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Status report of the LHCf experiment: preparation for data taking

95° LHCC Meeting – September 24, 2008. Status report of the LHCf experiment: preparation for data taking. Oscar Adriani INFN Sezione di Firenze Dipartimento di Fisica dell’Università degli Studi di Firenze. LHCf Physics Topics – Short summary!. Experimental measurement:

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Status report of the LHCf experiment: preparation for data taking

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  1. 95° LHCC Meeting – September 24, 2008 Status reportof the LHCf experiment:preparation for data taking Oscar Adriani INFN Sezione di Firenze Dipartimento di Fisica dell’Università degli Studi di Firenze

  2. LHCf Physics Topics – Short summary! • Experimental measurement: • Precise measurement of g and p0 spectra in the very forward region at LHC • 7 TeV + 7 TeV in the c.m. frame  1017 eV in the laboratory frame: • We can better simulate in the biggest’s world laboratory what happens in nature when a Very High Energy Cosmic Ray interacts in the atmosphere • Why in the very forward region? • Because the dominant contribution to the energy flux in the atmospheric shower development is carried on by the very forward produced particles LHCC O. Adriani

  3. A ‘practical’ approach From the practical point of view LHCf’s measurements will be used to calibrate the Monte Carlo codes heavily used in the Cosmic Ray analysis • VHECR energy spectra • HECR Composition AGASA x 0.9 HiRes x1.2 Yakutsk x 0.75 Auger x1.2 (not enough) Berezinsky 2007 LHCC O. Adriani

  4. Detectors should measure energy and position of g from p0 decays e.m. calorimeters with position sensitive layers LHCf: location and detector layout 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 side of IP1 • Redundancy • Background rejection (especially beam-gas) LHCC O. Adriani

  5. LHCf location Detectors installed in the TAN region, 140 m away from the Interaction Point, in front of luminosity monitors • Here the beam pipe splits in 2 separate tubes. • Charged particle are swept away by magnets!!! • We will cover up to y LHCC O. Adriani

  6. 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, 32, 38 r.l.) Absorber 22 tungsten layers 7mm – 14 mm thick (W: X0 = 3.5mm, RM = 9mm) 16 scintillator layers (3 mm thick) Trigger and energy profile measurements Energy LHCC O. Adriani

  7. Detector # 2 We used LHC style electronics and readout Impact point(h) 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 directions) 16 scintillator layers (3 mm thick) Trigger and energy profile measurements Absorber 22 tungsten layers 7mm – 14 mm thick (2-4 r.l.) (W: X0 = 3.5mm, RM = 9mm) Energy LHCC O. Adriani

  8. 90mm 290mm Arm#2 Detector Arm#1 Detector Final Detectors ready since 2007 LHCC O. Adriani

  9. Installation • Final installation was completed in January 2008 • No major problems have been found • Quartz fiber for laser calibration has been re-installed • Both Arm1 and Arm2 are working fine • No additional noise is found in the detectors, despite 200 m long power lines and signal cables (for the scintillators) LHCC O. Adriani

  10. LHCf Luminosity Monitor (BRAN) ATLAS ZDC Detectors in place • Installation performed in two phases: • Pre-Installation (2007) • Baking out of the beam pipe (200 °C) • Final Installation (Jan 2008) LHCC O. Adriani

  11. Front Counter • 2 fixed Front Counters were installed in front of Arm1 and Arm2 • They will not move with Arm1 and Arm2 • They are segmented in 2 x and 2 y slices • Very useful to check the beam quality and hence decide to move Arm1 and Arm2 in the operating position from the ‘garage’ position LHCC O. Adriani

  12. After the installation…. • After the installation was completed, a lot of work on: • DAQ • New VME board to increase DAQ rate up to > 1 KHz • Integration of all the subsystem (Using MIDAS frame) • Analyzer to check the data quality and online monitor • Slow control software to control and monitor: • Power supplies • Manipulator • Temperature monitor • LHC interface • New NIM style board (CIBU) to send ‘PERMIT’ to LHC (KILL the beam in case of high rate) • Handhshaking software signals (DIP standard) for Injection, Adjust and Beam Dump • LHCf Physics information (beam position, rate, background etc.) LHCC O. Adriani

