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LHCf status report

LHCf status report. Oscar Adriani Università degli Studi di Firenze INFN Sezione di Firenze. Experimental set-up. Protons. Charged particles. 140 m. 140 m. Neutral particles. γ. 8 cm. 6 cm. Beam pipe. n. γ. π 0. Detector I Tungsten Scintillator Scintillating fibers.

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LHCf status report

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  1. LHCf status report Oscar Adriani Università degli Studi di Firenze INFN Sezione di Firenze

  2. Experimental set-up Protons Charged particles 140 m 140 m Neutral particles γ 8 cm 6 cm Beam pipe n γ π0 Detector I Tungsten Scintillator Scintillating fibers Detector II Tungsten Scintillator Silicon mstrips INTERACTION POINT IP1 (ATLAS) Detectors installed in the TAN region, 140 m away from the Interaction Point 1 • Here the beam pipe splits in 2 separate tubes. • Charged particle are swept away by magnets • We cover up to y Oscar Adriani 23/09/10

  3. LHCf : Monte Carlo discrimination g 106/107 generated LHC interactions at 7+7 TeV 1 minute exposure@1029 cm-2s-1 luminosity n p0 Oscar Adriani 23/09/10

  4. LHCf Operations at 900 GeV • 06 Dec – 15 Dec 2009 • 27.7 hours for physics • ~5x105 collisions at IP1 • ~2,800 shower events in Arm1 • ~3,700 shower events in Arm2 • 02 May – 27 May 2010 • 15 hours for physics • ~5.5x106 collisions at IP1 (Statistics x 11 wrt 2009) • ~44,000 shower events in Arm1 • ~63,000 shower events in Arm2 • Beam Gas significantly reduced wrt 2009 Oscar Adriani 23/09/10

  5. 2009 vs 2010 2009 2010 Very big reduction in the Beam Gas / Bunch crossing ratio!!!! Very big increase of the ‘signals/noise’ ratio due to higher intensity Oscar Adriani 23/09/10

  6. Arm1 Spectra at 900 GeV Preliminary MC normalized to the total number of events in the 2 towers,without PID. Only one normalization factor common to all models Only statistical errors are quoted Oscar Adriani 23/09/10

  7. Arm2 Spectra at 900 GeV Preliminary Preliminary MC normalized to the total number of events in the 2 towers,without PID. Only one normalization factor common to all models Only statistical errors are quoted Oscar Adriani 23/09/10

  8. LHCf 2010 runs (mainly at 7 TeV) • Detector shows good performance with stable quality. • Energy scale calibration with the p0 peak!!!! • Good stability < ±1% level. • We started to have some radiation problems in the last periods. • Thanks a lot to all LHC people for providing us 100 mrad crossing angle!!! • Very important for physics to enlarge the PT acceptance • Detectors were removed on July 20, 2010 Oscar Adriani 23/09/10

  9. Acceptance gain due to Crossing Angle No crossing angle 100 mrad crossing angle Arm1 Arm1 A very significant gain in acceptance is clearly visible! Oscar Adriani 23/09/10

  10. Operation at 7 TeV Without crossing angle (30/03 – 05/06) With 100mrad crossing angle (25/06 – 20/07) Runs are taken in many different vertical position and with/without Xing angle Oscar Adriani 23/09/10

  11. 7 TeV collisions 1 TeV gamma-ray shower @ Arm2 Transition curve in towers X-view of silicon strip Y-view of silicon strip Oscar Adriani 23/09/10

  12. Arm2 event display p0 at 7 TeV Silicon layers 25 mm tower 32 mm tower Scintillator layers • Robust sample • Good energy calibrator Tower 32mm 25mm Oscar Adriani 23/09/10

  13. Beam position analysis: LHCf vs BPM Oscar Adriani 23/09/10

  14. Please note the Very High Energy! p0 mass and energy spectrum (Arm1) Preliminary Preliminary Preliminary DM/M=6.3MeV/135MeV=4.7% Oscar Adriani 23/09/10

