1. 1 F. GrancagnoloILC Workshop Valencia, 8. 11. 2006 ILC Workshop - ECFA and GDE Joint Meeting Valencia, 5-13 November 2006 F. Grancagnolo, INFN - Lecce The Muon System of the 4 th Concept Detector at

2. 2 F. GrancagnoloILC Workshop Valencia, 8. 11. 2006 4 th Concept Detector Layout Triple-readout fiber calorimeter: scintillation/Cerenkov/neutron Muon dual-solenoid iron-free geometry 6.4 m 7.7 m NOVEL FEATURES:

3. 3 F. GrancagnoloILC Workshop Valencia, 8. 11. 2006 TPC  - BARREL   - E C N A D P Dual Solenoid B-field Alexander Mikhailichenko design

4. 4 F. GrancagnoloILC Workshop Valencia, 8. 11. 2006  -System basic element: drift tube radius 2.3 cm filled with 90% He – 10% iC 4 H 10 @ NTP gas gain few × 10 5 total drift time 2 µs primary ionization 13 cluster/cm  ≈ 20 electrons/cm total both ends instrumented with: > 1.5 GHz bandwith 8 bit fADC > 2 Gsa/s sampling rate free running memory for a fully efficient timing of primary ionization: cluster counting accurate measurement of longitudinal position with charge division particle identification with dN cl /dx ASIC chip under development at INFN-LE

5. 5 Cluster Counting full vertical scale = 30 mV (amplification x10) horizontal scale = 500 ns/div sampling rate = 2.5 Gsa/s 2 cm tube gas: 90% He + 10% iC 4 H 10 N cl = 13./cm N ele = 20./ cm Max drift time 1.3  s 50 ns 5 mV left right trigger Cosmic ray triggered by scintillators telescope and read out by a digital sampling scope: 8 bit, 4 GHz, 2.5 Gsa/s Amplifier bandwith: 1.8 GHz, gain ×10 t0t0 t last t first 1.3  s F. GrancagnoloILC Workshop Valencia, 8. 11. 2006 t0t0 t first t 0 = t last  t max b f = ∫ v(t) dt (c/2) 2 = r 2  b f 2 N cl = c/(  × sin  N ele = N cl × 1.6  t li  i=1,Nele ;  t ri  i=1,Nele  A li  i=1,Nele ;  A ri  i=1,Nele  P i (cl)  i=1,Nele

6. 6 Cluster Counting Performances (1) bb b from KLOE Transverse spatial resolution In principle, given the time ordered sequence of the drifting clusters, each cluster contributes to the impact parameter with an independent estimate.  b =  bi  √ N cl (saturated by other conributions, like position and sag of sense wire) In reality, multiple electron clusters and single electron diffusion tend to confuse the picture. For N cl = 13 /cm is reasonable to assume:  xy ≈ 50  m F. GrancagnoloILC Workshop Valencia, 8. 11. 2006

7. 7    ≈ 200 mrad Cluster Counting Performances (2) Longitudinal spatial resolution Estimate of dip angle N cl = c/  × 1./sin  For an average c and a minimum ionizing track, N cl = 40 (a few mm extrapolation from one layer to next) extremely powerful tool for 3D track finding! F. GrancagnoloILC Workshop Valencia, 8. 11. 2006 Matching left and right sides gives a very precise measurement of the signals transit time on the wire(limiting factor for time-to-distance conversion) and enhances signal/bkgd. After matching, charge division can be applied to single electrons amplitudes A li and A ri. In principle:  z/L = 0.5% / √N ele Well below 1 mm/m of wire

8. 8 Cluster Counting Performances (3) Transverse momentum resolution Assume:  l = 1.5 m   b = 50  m  B = 1.5 T  n= 20 layers F. GrancagnoloILC Workshop Valencia, 8. 11. 2006 Equal contribution at p  =53 GeV/c, when  p  /p  = 2%, or  p  = 1.2 GeV/c In the end cap one would need the map of B-field and MC calculations. However, resolutions like:  p  /p  = 1.4 × 10 -3 p   1.4 × 10 -2 (end caps) are reachable  p  /p  = 3.0 × 10 -4 p   1.6 × 10 -2 (barrel)

