1. March 22, 2006LHCf Technical Design ReportO. Adriani LHCf Technical Design Report CERN-LHCC-2006-004 LHCF-TDR-001 7 February 2006 Measurement of Photons and Neutral Pions in the Very Forward Region of LHC O. Adriani(1), L. Bonechi(1), M. Bongi(1), R. D’Alessandro(1), D.A. Faus(2), M. Haguenauer(3), Y. Itow (4), K. Kasahara(5), K. Masuda(4), Y. Matsubara(4), H. Menjo(4), Y. Muraki(4), P. Papini(1), T. Sako(4), T. Tamura(6), S. Torii(7), A. Tricomi(8), W.C. Turner(9), J. Velasco(2), K. Yoshida(6) The LHCf collaboration (1) INFN Firenze, Univ. di Firenze, Firenze, Italy (2) IFIC, Centro Mixto CSIC-UVEG, Valencia, Spain (3) Ecole-Polytechnique, Paris, France (4) STE laboratory, Nagoya University, Nagoya, Japan (5) Shibaura Institute of Technology, Saitama, Japan (6) Kanagawa University, Yokohama, Japan (7) RISE, Waseda Univ., Tokyo, Japan (8) INFN Catania, Univ. di Catania, Catania, Italy (9) LBNL, Berkeley, California, USA

2. March 22, 2006LHCf Technical Design ReportO. Adriani Highlight of the talk 1.Short ‘history’ 2.Review of physics 3.Detector overview and background study (after November 16 th LHCC) 4.Progress report on cabling, safety, installation, trigger, luminosity measurement, etc 5.Possible running scenario 6.Summary Many important technical aspects can not be covered in this presentation  TDR for details

3. March 22, 2006LHCf Technical Design ReportO. Adriani Letter Of Intent: May 2004 Technical report: September 2005 Technical Design Report: February 2006 The physics goals are worthwhile and the proposed experiment appears suited to achieve them A few key issues require immediate consideration, and documentation in the update of the TP: establish official contact with the relevant structures in the AT/AB departments, as well as in ATLAS etc… appoint a technical coordinator (possibly located at CERN?) consider and document safety issues On the other hand: the TP is not sufficiently detailed and fails to provide a solid and compelling evidence that the above expectations are justified LHCC October 2005 comments: TDR was released to answer to these questions

4. March 22, 2006LHCf Technical Design ReportO. Adriani Main problems in High Energy Cosmic Rays (E>10 15 eV) 1.Composition X max (g/cm 2 ) Energy (eV) 2.Spectrum / GZK Cutoff

5. March 22, 2006LHCf Technical Design ReportO. Adriani The dominant contribution to the energy flux is in the very forward region (   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) Development of atmospheric showers Simulation of an atmospheric shower due to a 10 19 eV proton. The direct measurement of the  production cross section as function of p T is essential to correctly estimate the energy of the primary cosmic rays (LHC: 10 17 eV)

6. March 22, 2006LHCf Technical Design ReportO. Adriani INTERACTION POINT Beam line Detector II Tungsten Scintillator Silicon  strips Detector I Tungsten Scintillator Scintillating fibers 140 m 1.Redundancy 2.Background rejection (especially beam-gas) Experimental Method: 2 independent detectors on both sides of IP IP1 was definitely chosen in October 2005

7. March 22, 2006LHCf Technical Design ReportO. Adriani Here the beam pipe splits in 2 separate tubes. Charged particle are swept away by magnets!!! We will cover up to y  Detectors will be installed in the TAN region, 140 m away from the Interaction Point, in front of luminosity monitors

8. March 22, 2006LHCf Technical Design ReportO. Adriani The TAN and LHCf marble shielding manipulator boxes for DAQ electronic box ~ (15 × 15 × 40) cm 3

9. March 22, 2006LHCf Technical Design ReportO. Adriani ARM #1 detector scintillators tungsten layers scintillating fibers - 2 towers (2.0  2.0cm 2 and 4.0  4.0 cm 2 ) ~47 r.l. (22  2.1 r.l. tungsten layers) 16 scintillator layers (3 mm thick) - 4 pairs of scintillating fiber layers for tracking purpose (two orthogonal directions) Energy Impact point (  )

10. March 22, 2006LHCf Technical Design ReportO. Adriani ARM #2 detector silicon layers scintillators tungsten layers - 2 towers (2.5  2.5cm 2 and 3.5  3.5 cm 2 ) 44 r.l. (22  2 r.l. tungsten layers) 16 scintillator layers (3 mm thick) - 4 pairs of silicon microstrip layers for tracking purpose (X and Y directions) Energy Impact point (  ) See TDR for details… We used LHC style electronics and readout

