1. Alessia Tricomi University and INFN Catania on behalf of the LHCf Collaboration The LHCf experiment at LHC ISVHECRI08 - XV International Symposium on Very High Energy Cosmic Ray Interactions Paris 1 – 6 September, 2008 Experiment goals Experiment goals The LHCf detector The LHCf detector Physics performance Physics performance Running plan Running plan

2. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 The LHCf Collaboration ITALY Firenze University and INFN: O.Adriani,, L.Bonechi, M.Bongi, G.Castellini, R.DAlessandro, 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

3. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 LHCf: modelling Cosmic Rays at LHC Astrophysical parameters - source type - source distribution - source spectrum - source composition - propagation LHC Forward Physics - cross section - particle spectra (E, P T, θ, η, X F ) (E, P T, θ, η, X F ) Nuclear Interaction - calibration with data of Monte Carlo used in Cosmic Ray Physics

4. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 The Cosmic Ray Spectra Based on data presented at the 30 th ICRC Merida (Mexico) Figure prepared by Y. Tokanatsu super GZK events?!? GZK cutoff: 10 20 eV p (2.7K) N p (2.7K) N Different results between different experiments

5. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 The Cosmic Ray Spectra Difference in the energy scale between different experiments??? AGASA x 0.9 HiRes x1.2 Yakutsk x 0.75 Auger x1.2 (not enough) Berezisky 2007 AGASA Systematics Total ±18% Hadron interaction (QGSJET, SIBYLL) ~10% (QGSJET, SIBYLL) ~10% (Takeda et al., 2003) (Takeda et al., 2003)

6. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 Cosmic Ray Composition Not only GZK… Different interaction models lead different conclusions about the composition of the primary cosmic rays. IRON PROTON Knapp et al., 2003 Energy (eV) X max (g/cm 2 )

7. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 Cosmic Ray Composition X max favors heavy primary Anisotropy favors light primary (if accept AGN correlation)

8. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 Cosmic Ray Composition QGSJET01 SIBYLL 2.1 Kascade Results

9. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 Need for calibration… Composition: inferred from X max Spectrum: Energy is measured by counting the secondaries Simulation plays a crucial role LHCf is a tool to calibrate the simulation

10. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 Development of atmospheric showers The dominant contribution to the energy flux is in the very forward region ( 0) Simulation of an atmospheric shower due to a 10 19 eV proton. No cut : X F <0.05 : X F <0.05, K: X F <0.1, K: X F <0.1 X F ~E/E 0 In this forward region the highest energy available measurements of 0 cross section were done by UA7 (E=10 14 eV, y= 5÷7)

11. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 Forward Physics at LHC LHC LHCf firstly proposed to use LHC, the highest energy accelerator 14 TeV in the center of mass E lab =10 17 eV (E lab = E 2 cm /2 m P ) to calibrate MC simulation code LHC Tevatron A 100 PeV fixed-target interaction with air has the cm energy of a pp collision at the LHC AUGER Cosmic ray spectrum

12. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 But… Charged particles Neutral particles Beam pipe General purpose detectors (ATLAS, CMS,…) cover only the central region Special detectors to access forward particles are necessary

13. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 How to access Very Forward Physics at LHC? Charged particles Neutral particles Beam pipe Surrounding the beam pipe with detectors Simple way, but still miss very very forward particles

14. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 Neutral particles Beam pipe Charged particles Install detectors inside the beam pipe Challenging but ideal for charged particle How to access Very Forward Physics at LHC?

15. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 Y shape chamber enables us neutral measurements Zero degree calorimeters Charged particles Neutral particles Beam pipe How to access Very Forward Physics at LHC? LHCf

16. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 Pseudo rapidity in LHC pseudorapidity = - ln (tan /2) pseudorapidity = - ln (tan /2) The CMS and TOTEM diffractive and forward physics working group Transverse energy flow Energy flow LHCf

17. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 The LHC ring 27 km ring ATLASLHCf IP1

18. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 LHCf: location and detector layout INTERACTION POINT IP1 (ATLAS) Beam line Detector II TungstenScintillator Silicon mstrips Detector I TungstenScintillator Scintillating fibers 140 m Detectors should measure energy and position of 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)

19. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 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. Here the beam pipe splits in 2 separate tubes. Charged particle are swept away by magnets!!! Charged particle are swept away by magnets!!! We will cover up to y We will cover up to y

20. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 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

21. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 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 ( )

22. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 Double ARM Detectors Arm#1 Detector Arm#2 Detector 90mm 290mm

23. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 Detectors in place LHCf Luminosity Monitor (BRAN) Monitor (BRAN) ATLAS ZDC Installation performed in two phases: 1.Pre-Installation (Jan/Apr 2007) Baking out of the beam pipe (200 °C) Baking out of the beam pipe (200 °C) 2.Final Installation (Jan 2008)

24. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 LHCf Physics performance 1.Single photon spectrum 2. 0 fully reconstructed (1 g in each tower) 0 reconstruction is an important tool for energy calibration ( 0 mass constraint) 0 reconstruction is an important tool for energy calibration ( 0 mass constraint) Basic detector requirements: minimum 2 towers ( 0 reconstruction) minimum 2 towers ( 0 reconstruction) Smallest tower on the beam (multiple hits) Smallest tower on the beam (multiple hits) Dimension of the tower Moliere radius Dimension of the tower Moliere radius Maximum acceptance (given the LHC constraints) Maximum acceptance (given the LHC constraints) Simulation Beam Test Unfortunately no LHC data still available Results for the moment based on

25. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 Detectable events 140 Beam crossing angle LHCf: acceptance on P T -E plane A vertical beam crossing angle > 0 will increase the acceptance of LHCf

26. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 LHCf single geometrical acceptance Some runs with LHCf vertically shifted few cm will allow to cover the whole kinematical range

27. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 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

28. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 LHCf : Monte Carlo discrimination 10 6 generated LHC interactions 10 6 generated LHC interactions 1 Minute exposure@10 29 cm -2 s -1 luminosity Discrimination between various models Discrimination between various models is feasible is feasible Quantitative discrimination with the help of a properly defined 2 discriminating variable based on the spectrum shape (see TDR for details) 5% Energy resolution

29. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 LHCf: model dependence of neutron energy distribution Original n energy 30% energy resolution

30. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 New Models Drescher, Physical Review D77, 056003 (2008) 056003 (2008) PICCO EPOS Neutron 0 Proton 29

31. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 0 spectra 0 spectra QGSJETII DPMJET3 χ 2 = 106 (C.L. <10 -6 ) DPMJET3 χ 2 = 106 (C.L. <10 -6 ) SIBYLL χ 2 = 83 (C.L. <10 -6 ) SIBYLL χ 2 = 83 (C.L. <10 -6 )DPMJET3 SIBYLL χ 2 = 28 (C.L.= 0.024) SIBYLL χ 2 = 28 (C.L.= 0.024) 10 7 events DOF = 17-2=15 10 7 events DOF = 17-2=15 0 produced at collision can be extracted by using gamma pair events 0 produced at collision can be extracted by using gamma pair events Powerful tool to calibrate the energy scale and also to eliminate beam-gas BG

32. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 Arm #1 E/E=5% E/E=5% 200 m spatial resolution m/m = 5% m/m = 5% LHCf performances: 0 mass resolution

33. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 SPS Beam Test LHCfDetectorSilicon Tracker Tracker Moving Table TriggerScintillator CERN : SPS T2 H4 CERN : SPS T2 H4 2006 Aug. 28 – Sep. 4 2006 Aug. 28 – Sep. 4 Incident Particles Incident Particles –Proton 150,350GeV/c –Electron 100,200GeV/c –Muon 150GeV/c Setup Test was successful Analysis is under way for Energy calibration of the calorimeters Energy calibration of the calorimeters Spatial resolution of the tracking systems Spatial resolution of the tracking systems

34. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 Energy Resolution Monte Carlo SPS bean test Energy distribution is corrected for leakage correction Distance from Edge N Particles MC predicts that the leakage is energy independent!

35. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 0 reconstruction 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 Profile @ 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

36. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 0 mass reconstruction 0 mass reconstruction (MeV) Preliminary!!!! 250 0 events triggered (in a quite big background) and on disk 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

37. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 ARM1 Position resolution σ x [mm] σ [mm] Number of event x-pos[mm] y-pos[mm] E[GeV] 200 GeV electrons σ x =172 m σ y =159 m

38. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 ARM2 Position Resolution Number of event σ x =40 m x-pos[mm] y-pos[mm] 200 GeV electrons σ y =64 m

39. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 ARM2-Silicon Energy Resolution E/E ~ 12% E/E ~ 12% No correction/calibration applied ADC 200 GeV electrons SPS beam test data

40. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 LHC schedule Beam commissiong parameters are good for LHCf! Preferred LHCf run parameters Beam parameter Value # of bunches 43 43 Bunch separation > 2 sec Crossing angle 0 rad 0 rad 140 rad downward Luminosity per bunch < 2 x 10 28 cm -2 s -1 < 2 x 10 28 cm -2 s -1 Luminosity < 10 30 cm -2 s -1 < 10 30 cm -2 s -1 Bunch intensity 4x10 10 ppb ( *=18m) 1x10 10 ppb ( *= 1m)

41. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 Radiation Damage Studies 30 kGy Expected dose: 100 Gy/day at 10 30 cm -2 s -1 Expected dose: 100 Gy/day at 10 30 cm -2 s -1 Few months @ 10 30 cm -2 s -1 : 10 kGy Few months @ 10 30 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

42. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 LHCf possible running scenario Phase-I Phase-I – 900 GeV collision before rumping in 2008 (hope in a week from now!) – 10 TeV run in 2008 during the LHC commissioning (low luminosity) –14 TeV run in 2009 during commissioning –Remove LHCf when luminosity reaches 10 30 cm -2 s -1 for radiation damage reasons Phase-II Phase-II –Re-install the detector at the next opportunity of low luminosity run –Dedicated runs (crossing angle, etc.) Phase-III Phase-III –Future extension for p-A, A-A run with upgraded detectorsare under study

43. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 LHCf: conclusions and plans Compilation of the EAS data is affected by the uncertainty of hadron interaction. Compilation of the EAS data is affected by the uncertainty of hadron interaction. LHCf experiment will provide crucial data of hadron interaction for CR study. LHCf experiment will provide crucial data of hadron interaction for CR study. LHCf can clearly discriminate the existing and new models by measurements of π 0, γ and n thanks to its excellent performances LHCf can clearly discriminate the existing and new models by measurements of π 0, γ and n thanks to its excellent performances –Energy Resolution ~5% –Spatial resolution ~40-200 m –Beam crossing angle 0 and/or vertical shifts of LHCf by few cm will allow more complete physics measurements Both Detectors ready to fulfil the run program Both Detectors ready to fulfil the run program So now

44. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 LHCf: conclusions and plans We need only to wait for LHC beams, which indeed are just arriving! Hoping to answer all our questions

45. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 Back-up slides

46. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 The TAN and LHCf marble shielding manipulator boxes for DAQ electronic box ~ (15 × 15 × 40) cm 3

47. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 Front scintillator: Fixed position wrt to TAN Silicon + Tungsten + Scintillator: Silicon + Tungsten + Scintillator: +/- 5 cm vertical excursion PMTR7400 Front scintillator Lateral view of ARM #2 Si Tracker + Hybrid Beam axis

48. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 rate rate

49. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 rate rate

50. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 QGSJETII: used model QGSJET: c 2 /DOF=107/125 DPMJET3: c 2 /DOF=224/125 SYBILL: c 2 /DOF=816/125 ray energy spectrum for different positions ray energy spectrum for different positions

51. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 e,, p beam Silicon Calorimeter Before correction After correction 2 mm The CERN test beam on August 2004

52. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 Leak Correction Monte Carlo Prototype Experiment MC predicts that the leakage is energy independent! correction Distance from Edge N Particles

53. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 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 10 -10 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)

54. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 Effect of LHCf on BRAN measurement The effect of LHCf on BRAN measurements has been studied in the last months by simulation –Reduction of shower particles at BRAN –Position dependence on beam displacement (question from machine peoples: if we shift by 1 mm the real beam, does the center of the measured neutral energy shifts by 1 mm?) LUMI monitor (BRAN) inside TAN is beyond LHCf (replacing 4th copper bar) LHCf Lumi Cu Bar / ZDC IP1 LHCf Lumi

55. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 Arm #1Arm #2 H.Menjo Relative change of the reduction factors for BRAN with respect to the nominal value (center of the beam: nominal one) BRAN response vs beam position If the position of beam center stays within a few mm from the beam-pipe center, the reduction factors do not change more than 10% 1 x 1 cm 2 1 x 1 cm 2

56. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 LHCf performances: 0 geometrical acceptance Arm #1 Arm #2

57. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 LHCf performances: energy spectrum of 0 Typical energy resolution of is 3 % at 1TeV

58. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 Beam parameters used for commissioning are good for LHCf!!! Beam parameters used for commissioning are good for LHCf!!! Beam parameter Value # of bunches 43 43 Bunch separation > 2 sec Crossing angle 0 rad 0 rad 140 rad downward Luminosity per bunch < 2 x 10 28 cm -2 s -1 < 2 x 10 28 cm -2 s -1 Luminosity < 0.8 x 10 30 cm -2 s -1 < 0.8 x 10 30 cm -2 s -1 Bunch intensity 4x10 10 ppb ( *=18m) 1x10 10 ppb ( *= 1m) ( No radiation problem for 10kGy by a year operation with this luminosity ) Optimal LHCf run conditions

59. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 From R. Bailey presentation at January 2007 TAN workshop Stage 1 Optimal conditions for LHCf running!

60. Alessia Tricomi University & INFN Catania The LHCf experiment at LHC ISVHECRI08, Paris 1-6 September 2008 From R. Bailey presentation at January 2007 TAN workshop