisory Board in 2004-2005; Yuri Gershtein, than a Brown RA, became a convener of the e/g group) Many successes, from thorough work on development and optimization of ID algorithms within the new CMS software framework, to support of MC physics studies by students and software tutorials Helped our group to move to CMS adiabatically, without compromising the DØ connection LPC grew significantly over the last two years; still remains to be seen if the critical mass of experts can be achieved during CMS running Could serve as a good alternative to maintaining the core of the group at CERN (COLA, remoteness, need to relocate several people at once) 2007 LHC pilot run will serve as a proof of principle In 2005-2006 GL took a year-long sabbatical supported by LPC and has been appointed as the LPC Trigger Group convener Meenakshi Narain just started as an LPC b-tagging Group convener Maintain LPC office space to provide students, postdocs, and commuting faculty with excellent working conditions Greg Landsberg, Task C Activities in CMS

  12. Triggering at Hadron Colliders LHC: stot = 107.3 ± 1.2 mb [Block, Halzen, hep-ph/0510238 ] • e+e- colliders: low total cross section, low rates • Trigger pretty much on everything, perhaps with the exception of very forward processes (low-angle Bhabha) • Hadron colliders: enormous cross section, unattainable rates • Trigger is very selective • Only small fraction of collisions is written to tape • Additional complications due to pile-up • LHC: • stot = 110 mb, sin ~ 70 mb • L = 1034 cm-2s-1 = 10 nb-1s-1 • 25 ns bunch crossing • Total rate: ~109 s-1 or ~20/crossing • An order of magnitude more complex triggering than that at the Tevatron [PDG] Greg Landsberg, Task C Activities in CMS

  13. Trigger Architecture Detectors Detectors Lvl-1 Front end pipelines Lvl-1 Front end pipelines Readout buffers Readout buffers Lvl-2 Switching network Switching network Lvl-3 HLT Processor farms Processor farms CMS: 2 physical levels “Traditional”: 3 physical levels • Must reduce 2.5-40 MHz of input interactions to 50-100 Hz • Do it in steps/successive approximations: “Trigger Levels” x400 rejection x1000 rejection Greg Landsberg, Task C Activities in CMS

  14. CMSLevel-1 Trigger Scheme Muons Electrons, Photons, Jets, MET 3<||<5 ||<3 ||<3 ||<2.1 0.9<||<2.4 ||<1.2 Greg Landsberg, Task C Activities in CMS

  15. LPC Trigger Group • Charge – in concert with the international CMS Online Selection PRS group • Simulate, develop, and maintain L1 and High-Level Trigger algorithms • Work on creating realistic trigger table for the startup pilot run, as well as for low and high luminosity physics running • Maintain and operate Remote Operations Center (ROC) at Fermilab – a mirror control room for the experiment • Participate in the MTCC (Magnet Test & Cosmic Challenge) shifts and data monitoring and analysis • LPC Trigger Group Statistics: • About 25 active members • Regular biweekly meetings (one later this afternoon!) • Two successful workshops (L1 & HLT) in the past year • Deep connection with Online Selection PRS group Greg Landsberg, Task C Activities in CMS

  16. LPC Trigger Group Activities • Contribution to vol.2 of the CMS Physics TDR (Brown, Fermilab, Wisconsin) • Trigger tables and rates (Brown, Fermilab, Wisconsin) • Optimization of the L1 Calorimeter trigger (Brown) • L1 calorimeter calibration and jet energy corrections (Brown, Wisconsin) • Implementation of the L1 calorimeter emulator in the CMSSW framework (TAMU, Wisconsin) • HLT Jet/MET trigger suite implementation and timing studies (Brown, UIC) • Remote Operations and Control (Fermilab, Maryland; Brown is getting involved) • Test beam and cosmics data analysis (Fermilab, UIC) • Calorimeter noise studies (Brown, Rochester, UIC) • Minbias trigger design (UIC) Greg Landsberg, Task C Activities in CMS

  17. L1 Calorimeter Trigger Optimization • Pursued by GL and Sara Vanini • Focus on the basics: • Systematic studies of noise • Adjusting trigger thresholds to match noise • Optimizing trigger algorithms • Improving turn-on and resolution • Improving MET resolution • In the process uncovered and fixed many trigger simulation bugs and cleaned up ORCA code and propagate fixes into CMSSW • Example: • greatly improved single jet trigger turn-on – an important tool for multiobject triggers (e+jets, m+jets, etc.) Original defaultthresholds ETgen, GeV Optimized thresholds ETgen, GeV Greg Landsberg, Task C Activities in CMS

  18. Hardware Implementation Proposed optimized thresholds have been endorsed and approved by the CMS HCAL Electronics and Trigger groups They are currently being implemented in firmware and the new L1 emulator code Brown group spearheads this effort and will redo simulations with the new software Also work on implementing and simulating dynamic baseline subtraction scheme Energy is determined as a weighted sum: E = fiEi over several time-slices Automatic baseline subtraction: fi = 0 Being implemented for HCAL: fi = -1.0, -1.0, 1.0, 1.0 Will require slight timing realignment (~1 ns) Robust against coherent noise and hot cells TB04 5% 70% 23% 2% Greg Landsberg, Task C Activities in CMS

  19. L1 Calorimeter Trigger Calibration Problem: CMS calorimeter is Non-linear Non-compensated Has h-dependent response Goal: correct for these deficiency via proper calibration either at the jet or the trigger tower level New L1 JES corrections: Fit (or take the mean) of ETgen – ETL1 distributions in bins of ET, h Effect on MET in W+jets: Left: ME|| resolution Right: ME|| pull Corrections remove pull , but worsen the resolution by similar amount  Next step: introduce “new dimension” in tower calibration: e/h After JES corr. No JES corr. [GL, Scott Wolin] [GL, Sara Vanini] Greg Landsberg, Task C Activities in CMS