  15. p0 mass and energy spectrum (Arm2) Preliminary DM/M=2.3% Preliminary Using only data taken before April 13th Oscar Adriani 23/09/10

  16. Particle ID: L90% Oscar Adriani 23/09/10

  17. PID study Energy spectra with not PID biased By fitting the L90% distribution with the superposition of 2 components (gamma-rays and hadrons), the efficiency and purity can be estimated from the data themselves. After the correction Before the correction Oscar Adriani 23/09/10

  18. Arm1 Gamma-ray like Hadron like preliminary preliminary Arm2 Gamma-ray like Hadron like preliminary preliminary Measured Spectra at 7TeV Very high statistics !! only 2% of all data Oscar Adriani 23/09/10

  19. Arm1/Arm2 Comparison • Same geometrical regions and same runs are selected • Correction for different livetimes Red : Arm1Blue : Arm2 Red : Arm1Blue : Arm2 Oscar Adriani 23/09/10

  20. h search All data taken with zero-crossing angle and low luminosity In the High Lumi/High Pile Up runs we don’t see h (combinatorial background) Oscar Adriani 23/09/10

  21. Luminosity with VdM scan with Front Counter Data Oscar Adriani 23/09/10 σx & σy are measured in VdM scan (May 9th) independently from interaction model or detector Calculate luminosity with this VdM scan Calculate “FC rate  Luminosity” Conversion Factor to be independent from MC

  22. VdM scan May 9th, 2010 Horizontal scan FC rate of arm1 / 1000 Beam position - start of scan +0.3mm Beam position - end of scan +0.3mm sx measured by FC + Lumi measured perfectly compatible with Atlas! Oscar Adriani 23/09/10

  23. 3% Radiation Damage Dose measured by the dosimeters behind the calorimeters p0 mass peak Oscar Adriani 23/09/10

  24. LHCf removal • LHCf has completed the basic physics program at 7 TeV  • LHCf has been removed on July 20th, during a short technical stop (a little bit ) • Laser calibrations were done for few weeks after the removal (Annealing) • Test beam is foreseen from October 15 to 28 • 3 days main users • 10 days parasitic run Oscar Adriani 23/09/10

  25. Future activities (I) 2011 • Replace plastic scintillators with Rad Hard GSO (prepared by Japan side) in Florence Clean Rooms • Produce 2 new silicon modules to replace partly defective ones + 2 spares • Modify the silicon layers positions to improve silicon-only energy resoution • Test beam at SPS to calibrate Arm1&Arm2 • Test beam at GSI to intercalibrate the Silicon Pace3 response with relativistic High Z Nuclei Oscar Adriani 23/09/10

  26. EJ260 R&D for the detector upgrade. Scintillating Fibers ⇒GSO bars Plastic scintillators (EJ260) ⇒ GSO scintillators Radiation damage measured by Ion beams MIP peak Oscar Adriani 23/09/10

  27. 8 Silicon Layers 6 6 12 12 18 26 34 42 X0 New silicon layers arrangement Oscar Adriani 23/09/10

  28. Future activities (II) • 2012 • Install the detectors at RHIC? • RHIC can accelerate: • p-p up to 250 GeV/nucleon • Ions up to 100 GeV/nucleon • They have already done deuteron-Gold • They could do p-Light ion • RHIC beam pipe arrangement • Situation similar to LHC • Single beam pipe split in 2 at 20 m from IP • Space available ~ 10 cm • LHCf can fit very well inside! • p0 can be reconstructed as we are doing in LHC! • Sqrt(s)min=4 mp d/hdet • d=20 m, hdet = 8 cm  Sqrt(s)min= 135 GeV • More news in 2011—> Stay tuned!!!!!!! Oscar Adriani 23/09/10