  13. Synchronization with Atlas • To have the possibility to identify the events common with Atlas we implemented a synchronization method based on the L1A signal generated by Atlas. • We receive Atlas L1A and we store the time stamp of this signal in our DAQ system. • We can really correlate the Atlas events with the LHCf ones! Atlas Bunch ID – LHCf Bunch Id LHCC O. Adriani

  14. LHCf Detector Silicon Tracker Moving Table An Update on the 2007 SPS Beam Test • Test was very successful!!!! • Energy calibration of the calorimeters • Spatial resolution of the tracking systems Results were partially published on JINST: 2008 JINST 3 S08006 • CERN : SPS T2 H4 • August/September 2007 • Incident Particles • Proton150,350 GeV/c • Electron 50, 100, 150, 200 GeV/c • Muon 150 GeV/c Setup Trigger Scintillator LHCC O. Adriani

  15. Energy Resolution 2 x 2 cm2 tower 2.5 x 2.5 cm2 tower Energy resolution < 3% even for the smallest tower! LHCC O. Adriani

  16. 40mm 20mm Calorimeters Shower Profile @ First SciFi Layer Egamma=46GeV Egamma=18GeV Y X Y X p0 reconstruction g 350 GeV Proton beam Not in scale! g Carbon target (3 cm) in the slot used for beam monitor 9.15 m Arm1 • >107 proton on target (special setting from the SPS people) • Dedicated trigger on both towers of the calorimeter has been used LHCC O. Adriani

  17. p0 mass reconstruction  250 p0 events triggered (in a quite big background) and on disk Preliminary!!!! (MeV) • Main problems: • low photon energy (≥20 GeV) • Direct protons in the towers • Multi hits in the same tower Dm ~ 8 MeV Dm/m ~ 6% LHCC O. Adriani

  18. ARM1 Position resolution 200 GeV electrons sx=172mm Number of event σx[mm] x-pos[mm] E[GeV] σy[mm] sy=159 mm Number of event y-pos[mm] E[GeV] LHCC O. Adriani

  19. ARM2 Position Resolution 200 GeV electrons sx=40 mm x-pos[mm] sy=64 mm y-pos[mm] Alignment has been taken into account LHCC O. Adriani

  20. From the 2007 SPS beam test analysis we can conclude that the detectors fulfill the requirements to reach the physics goals indicated in the TDR LHCC O. Adriani

  21. Preparation for data taking The LHCf control room has been prepared and fully equipped in the Atlas area Furnitures Telephones Air conditioner Network Computers Printers …… LHCC O. Adriani

  22. Dummy event LHCC O. Adriani

  23. Important for machine tuning! Communications with LHC LHCf sends signals to LHC through the DIP system. Link have been tested and it works fine! • Experimental status (On/Off, Gain, etc.) • Detector position (Garage/Operating, position in mm, etc.) • Luminosity rate (Single and Double Arm) • Front Counter rate (single Arm, double Arm coincidence) • Small tower rate (single Arm) • Big tower rate (single Arm) • Double Arm coincidence rate (FC.AND.Towers in opposite sides) • Horizontal and Vertical position of the Beam (every 10000 events or in the whole RUN) • Injection Inhibit • Handshaking signals (Injection, Adjust, Beam Dump) LHCC O. Adriani

  24. We are ready for data taking • On September 10 we observed some signals on Front Counters, with Arm1 and Arm2 in garage position for safety reasons • That day the Atlas BPTX signal was still not available (no info on the real bunches in the Atlas zone) • On September 11 Atlas gave us the synchronized BPTX signals, and we could take Front Counter data by using this signal (still in garage position) • We are measuring Beam-Gas from the Beam2 on Arm1 side LHCC O. Adriani

