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

24 Settembre 2008LHCC O. Adriani LHCf Physics Topics – Short summary! Experimental measurement: Experimental measurement: –Precise measurement of  and  0 spectra in the very forward region at LHC 7 TeV + 7 TeV in the c.m. frame  eV in the laboratory frame: 7 TeV + 7 TeV in the c.m. frame  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? 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

24 Settembre 2008LHCC O. Adriani 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

24 Settembre 2008LHCC O. Adriani LHCf: location and detector layout INTERACTION POINT IP1 (ATLAS) Beam line Detector II TungstenScintillator Silicon  strips Detector I TungstenScintillator Scintillating fibers 140 m Detectors should measure energy and position of  from  0 decayse.m. calorimeters with position sensitive layers Two independent detectors on both side of IP1 Redundancy Redundancy Background rejection (especially beam-gas) Background rejection (especially beam-gas)

24 Settembre 2008LHCC O. Adriani 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  

24 Settembre 2008LHCC O. Adriani Detector #1 16 scintillator layers (3 mm thick) Trigger and energy profile measurements Absorber 22 tungsten layers 7mm – 14 mm thick (W: X 0 = 3.5mm, R M = 9mm) 4 pairs of scintillating fiber layers for tracking purpose (6, 10, 32, 38 r.l.) Energy Impact point (  ) 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

24 Settembre 2008LHCC O. Adriani Detector # 2 4 pairs of silicon microstrip layers (6, 12, 30, 42 r.l.) for tracking purpose (X and Y directions) We used LHC style electronics and readout 16 scintillator layers (3 mm thick) Trigger and energy profile measurements Absorber 22 tungsten layers 7mm – 14 mm thick (2-4 r.l.) (W: X 0 = 3.5mm, R M = 9mm) 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 Energy Impact point (  )

24 Settembre 2008LHCC O. Adriani Final Detectors ready since 2007 Arm#1 Detector Arm#2 Detector 90mm 290mm

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

24 Settembre 2008LHCC O. Adriani Detectors in place LHCf Luminosity Monitor (BRAN) Monitor (BRAN) ATLAS ZDC Installation performed in two phases: 1.Pre-Installation (2007) Baking out of the beam pipe (200 °C) Baking out of the beam pipe (200 °C) 2.Final Installation (Jan 2008)

24 Settembre 2008LHCC O. Adriani Front Counter 2 fixed Front Counters were installed in front of Arm1 and Arm2 2 fixed Front Counters were installed in front of Arm1 and Arm2 They will not move with Arm1 and Arm2 They will not move with Arm1 and Arm2 They are segmented in 2 x and 2 y slices 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 Very useful to check the beam quality and hence decide to move Arm1 and Arm2 in the operating position from the ‘garage’ position

24 Settembre 2008LHCC O. Adriani After the installation…. After the installation was completed, a lot of work on: After the installation was completed, a lot of work on: –DAQ New VME board to increase DAQ rate up to > 1 KHzNew VME board to increase DAQ rate up to > 1 KHz Integration of all the subsystem (Using MIDAS frame)Integration of all the subsystem (Using MIDAS frame) Analyzer to check the data quality and online monitorAnalyzer to check the data quality and online monitor –Slow control software to control and monitor: Power suppliesPower supplies ManipulatorManipulator Temperature monitorTemperature monitor –LHC interface New NIM style board (CIBU) to send ‘PERMIT’ to LHC (KILL the beam in case of high rate)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 DumpHandhshaking software signals (DIP standard) for Injection, Adjust and Beam Dump LHCf Physics information (beam position, rate, background etc.)LHCf Physics information (beam position, rate, background etc.)

24 Settembre 2008LHCC O. Adriani 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. 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 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! We can really correlate the Atlas events with the LHCf ones! Atlas Bunch ID – LHCf Bunch Id

24 Settembre 2008LHCC O. Adriani An Update on the 2007 SPS Beam Test LHCfDetectorSilicon Tracker Tracker Moving Table TriggerScintillator CERN : SPS T2 H4 CERN : SPS T2 H4 August/September 2007 August/September 2007 Incident Particles Incident Particles –Proton 150,350 GeV/c –Electron 50, 100, 150, 200 GeV/c –Muon 150 GeV/c Setup Test was very successful!!!! Energy calibration of the calorimeters Energy calibration of the calorimeters Spatial resolution of the tracking systems Spatial resolution of the tracking systems Results were partially published on JINST: 2008 JINST 3 S08006

24 Settembre 2008LHCC O. Adriani Energy Resolution 2.5 x 2.5 cm 2 tower 2 x 2 cm 2 tower Energy resolution < 3% even for the smallest tower!