  29. Future activities (III) • 2013-2014 • Re-install Arm1&Arm2 at LHC when the energy will be raised to 13/14 TeV • Necessity to mantain the Cern infrastractures: • Control room • Electronics pool material • Safety infrastructures • Racks in underground areas • Team account • Etc. etc. etc. Oscar Adriani 23/09/10

  30. Conclusion • LHCf has completed the basic physics program at 7 TeV • LHCf was removed from TAN on July 20th, 2010 • Test beam is foreseen in October 2010 • The detector will be upgraded during 2011 to improve radiation hardness • GSO will replace plastic scintillator • More energy measurement oriented silicon arrangement • RHIC Option for 2012?  Stay Tuned!!!!!!!!!! • LHCf will certainly be back in the TAN for the 14 TeV run! Oscar Adriani 23/09/10

  31. Backup slides Oscar Adriani 23/09/10

  32. dE MC (DPMJET3) Measured layer Studies of detector responses LPM effect The radiation length for high energy particles seems to become longer in the heavy matter. - Confirmation of the LPM effect - Effect to the energy reconstruction and PID etc. Transition curve for 1.5TeV γ (MC) presented by SAKO Detector response for hadrons by beam test data at SPS done in 2007 Transition curve for 350GeV/c protons protons with 350GeV/c and 150GeV/c ⇔LHC: 450GeV+450GeV LHCf Detector Beam Pipe Presented by MASE Silicon Tracker Oscar Adriani 23/09/10

  33. Radiation Damage Studies Scintillating fibers and scintillators • Expected dose: 100 Gy/day at 1030 cm-2s-1 • Fewmonths @ 1030 cm-2s-1: 10 kGy • 50% light output • Continous monitor and calibrationwith Laser system!!! 30 kGy 1 kGy The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 Alessia Tricomi University & INFN Catania Oscar Adriani 23/09/10

  34. Particle Identification Longitudinal development of Hadron shower Longitudinal development of g shower Thin for hadronic interaction(1.7l) Thick for E.M.interaction (44X0) Definitionof L90% Gamma-rays: L90%<16 r.l. + 0.002 x SdE Oscar Adriani 23/09/10

  35. QGSJET2 QGSJET2 QGSJET2 QGSJET2 Data Data Data Data Results at 900GeV: PID Preliminary Gamma-rays: L90%<16 r.l. + 0.002 x SdE Oscar Adriani 23/09/10

  36. L90%<18X0 Constant e cut Oscar Adriani 23/09/10

  37. RHIC Physics Case • p-Light Ion • This measurement will allow to directly measuring the characteristic of the HECR-atmosphere interactions, without having to rely on the approximation usually done to go from the p-p collision to the p-nucleus collision (Glauber approximation). • p-p • We propose also to run the RHICf experiment in the p-p collisions, to have the possibility to directly check the validity of the Glauber approximation at 200 GeV center of mass energy by comparing the p-p with the p-LI results. Oscar Adriani 23/09/10

  38. Beam Position Analysis from the LHC data Positive; upward in V outward in H BPMSW IP θ Offset; b 140m Theoretical center BPMSW 43m Oscar Adriani 23/09/10 Beam position (b) and angle (θ) can be determined from the measurements of two BPMSW (beam position monitor) Expected position (neutral center) on the LHCf detector at 140m away can be calculated from these numbers Analysis done by Simon White

  39. Arm1 Arm2 Coincidence FC LHCf-CAL ZDC ZDC ZDC BRAN-Sci BRAN-IC Beam pipe Neutral particles TAN Gaussian fit FrontCounter as a good luminosity monitor Stay all the time • FC is working very well for luminosity monitoring (Very useful monitor for the machine) • Continuous monitoring w/ independent DAQ now available. See Page1 “LHCf experiment” • Conversion to “luminosity” from FC rate is now under study by MC Page1 LHCf page lumiscan Oscar Adriani 23/09/10

  40. ATLAS online (w/o calibration) VdM scanning Oscar Adriani 23/09/10

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