1 / 44

LHCf Status Report

This status report provides a short review of physics topics and detector design for the LHCf experiment, including the current status of the detectors and their installation. It focuses on the measurement of photons and neutral pions in the very forward region of the Large Hadron Collider (LHC).

emolinar
Télécharger la présentation

LHCf Status Report

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. LHCf Status Report • Short review of physics topics and detector design • Status of the detectors • Status of the installation • Running scenario Measurement of Photons and Neutral Pions in the Very Forward Region of LHC Oscar Adriani INFN Sezione di Firenze - Dipartimento di Fisica dell’Università degli Studi di Firenze

  2. The LHCf Collaboration CERN D.Macina, A.L. Perrot USA LBNL Berkeley: W. Turner FRANCE Ecole Politechnique Paris: M. Haguenauer SPAIN IFIC Valencia: A.Fauss, J.Velasco JAPAN: STE Laboratory Nagoya University: Y.Itow, T.Mase, K.Masuda, Y. Matsubara,H.Matsumoto,H.Menjo, Y.Muraki,T.Sako,H. Watanabe Shibaura University Saitama: K.Kasahara Kanagawa University Yokohama: T.Tamura, K.Tanaka Waseda University: Y.Shimizu, S.Torii ITALY Firenze University and INFN: O.Adriani,, L.Bonechi, M.Bongi, G.Castellini, R.D’Alessandro, P.Papini Catania University and INFN: A.Tricomi LHCf Status Report

  3. Main problems in High Energy Cosmic Rays (E>1015 eV) Xmax(g/cm2) Energy (eV) • Composition • Spectrum / GZK Cutoff LHCf Status Report

  4. Development of atmospheric showers Simulation of an atmospheric shower due to a 1019 eV proton. • The dominant contribution to the energy flux is in the very forward region (  0) • In this forward region the highest energy available measurements of p0 cross section were done by UA7 (E=1014 eV, y = 5÷7) The direct measurement of the p production cross section as function of pT is essential to correctly estimate the energy of the primary cosmic rays (LHC: 1017 eV) LHCf Status Report

  5. Letter Of Intent: May 2004 Technical report: September 2005 Technical Design Report: February 2006 LHCC approval: June 7th, 2006 LHCf Status Report

  6. LHCf location in the IP1 of LHC Detectors should measure energy and position of g from p0 decays e.m. calorimeters with position sensitive layers Detector I Tungsten Scintillator Scintillating fibers Detector II Tungsten Scintillator Silicon mstrips INTERACTION POINT IP1 (ATLAS) ~140 m ~140 m Beam line • Two independent detectors on both sides of IP1 • Redundancy • Background rejection LHCf Status Report

  7. Installation of the detectors in the TAN absorbers at 140m from IP1 LHCf 96 mm LHCf Status Report

  8. Detector #1 Impact point (h) 2 towers ~24 cm long stacked vertically with 5 mm gap Lower:2 cm x 2 cm area Upper: 4 cm x 4 cm area 4 pairs of scintillating fiber layers for tracking purpose (6, 10, 30, 42 r.l.) Absorber 22 tungsten layers 7mm thick  44 X0(1.6 lI)in total (W: X0 = 3.5mm, RM = 9mm) q < 300 mrad 16 scintillator layers (3 mm thick) Trigger and energy profile measurements Energy LHCf Status Report

  9. Detector # 2 We use LHC style electronics and readout 2 towers 24 cm long stacked on their edges and offset from one another Lower:2.5 cm x 2.5 cm Upper: 3.2 cm x 3.2 cm 4 pairs of silicon microstrip layers (6, 12, 30, 42 r.l.) for tracking purpose (X and Y)  impact point q < 400 mrad 16 scintillator layers (3 mm thick) Trigger and energy profile measurements Absorber 22 tungsten layers 7mm thick  44 X0 (1.6 lI) in total (W: X0 = 3.5mm, RM = 9mm) Energy LHCf Status Report

  10. Performances of the LHCf Detector LHCf can measure (and provide to LHC) the center of neutral flux from the collisions Energy Resolution SciFi Position Resolution Measured at the SPS Beam Test in 2004 If the center of the neutral flux hits LHCf  << 1 mm resolution LHCf Status Report