  20. Future Plans CMS Hardware & Commissioning Our current CMS hardware project has been a success, but it came to an end Important to maintain hardware experience in the group, especially given new students and postdocs joining the group Want to maintain close ties with the US “Silicon Consortium” – work well together, common goal in bringing tracker online Will participate in TOB commissioning via ROC in MTCC-II (later this year) and underground SX5 cosmic running (2007) Consider manning test beam and commissioning shifts at CERN via short-term visits SLHC Upgrade A lot of opportunities for new major hardware efforts Participate in the SLHC Steering Group meetings and SLHC workshops CMS SLHC LoI will go to the funding agencies later this year [Hope for enthusiastic support from you guys!] Discussed participation in the following areas: Construction of a part of the CMS silicon tracker replacement L1 tracking trigger design and construction (hardware + firmware) More in Meenakshi’s presentation Greg Landsberg, Task C Activities in CMS

  21. The LHC Schedule [Winter 2006] Our contract renewal date: ~ 5fb-1, first physics papers! 2009 2010 2008 2011 2007 • Physics running: 140 days/year • ATLAS/CMS running: ~100 days/year • Typical efficiency for physics: 40% • Effective ATLAS/CMS running time/year: ~1000 hours ~ 4 x 106 s ~ 4 x 1038 cm-2 = 4 x 1014 b-1 = 400 pb-1 @ 1032cm-2s-1 • Note that the schedule below [R. Bailey, Aspen 2006] is “all goes well” scenario 2010, 25ns L~1x1034 cm-2s-1Ldt ~ 40fb-1 Pilot run, 75ns L~5x1030 cm-2s-1Ldt ~ 20pb-1 2009, 25ns L~1x1033 cm-2s-1Ldt ~ 4fb-1 2008, 75/25ns L~3x1032 cm-2s-1Ldt ~ 1.2fb-1 Greg Landsberg, Task C Activities in CMS

  22. Revised LHC Schedule (Summer 2006] • Pilot 2007 Run • Starts ~2 months later than previously expected • Accelerator runs at injection energy (450 x 450 GeV pp) • Expected luminosity: ~1029 cm-2s-1 • Collision data sometimes in November 2007: ~50 nb-1 • Three-month shutdown following with 14 TeV data in Spring 2008 • The goal to deliver a few fb-1 by the end of the run • The rest of the schedule stays the same Greg Landsberg, Task C Activities in CMS

  23. CMS Physics All what we have been doing is really driven by our desire to become major players in the CMS physics, in the same way we maintained physics leadership within DØ over the last 15 years Currently focus on low-level task: optimization, validation, and certification of trigger, reconstruction and particle ID See Tulika’s talk on this Actively contributed to the Volume 2 of the CMS Physics TDR Getting involved in the Pilot 2007 Run data analysis as a preparation to the 2008 physics run Picking/negotiating physics topics to work on – from rediscovering SM with the first data to searches for black holes at the LHC Use our two-decade experience and leading role in the Tevatron physics as a guiding star Greg Landsberg, Task C Activities in CMS

  24. (Wo)manpower on CMS – Doubling! FY2006 Greg Landsberg – PI (90%) Tulika Bose – RA (50%) Ryan Hooper – RA, NSF (75%) Sara Vanini – VRA (75%) Zongru Wan – VRA (20%) Hai Duong Nguyen – GS, M&O (100%) Patrick Tsang – SS (25%) Scott Wolin – SS, UTRA (20%) Total: ~4 FTE FY2007 Dave Cutts – PI (50%) Greg Landsberg – PI (80%) Meenakshi Narain – PI (50%) Tulika Bose – RA (75%) Leonard Christofek – RA (50%) Selda Esen – RA, NSF (100%) Aram Avetisyan – GS (75%) Paul Huwe – GS (40%) Hai Duong Nguyen – GS (100%) Patrick Tsang – GS (100%) 2-3 SS (50-75%) Total: ~8 FTE FY2005 • Greg Landsberg – PI (30%) • Ryan Hooper – RA, NSF (100%) • Hai Duong Nguyen – SS, M&O (25%) • 3 Temps –SS (75%) • Total: ~2 FTE Greg Landsberg, Task C Activities in CMS

  25. Our Newest Addition to the Group • Selda Esen, who is graduating from Turkish University of Cukurova this week and will start with us on October 1 • CMS thesis based on jet studies and HCAL test-beam data analysis • Will work 100% on CMS and replace Ryan Hooper • Supported by the NSF grant Greg Landsberg, Task C Activities in CMS

  26. Conclusions • Our 2004 bid for LHC, made possible by the NSF support, has paid up • Our group is now well-plugged and recognized within the CMS community and has contributed to several aspects of hardware, firmware, and software • Our adiabatic transition from DØ to CMS has been successful: we still maintain important responsibilities in DØ (Luminosity Monitoring, Level 3/DAQ, B-physics, Top, Single Top, New Physics Searches), while ramping up our CMS effort • Our CMS involvement doubled every year since we have joined CMS – while such a growth can’t be sustained much longer, it’s up to you to ensure that it will continue • LHC is imminent; three years from now we very well may be reporting a major discovery made possible by the Brown group efforts! Greg Landsberg, Task C Activities in CMS

More Related