11. March 22, 2006LHCf Technical Design ReportO. Adriani Transverse projection of detector #1 in the TAN slot

12. March 22, 2006LHCf Technical Design ReportO. Adriani Transverse projection of detector #2 in the TAN slot

13. March 22, 2006LHCf Technical Design ReportO. Adriani LHCf physics measurements 1.Single photon spectrum  0 fully reconstructed (1  in each tower)  0 reconstruction is an important tool for energy calibration (  0 mass constraint) Basic concept: minimum 2 towers (  0 reconstruction) Smallest tower on the beam (multiple hits) Dimension of the tower  Moliere radius Maximum acceptance (given the LHC constraints) Simulation is used to understand the physics performances Beam test in Summer 2004 (Energy resolution)

14. March 22, 2006LHCf Technical Design ReportO. Adriani Development of showers in Arm #2 E γ = 500 GeV Fluka based simulation

15. March 22, 2006LHCf Technical Design ReportO. Adriani Position resolution of Arm #2 calorimeter 7  m for 1.8 TeV photons

16. March 22, 2006LHCf Technical Design ReportO. Adriani Single  geometrical acceptance Some runs with LHCf vertically shifted few cm will allow to cover the whole kinematical range

17. March 22, 2006LHCf Technical Design ReportO. Adriani Acceptance map on P T  -E γ plane Detectable events 140 Beam crossing angle A vertical beam crossing angle > 0 will increase the acceptance of LHCf

18. March 22, 2006LHCf Technical Design ReportO. Adriani Monte Carlo  ray energy spectrum (5% Energy resolution is taken into account) 10 6 generated LHC interactions  1 minute exposure Discrimination between various models is feasible Quantitative discrimination with the help of a properly defined  2 discriminating variable based on the spectrum shape (see TDR for details)

19. March 22, 2006LHCf Technical Design ReportO. Adriani  0 geometrical acceptance Arm #1 Arm #2

20. March 22, 2006LHCf Technical Design ReportO. Adriani Energy spectrum of π 0 expected from different models (Typical energy resolution of  is 3 % at 1TeV)

21. March 22, 2006LHCf Technical Design ReportO. Adriani  0 mass resolution Arm #1  E/E=5% 200  m spatial resolution  m/m = 5%

22. March 22, 2006LHCf Technical Design ReportO. Adriani Model dependence of neutron energy distribution Original n energy 30% energy resolution

23. March 22, 2006LHCf Technical Design ReportO. Adriani Results of the beam test at H4 line

24. March 22, 2006LHCf Technical Design ReportO. Adriani Summary 1 We will be able to measure π 0 mass with ±5% resolution. We will be able to distinguish the models by measurements of π 0 and γ We will be able to distinguish the models by measurements of n Beam crossing angle ≠0 and/or vertical shifts of LHCf by few cm will allow more complete physics measurements

25. March 22, 2006LHCf Technical Design ReportO. Adriani Estimation of the background beam-beam pipe  answered (on Nov.16), E γ (signal) > 200 GeV, OK background < 1% (see details in TDR) beam-gas  answered (on Nov.16) It depends on the beam condition background < 1% (under 10 -10 Torr)(see details in TDR) beam halo-beam pipe  It has been newly estimated from the beam loss rate Background < 10% (conservative value)(see details in TDR)

26. March 22, 2006LHCf Technical Design ReportO. Adriani Background from the beam pipe

27. March 22, 2006LHCf Technical Design ReportO. Adriani

28. March 22, 2006LHCf Technical Design ReportO. Adriani Support from CERN for Integration We had (and we will have!) continuous meetings with CERN teams General : TS/LEA Integration: TS/IC Cabling: TS/EL Cooling: TS/CV Survey (cabling): TS/SU Safety: SG Radiation protection: SC/RP ATLAS, BRAN, ZDC teams Engineering Change Request (ECR) has been submitted and approved last week: Machine people are well informed about LHCf No problems foreseen for the LHCf installation at the LHC startup Main item to be discussed is the BRAN (LUMI) interference (see later) Takashi Sako: Technical coordinator A very useful TAN integration workshop has been organized on March 10 at CERN (TS/LEA). All the involved groups were present!!!!

29. March 22, 2006LHCf Technical Design ReportO. Adriani Rack, data taking and trigger *Two racks will be located at Y26-05.A1 and Y27-05.A1 at USA15 hall of ATLAS counting room *The trigger signal will be created after 1.4  sec of the beam crossing 1 st level trigger 2 nd level trigger

30. March 22, 2006LHCf Technical Design ReportO. Adriani Cables TS/LEA is fully aware of the cables stuff Demande Installation Cable (DIC) has been submitted The order is under way Cables will be pulled in the July-September period See TDR for details

31. March 22, 2006LHCf Technical Design ReportO. Adriani Radiation Safety We have estimated the total radiation dose and activation of LHCf installed in the TAN The activation after 30 days of operation and 1 day cool-down at ℒ ≈ 10 30 /cm -2 sec -1 is 10 -3 – 10 -2 mSV/hr Remote handling procedures may not be needed We are in contact with SC/RP peoples

