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Report on CMS Status Alan L. Stone on behalf of the CMS Collaboration

Report on CMS Status Alan L. Stone on behalf of the CMS Collaboration. Summary from CMS Week Update on Solenoid CRaFT1. CMS Global Runs. CRUZET4 & MWGR. Cruzet4. September 10. Cruzet3. Cruzet2.

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Report on CMS Status Alan L. Stone on behalf of the CMS Collaboration

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  1. Report on CMS StatusAlan L. Stoneon behalf of the CMS Collaboration Summary from CMS Week Update on Solenoid CRaFT1

  2. CMS Global Runs CRUZET4 & MWGR Cruzet4 September 10 Cruzet3 Cruzet2 • We had several global runs: CRUZET 3 & 4, regular midweek GRs, a first go at some data with magnetic field. • Started in first week of September with continuous 24/7 operation. • Beam monitoring online first week September. • Successful beginning at the September 10 LHC startup. • CMS shifts running continously since (40 hours of beams where CMS was always taking data w/o Tracker & Pixel). Cruzet1

  3. Notes From The First Beam • From September 8 we ran continuously 24/7 until LHC incident of Sep 19th. • Since beginning of September we routinely readout ALL of installed CMS detectors in global runs. • All triggers are now operational (some still being improved) • Stability of running with all CMS components proved (also at high trigger rate, ran for 1 Hour at > 50 KHz, ~ 1 shift at >20 Khz) • HLT operational commissioning progressing fast: we are now running with a version which could have been used for early running at LHC, although not fully ‘stressed‘ • Beam monitoring equipment ‘appeared’ just in time but worked reliably from day 1, and are now familiar background features of the control room. • Data flow: had to adapt to ‘unforeseen’ features of real data and did so VERY efficiently: we are sure that we have not yet seen all possible features, but we are confident that ‘solutions’ would be found rapidly.

  4. CSC “Halo Muon” Trigger  Single Beams ME+ ME x TOF  2 bx Normal proton collisions (Beam-1) halo muon • LHC mode: both endcaps trigger simultaneously on IP muons • “Halo Muon” trigger: CSC Track Finder selects tracks with small  • Trigger on outgoing endcap (i.e., ME for Beam-1) •  Approximate timing of muons from IP • [Note: for first beams, the incoming endcap was also included in the trigger (delayed by 2bx). This is no longer true…] http://cms-project-cmsinfo.web.cern.ch/cms-project-cmsinfo/news.html

  5. Beam Halo Event Through Both Endcaps • Single beam bunch in LHC (~2x109 protons) • Beam passes through CMS  beam dump into collimators about 150m away from CMS • Beam captured  several turns Run 62384 Event 56199 More event displays are stored athttp://www.nuhep.northwestern.edu/~schmittm/CMS/TEMP/event_displays/ • Synchronous “splashes” of muons + stuff • Synchronous muons approximately parallel to beam

  6. Ramping The Solenoid (1) • 3T test on 29-30 August (Fri/Sat) • Fringe field: • Balconies in UXC: much local variation, values up to 350 Gauss (local shielding for Tracker cooling pumps worked) • USC (S1&S2): ~50 Gauss at the wall falling to 20 G at far end of rack row • Some concern that elevator failure may be result of fringe field First Solenoid ramp since 2006 (MTCC) when detector was above ground Fast dump  55-deg temp rise & 3-day recovery

  7. Magnetic Tracks!

  8. Ramping The Solenoid (2) Sep 16 & 18 Sep 8 CMS magnet tests on Mon Sep 8th. Problems appeared just below 3T, with HF (Forward HCAL), associated detectors and shielding closed. Field-induced effects on elevator, access system, instrumentation near LHC triplets. Field-induced relative movements of the HF, collar shielding and CASTOR table, leading to risk of affecting beampipe support.

  9. Ramping The Solenoid (3) • Mitigation of fringe field effects by securing affected areas during beam-off access periods [See above examples]. • Additional position and field-measuring equipment added. • Two additional beam tests on Sept 16th (up to 1.7T) and Sept 18th (up to 2.8T) with hall probes & watchers. • Movement and distortion of CASTOR, risking contact with beampipe. • Likely due to radial magnetic forces on unbalanced half-cylinder. • Decision to remove CASTOR. HF- must stay off for now. • Parallel work to secure CASTOR table, cradle, collar shield & I-beams. • Beam pipe to atmospheric pressure (Neon). • Magnet tests resumed on Thur (Oct 9th).

  10. Solenoid at 3.8 Tesla! • Magnet test reached 3.8T on Friday Oct 10th at 15h • It was found that the HF was attracted 10-15 mm to the IP, but with no danger to the beam pipe. • CRAFT1 begins on Monday (Oct 13th) with two days of 0T pedestal runs. • The remaining two weeks will proceed with 3.8T cosmic runs • Aside for a VIP day on Oct 21st.

  11. October Schedule 3.8T. 3.8T, 300M events, All detectors, 24/7 0T pedestals

  12. Goals & Outlook • Test of operation in full 3.8 T field with all subsystems. • Work on Central DCS and DSS interfaces and functionality. • Storage manager stability . • RPC endcaps: late delivery of supplies and current drawn in one wheel. • Validation & commissioining of Jet Trigger. • Gain operational experience with Tracker and Pixel Front End Detectors. • They have accumulated fewer hours than the rest of the experiment. • There were off for beams. • Consolidate running at High rates (> 50 KHz) for day-long operation. • More automatic central control • Anticipation of an overall reduction of the total number of shifters for next year. Currently >20 per shift. • Coherent and consistent error reporting and error handling across subsystems. • Define, practice and document precisely our operations procedures. • Accumulate 300 Million triggers with cosmic tracks . Should allow us to find enough hard muons not too far off from the beam line in permit a good alignment and calibration of our detector. • CMS is now a working experiment.

  13. LHC Collisions Part II

  14. Backup Slides

  15. HF & Collar/CASTOR Shielding Closure +end -end

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