  25. Front Counter signals LHCC O. Adriani

  26. Conclusions • A lot of work has been done in 2008 • Installation completed • Preparation for running completed • Identification of events common to Atlas and LHCf is ok • First beam gas events acquired • We are ready to send our info to LHC for beam tuning LHCC O. Adriani

  27. Spare slides

  28. 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: K.Fukui,Y.Itow, T.Mase, K.Masuda,Y.Matsubara, H.Menjo,T.Sako, K.Taki, H. Watanabe Waseda University: K. Kasahara, M. Mizuishi, Y.Shimizu, S.Torii Konan University: Y.Muraki Kanagawa University Yokohama: T.Tamura Shibaura Institute of Technology: K. Yoshida ITALY Firenze University and INFN: O.Adriani,, L.Bonechi, M.Bongi, G.Castellini, R.D’Alessandro, P.Papini, S. Ricciarini, A. Viciani Catania University and INFN: A.Tricomi LHCC O. Adriani

  29. Radiation Damage Studies Scintillating fibers and scintillators • Expected dose: 100 Gy/day at 1030 cm-2s-1 • Few months @ 1030 cm-2s-1: 10 kGy • 50% light output • Continous monitor and calibration with Laser system!!! 30 kGy LHCC O. Adriani

  30. LHCf : Monte Carlo discrimination 106 generated LHC interactions  1 Minute exposure@1029 cm-2s-1 luminosity Discrimination between various models is feasible in a very short time Quantitative discrimination with the help of a properly defined c2 discriminating variable based on the spectrum shape (see TDR for details) 5% Energy resolution LHCC O. Adriani

  31. ‘Analysis’ of Beam Gas events We got 116 FC triggers in 8.275.034 BPTX: Nt=116 2.109 protons/bunch Total # of protons: Np=1.7 x 1016 We try to estimate the gas density r from this rate: Nt=Np* L * s * r L=effective lenght ~ 100 m s=Cross section ~ 80 mbarn = 80 x 10-31 m2 We find: r = 8.5 x 1012 H/m3 = 4.2 x 1012 H2/m3 From the LHC Project Report #783: r = 1012 H2/m3 From the pressure measurement in April 2008: r~ 1012 H2/m3 ~ CONSISTENT!!!!!!!!!!!!! LHCC O. Adriani

  32. beam-beam pipe  E γ(signal) > 200 GeV, OK background < 1% beam-gas  It depends on the beam condition background < 1% (under 10-10 Torr) beam halo-beam pipe  It has been newly estimated from the beam loss rate Background < 10% (conservative value) Estimate of the background LHCC O. Adriani

  33. LHCf performances: p0 geometrical acceptance Arm #1 Arm #2 LHCC O. Adriani

  34. LHCf performances: energy spectrum of p0 Typical energy resolution of gis 3 % at 1 TeV LHCC O. Adriani

  35. Transverse projection in TAN slot ARM1: Maximization of the acceptance for vertical beam displacement (crossing angle>0) ARM2: Maximization of the acceptance in R (distance from beam center) LHCC O. Adriani

  36. LHCf: model dependence of neutron energy distribution Original n energy 30% energy resolution LHCC O. Adriani

  37. Energy Resolution Monte Carlo Test Beam N Particles Distance from Edge Energy distribution is corrected for leakage MC predicts that the leakage is energy independent! LHCC O. Adriani

  38. Simulation vs Data 150 GeV m Energy released in the 4° scintillation layer Simulation is very well understood! 100 GeV e- LHCC O. Adriani

  39. While waiting for collisions…. Proton A short comment on new models:PICCO, EPOSVery big interest in LHCf data and in this physics field Drescher, Physical Review D77, 056003 (2008) p0 Neutron LHCC O. Adriani

  40. ARM2-Silicon Energy Resolution 200 GeV electrons SPS beam test data DE/E ~ 12% Total energy measured in silicon (ADC) By looking only at the silicon energy measured, we have an energy resolution ~ 10%!!!!! We can use it as a check for the radiation damage of the scintillators LHCC O. Adriani

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