  11. p0 mass resolution 2gidentified in the 2 towers Arm #1 DE/E=5% 200 mm spatial resolution Dm/m = 5% LHCf Status Report

  12. Monte Carlo g ray energy spectrum (5% Energy resolution is taken into account) 106 generated LHC interactions  1 minute exposure @1029 cm-2s-1 luminosity Discrimination between various models is feasible Quantitative discrimination with the help of a properly defined c2 discriminating variable based on the spectrum shape (see TDR for details) LHCf Status Report

  13. Model dependence of neutron energy distribution Original n energy 30% energy resolution LHCf Status Report

  14. Summary 1 • LHCf can do the proposed physics measurements • We will be able to measure π0 mass with 5% resolution. • We will be able to distinguish the models by measurements of π0 and γ • We will be able to distinguish the models by measurements of n • LHCf can provide on-line useful information to machine people (Relative luminosity, beam position, beam-gas rate etc.) LHCf Status Report

  15. Where are we with the detectors?

  16. Where we are with Arm1? Arm1 was fully assembled in Japan in July 2006 (scintillators + fibers + Tungsten) and fully tested at CERN in August 2006 beam test LHCf Status Report

  17. Where we are with Arm2? • Arm2 was partially assembled in Florence in July 2006 and brought to CERN for the Beam Test of August 2006 • Arm2 was fully assembled in Florence in April 2007 LHCf Status Report

  18. LHCf Status Report

  19. Front Counter (Both for Arm1&2) read by a MAPMT R7600U-00-M4 LHCf Status Report

  20. SPS Beam Test LHCf Detector Silicon Tracker Moving Table • Test was successful • Analysis is under way for • Energy calibration of the calorimeters • Spatial resolution of the tracking systems • CERN : SPS T2 H4 • 2006 Aug. 28 – Sep. 4 • Incident Particles • Proton 150,350 GeV/c • Electron 100,200 GeV/c • Muon 150 GeV/c Setup Trigger Scintillator LHCf Status Report

  21. An electron event as seen by Arm1 2 r.l. step 4 r.l. step 40mm Calorimeter : 196 GeV electron Transition Curve Scifi e- 196GeV LHCf Status Report

  22. Energy Calibration 10mm 6mm Problem: Determination of the conversion factor from ADC to Energy in each calorimeter layer ⇒Ai[ADC counts/MeV] (i: Layer） How to do? Compare data with simulation (EPICS), tuning with beam test data Event Selection (Centered events) Incident point 20mm 3mm from calorimeter center 40mm 5mm from calorimeter center Beam Profile 40mm Calorimeter 196 GeV e- RUN LHCf Status Report

  23. Data vs. Simulation 40mm Calorimeter : 196 GeVRed : Simulation Black : Experiment Ai = Mean(data) / Mean(simulation) Layer χ2D.O.F. 3 42.6 / 60 4 23.8 / 48 5 50.0 / 36 6 64.5 / 38 Simulations and data agrees well!!! Energy scale can be well inferred Work in progress to check the energy scale for different energies LHCf Status Report

  24. Few plots of the beam test results for silicon A high energy electron shower seen on x and y silicon X Y <Noise> ~ 5 ADC counts LHCf Status Report

  25. Y Energy measured 100 GeV electrons High Gain X LHCf Status Report

  26. Summary 2 • Both Arm1 and Arm2 have been completed • They have been exposed to Beam Test in 2006 • They are ready to be installed in the LHC LHCf Status Report

  27. Now the real installation in LHC… The idea is that installation takes place in 2 steps: Pre-installation Final installation In between the 2 installation the baking out of the beam pipe will be done (200 oC), so the detectors should be removed Pre-Installation dates have been fixed in Fall 2006 • LSS1L (Arm1) • 8/01/2007 to 26/01/2007  FINISHED! • LSS1R (Arm2) • 23/04/2007 to 11/05/2007  will FINISH today The dates for the final installation are still under discussion LHCf Status Report