9. 9 Cluster Counting Performances (4) Particle identification It might not be necessary in the  -system. However, for a m.i.p. (a m.i.p. track in the  -system generates approximately 1200 clusters)  (dN cl /dx)/(dN cl /dx) ≈ 3% Example from test beam data:  sepration @ 200 MeV/c G.Cataldi, F.Grancagnolo and S.Spagnolo, INFN-AE-96-07, Mar. 1996, 23p. G.Cataldi, F.Grancagnolo and S.Spagnolo, NIM A386 (1997) 458-469 F. GrancagnoloILC Workshop Valencia, 8. 11. 2006 Equivalent to:  separation ≿  up to 25 GeV/c, ; ≿  up to 55 GeV/c ; ≿  up to 100 GeV/c  separation ~  up to 5 GeV/c (CAVEAT: No data available!, Calculation based on Bethe-Block only!)

10. 10 Cluster Counting Performances (5) beam test measurements p = 200 GeV/c gas mixture = 95%He+5%iC 4 H 10 N cl = 10/cm at  MeV/c experiment:  theory: trunc. mean:    F. GrancagnoloILC Workshop Valencia, 8. 11. 2006

11. 11 Cluster Counting Performances (6) t max  (tmax) ~ 1 ns Drift time of last arriving electron corrected for t.o.f. and for transit time on the wire. Assumed 10 tracks with 100 hits each. From t max one gets t 0 event by event, avoiding long and complicated calibration procedures. Moreover,  (t) ~ 1 ns identifies the trigger of the event F. GrancagnoloILC Workshop Valencia, 8. 11. 2006

12. 12 F. GrancagnoloILC Workshop Valencia, 8. 11. 2006 Drit tube end plug detail

13. 13 F. GrancagnoloILC Workshop Valencia, 8. 11. 2006 × 18 × 36 × 18 Modularity 650 tubes 26 cards 550 tubes 22 cards 1750 tubes 70 cards

14. 14 F. GrancagnoloILC Workshop Valencia, 8. 11. 2006 ×3×3 10500 tubes 420 cards 1/3 barrel

15. 15 F. GrancagnoloILC Workshop Valencia, 8. 11. 2006 1440 tubes 1632 channels 76 cards ×6×6 1/3 end cap

16. 16 F. GrancagnoloILC Workshop Valencia, 8. 11. 2006 ×2×2 End cap

17. 17 F. GrancagnoloILC Workshop Valencia, 8. 11. 2006 Full  -system

18. 18 F. GrancagnoloILC Workshop Valencia, 8. 11. 2006 Channel count Barrel: 31500 tubes 21000 channels 840 cards End caps: 8640 tubes 9792 channels 456 cards Total: 40140 tubes 30792 channels 1296 cards

19. 19 F. GrancagnoloILC Workshop Valencia, 8. 11. 2006  +  − at 3.5 GeV/c

20. 20 F. GrancagnoloILC Workshop Valencia, 8. 11. 2006 50 GeV jet with escaping 

21. 21 F. GrancagnoloILC Workshop Valencia, 8. 11. 2006 80 GeV jet with escaping particles

22. 22 F. GrancagnoloILC Workshop Valencia, 8. 11. 2006 80 GeV jet with escaping particles

23. 23 Cluster Counting 90% He + 10% iC 4 H 10 91% Ar + 5% iCH 4 + 4% N 2 cylindrical tube r = 2 cm at a gain = few × 10 5 time separation (MC) between closest clusters as a function of their distance from the sense wire for different track impact parameters In He In Ar In He, provided that:  rise (and fall) time of single electron signals < 1ns  sampling frequency of electron signals > 2 Gsa/s single electron counting is possible. CAVEAT: Multiple electron clusters (30% in this He mixture) complicates the picture F. GrancagnoloILC Workshop Valencia, 8. 11. 2006

24. 24 Cluster Counting Time separation (MC) between closest ionization clusters along a track as a function of their distance from the sense wire for different track impact parameters In He, provided that:rise (and fall) time of single electron signals < 1ns sampling frequency of electron signals > 2 Gsa/s single electron counting is possible. CAVEAT: Multiple electron clusters (30% in this He mixture) complicates the picture cylindrical tube r = 2 cm gain = few × 10 5 91% Ar + 5% CH 4 + 4% N 2 90% He + 10% i-C 4 H 10 F. GrancagnoloILC Workshop Valencia, 8. 11. 2006