32. March 22, 2006LHCf Technical Design ReportO. Adriani Installation plan A detailed installation plan has been agreed with TS/LEA Arm #1: 128 days from May 2006 to November 2006 Cables tray Cables Detector Manipulator Electronics Tests Arm #2: 210 days from May 2006 to February 2007, similar to #1 LHCf Arm #1 and #2 will be ready to take the first LHC data….. (Beam test of the complete Arm #1 and part of the Arm #2 is foreseen August 24 th, September 3 rd at SPS)

33. March 22, 2006LHCf Technical Design ReportO. Adriani LHCf and LUMI monitor (BRAN) LUMI monitor (BRAN) inside TAN is beyond LHCf (replacing 4th copper bar) LHCf Lumi Cu Bar / ZDC IP1 LHCf Lumi Cu Bar / ZDC LHCf  44 X 0 thickness But the thickness is not uniform (diamond shaped towers, no material outside towers) LUMI Monitor see different thickness of material in different geometrical regions  different response as function of the impact point position (calibration is required) reduction of the number of neutral particles hitting BRAN possible dependence of the detector response as function of the beam position? We are studying the problem of the LHCf effect on LUMI together with W.C. Turner and his group from LBNL. CERN LHC and ATLAS people are informed about these studies (see TAN integration workshop as last example)

34. March 22, 2006LHCf Technical Design ReportO. Adriani 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?) Answer:  If beam displacement is < a few mm, difference is < 10%  LHCf itself can provide the center of neutral flux  LHCf can give some info on Luminosity measurement

35. March 22, 2006LHCf Technical Design ReportO. Adriani reduction factor for BRAN: # of neutral hadrons in the LHCf aperture / # of neutral hadrons in the whole aperture (inelastic interactions generated with DPMJET3 model) Typical reduction factor: 0.3 BRAN response vs beam position H.Menjo Arm #1Arm #2

36. March 22, 2006LHCf Technical Design ReportO. Adriani 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 (2) 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

37. March 22, 2006LHCf Technical Design ReportO. Adriani Determination of neutral flux center by LHCf LHCf can measure (and provide to LHC) the center of neutral flux from the collisions Position sensitive layers particles If the center of the neutral flux hits LHCf  << 1 mm resolution Beam test result  ~ 200  m

38. March 22, 2006LHCf Technical Design ReportO. Adriani Summary 2 LHCf can do the proposed physics measurements (background is under control) Integration with CERN infrastructures and other groups involved is well established The interference with BRAN/LUMI measurement is under study; a ‘smooth’ solution seems to be feasible LHCf can provide on-line useful information to machine people (Relative luminosity, beam position, beam-gas rate etc.) Important issue to be considered in detail from now on

39. March 22, 2006LHCf Technical Design ReportO. Adriani Optimal LHCf run conditions Beam parameters used for commissioning are good for LHCf!!! Beam parameterValue # of bunches ≤ 43 Bunch separation > 2  sec Crossing angle 0 rad 140  rad downward Luminosity per bunch < 2 x 10 28 cm -2 s -1 Luminosity < 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 )

40. March 22, 2006LHCf Technical Design ReportO. Adriani From H. Burkhardt TAN workshop presentation

41. March 22, 2006LHCf Technical Design ReportO. Adriani LHCf possible running scenario Phase-I – Parasite running during the early stage of LHC commissioning in 2007 – Remove the detector when luminosity reaches 10 30 cm -2 s -1 level for radiation reason and reinstall the 3 Cu bars (no activation problems) Phase-II –Re-install the detector at the next opportunity of low luminosity run after removal of Cu bars (activated to 10 -1 mSv/hr, manipulator?) Phase-III –Future extension for p-A, A-A run with upgraded detectors. Detailed running scenario should be discussed and agreed with LHCC, Machine people, Atlas people….

42. March 22, 2006LHCf Technical Design ReportO. Adriani Budget share table Detector # 1 Detector#2 TungstenJapan Japan Mechanics Japan Japan Plastic Scintillators Japan Japan Scintillating fibers Japan ----------- Silicon sensors ----------- INFN Photomultipliers for scintillator Japan Japan Multianode photomultipliers for fibers Japan ----------- Preamplifiers for silicon ----------- INFN Hybrid and Kapton for silicon ----------- INFN Readout electronics for fibers (VA based) Japan ----------- Readout electronics for silicon ----------- INFN VME Interface board for fibers Japan ----------- VME Interface board for silicon ----------- INFN VME ADC boards for scintillators Japan/INFN Japan/INFN VME crate Japan INFN Low voltage Power Supply Japan INFN High voltage Power Supply for scintillators Japan Japan/INFN High voltage Power Supply for fibers Japan ----------- Contributions from different countries Japan: 600KCHF Italy:300KCHF France: under negotiation

43. March 22, 2006LHCf Technical Design ReportO. Adriani Concluding Remarks LHCf physics measurements are extremely useful for cosmic ray physics (see LOI 2004) A huge work has been done to complete the TDR, answering to the LHCC and referees comments The detectors have been carefully optimized The integration with other activities possibly interfering with LHCf is well established (ATLAS, BRAN/LUMI, TAN related experiment, safety, cabling etc.) ECR has been approved last week LHCf will be ready to take the first LHC data…