  28. Before pre-installation a long preparatory job has been necessary: • Modifications of the TAN • Transport machine / Fork lift • Cables and fibers from USA15 to tunnel • Most of the control electronics and all the power supply system are located in the USA15 Atlas control room • > 200 m distance!!! • All the necessary cables have been pulled (~100 cables!!!) • All the connectors have been mounted • All the optical fibers have been installed • Electronic racks in USA15 LHCf Status Report

  29. Arm1 pre-installation • Thanks to all people involved in the installation!!!!! • TS/LEA • Transport team • Cables team • Atlas • Safety • Etc. etc. etc. From 8/01/2007 to 26/01/2007 No major problems came out Cables  OK Transport and installation  OK Laser calibration  OK Power supply from USA15  OK Manipulator and movements  OK Arm1 was dismounted at the end LHCf Status Report

  30. Transport and insertion in the TAN LHCf Status Report

  31. LHCf Arm 1 – Installation completed within15 minutes! LHCf Status Report

  32. Arm2 pre-installation From 23/04/2007 to 11/05/2007 No major problems came out Quartz fiber for calibration is damaged  should be replaced Cables  OK Transport and installation  OK Laser calibration  OK locally  TBD from remote Power supply from USA15  OK Manipulator and movements  OK No interference with BRAN Arm2 will be dismounted this afternoon LHCf Status Report

  33. LHCf Status Report

  34. Summary 3 • A huge work has been done to organize the installation • Pre-installation of Arm1 & Arm 2 were succesfull • Installation and removal is a ‘fast’ operation! (remote handling is under study) • Final installation dates are under discussion LHCf Status Report

  35. The LHCf operation in LHC

  36. Optimal LHCf run conditions Beam parameters used for commissioning are good for LHCf!!! No radiation problem for 10kGy by a “year” operation with this luminosity LHCf Status Report

  37. Optimal conditions for LHCf running! From R. Bailey presentation at January 2007 TAN workshop Stage 1 LHCf Status Report

  38. From R. Bailey presentation at January 2007 TAN workshop LHCf Status Report

  39. LHCf proposed running scenario • Phase-I • Run since the very beginning of LHC operations (Stage 1, 43 bunches) • Remove the detector for radiation issues when the machine goes to the Stage II (luminosity reaches 1031cm-2s-1) and reinstall the 3 Cu bars • Phase-II • Re-install the detector at the next opportunity of low luminosity run after removal of Cu bars (Totem dedicated runs? Possible LHCf dedicated runs?) • Phase-III • Future extension for p-A, A-A run with upgraded detectors? We are continously in touch with Machine and ATLAS peoples to agree on detailed running scenario LHCf Status Report

  40. LHCf: conclusions and plans • LHCf approved in June 2006 by the LHCC • Physics performances: • able to measure π0 mass with 5% resolution. • able to distinguish the models by measurements of π0 and γ • able to distinguish the models by measurements of n • Detectors: • Arm1 & Arm2 are fully ready • Test beam was done in 2006 to measure the performances • Installation phase well advanced • ARM1 already successfully pre-installed in January 07, • ARM2 already successfully pre-installed in April-May 07 • Final installation date is under discussion • Running conditions: • Three foreseen phases • Phase I: Run at the beginning of LHC operations (43 bunches) • Phase II: operation during low luminosity TOTEM runs or dedicated runs • Phase III: Heavy Ion runs ? Waiting for LHC beams!!! LHCf Status Report

  41. Back up Slides

  42. Evaluation of Ai 3% (Ai,99.7GeV) / (Ai,196GeV) Compare Ai with 196 GeV electron run to Ai with 99.6 GeV electron run. 99.6 GeV/c electron run ⇒ Ai,99.6GeV 196 GeV/c electron run ⇒ Ai,196GeV Ai,99.7 is 3% less than Ai,196in both calorimeter Very Preliminary!!!! LHCf Status Report

  43. Epics v.s. Geant4 W: 7mm Scintillator: 3mm x 16 100mm e- 100mm LHCf Status Report

  44. Y Beam profile 200 GeV electrons X LHCf Status Report

More Related