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

4 F. GrancagnoloILC Workshop Valencia,  -System basic element: drift tube radius 2.3 cm filled with 90% He – 10% iC 4 H 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 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, 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 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,

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, 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 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, 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 × p   1.4 × (end caps) are reachable  p  /p  = 3.0 × p   1.6 × (barrel)

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:  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) F. GrancagnoloILC Workshop Valencia, 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 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,

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,

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

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

14 F. GrancagnoloILC Workshop Valencia, ×3× tubes 420 cards 1/3 barrel

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

16 F. GrancagnoloILC Workshop Valencia, ×2×2 End cap

17 F. GrancagnoloILC Workshop Valencia, Full  -system

18 F. GrancagnoloILC Workshop Valencia, Channel count Barrel: tubes channels 840 cards End caps: 8640 tubes 9792 channels 456 cards Total: tubes channels 1296 cards

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

20 F. GrancagnoloILC Workshop Valencia, GeV jet with escaping 

21 F. GrancagnoloILC Workshop Valencia, GeV jet with escaping particles

22 F. GrancagnoloILC Workshop Valencia, GeV jet with escaping particles

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,

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 × % Ar + 5% CH 4 + 4% N 2 90% He + 10% i-C 4 H 10 F. GrancagnoloILC Workshop Valencia,