24 Settembre 2008LHCC O. Adriani  0 reconstruction 9.15 m   350 GeV Proton beam Carbon target (3 cm) in the slot used for beam monitor Arm1 Not in scale! E gamma =18GeV Shower First SciFi Layer Calorimeters 20mm X 40mm X Y Y E gamma =46GeV >10 7 proton on target (special setting from the SPS people) Dedicated trigger on both towers of the calorimeter has been used Dedicated trigger on both towers of the calorimeter has been used

24 Settembre 2008LHCC O. Adriani  0 mass reconstruction (MeV) Preliminary!!!!  250  0 events triggered (in a quite big background) and on disk Main problems: Main problems: –low photon energy (≥ 20 GeV) –Direct protons in the towers –Multi hits in the same tower  m ~ 8 MeV  m/m ~ 6%

24 Settembre 2008LHCC O. Adriani ARM1 Position resolution σ x [mm] σ y [mm] Number of event x-pos[mm] y-pos[mm] 200 GeV electrons  x =172  m  y =159  m E[GeV]

24 Settembre 2008LHCC O. Adriani ARM2 Position Resolution  x =40  m x-pos[mm] y-pos[mm] 200 GeV electrons  y =64  m Alignment has been taken into account

24 Settembre 2008LHCC O. Adriani 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

24 Settembre 2008LHCC O. Adriani Preparation for data taking FurnituresTelephones Air conditioner NetworkComputersPrinters…… The LHCf control room has been prepared and fully equipped in the Atlas area

24 Settembre 2008LHCC O. Adriani Dummy event

24 Settembre 2008LHCC O. Adriani Communications with LHC Experimental status (On/Off, Gain, etc.) Experimental status (On/Off, Gain, etc.) Detector position (Garage/Operating, position in mm, etc.) Detector position (Garage/Operating, position in mm, etc.) Luminosity rate (Single and Double Arm) 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 events or in the whole RUN) Horizontal and Vertical position of the Beam (every events or in the whole RUN) Injection Inhibit Injection Inhibit Handshaking signals (Injection, Adjust, Beam Dump) Handshaking signals (Injection, Adjust, Beam Dump) LHCf sends signals to LHC through the DIP system. Link have been tested and it works fine! Important for machine tuning!

24 Settembre 2008LHCC O. Adriani 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 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) 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 We are measuring Beam-Gas from the Beam2 on Arm1 side

24 Settembre 2008LHCC O. Adriani Front Counter signals

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

Spare slides

24 Settembre 2008LHCC O. Adriani The LHCf Collaboration 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 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 SPAIN IFIC Valencia: A.Fauss, J.Velasco FRANCE Ecole Politechnique Paris: M. Haguenauer USA LBNL Berkeley: W. Turner CERN D.Macina, A.L. Perrot

24 Settembre 2008LHCC O. Adriani Radiation Damage Studies 30 kGy Expected dose: 100 Gy/day at cm -2 s -1 Expected dose: 100 Gy/day at cm -2 s -1 Few cm -2 s -1 : 10 kGy Few cm -2 s -1 : 10 kGy 50% light output 50% light output Continous monitor and calibration with Laser system!!! Continous monitor and calibration with Laser system!!! Scintillating fibers and scintillators

24 Settembre 2008LHCC O. Adriani LHCf : Monte Carlo discrimination 10 6 generated LHC interactions  1 Minute 29 cm -2 s -1 luminosity Discrimination between various models Discrimination between various models is feasible in a very short time is feasible in a very short time Quantitative discrimination with the help of a properly defined  2 discriminating variable based on the spectrum shape (see TDR for details) 5% Energy resolution

24 Settembre 2008LHCC O. Adriani ‘Analysis’ of Beam Gas events We got 116 FC triggers in BPTX: N t = protons/bunch Total # of protons: N p =1.7 x We try to estimate the gas density  from this rate: N t =N p * L *  *  L=effective lenght ~ 100 m  =Cross section ~ 80 mbarn = 80 x m 2 We find:  = 8.5 x H/m 3 = 4.2 x H 2 /m 3 From the LHC Project Report #783:  = H 2 /m 3 From the pressure measurement in April 2008:  ~ H 2 /m 3 ~ CONSISTENT!!!!!!!!!!!!!

24 Settembre 2008LHCC O. Adriani Estimate of the background beam-beam pipe beam-beam pipe  E γ (signal) > 200 GeV, OK  E γ (signal) > 200 GeV, OK background < 1% beam-gas beam-gas  It depends on the beam condition  It depends on the beam condition background < 1% (under Torr) beam halo-beam pipe beam halo-beam pipe  It has been newly estimated from the beam loss rate  It has been newly estimated from the beam loss rate Background < 10% (conservative value) Background < 10% (conservative value)

24 Settembre 2008LHCC O. Adriani LHCf performances :  0 geometrical acceptance Arm #1 Arm #2

24 Settembre 2008LHCC O. Adriani LHCf performances: energy spectrum of  0 Typical energy resolution of  is 3 % at 1 TeV

24 Settembre 2008LHCC O. Adriani ARM1: Maximization of the acceptance for vertical beam displacement (crossing angle>0) ARM2: Maximization of the acceptance in R (distance from beam center) Transverse projection in TAN slot

24 Settembre 2008LHCC O. Adriani LHCf: model dependence of neutron energy distribution Original n energy 30% energy resolution

24 Settembre 2008LHCC O. Adriani Energy Resolution Monte Carlo Energy distribution is corrected for leakage Distance from Edge N Particles MC predicts that the leakage is energy independent! Test Beam

24 Settembre 2008LHCC O. Adriani Simulation vs Data Energy released in the 4° scintillation layer Simulation is very well understood! 100 GeV e GeV 

24 Settembre 2008LHCC O. Adriani While waiting for collisions …. Drescher, Physical Review D77, (2008) (2008) A short comment on new models: PICCO, EPOS Very big interest in LHCf data and in this physics field Neutron 0000 Proton

24 Settembre 2008LHCC O. Adriani ARM2-Silicon Energy Resolution  E/E ~ 12% Total energy measured in silicon (ADC) 200 GeV electrons SPS beam test data 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