1. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 1 THE CHERENKOV IMAGER of the AMS02 EXPERIMENT The AMS RICH collaboration: Bologna, Grenoble, Lisbon, Madrid, Maryland, Mexico M. Buénerd LPSC Grenoble AMS

2. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 2 PLAN  The AMS02 spectrometer  Physics program  The Cherenkov imager  In-beam test results

3. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 3 Capabilities of the spectrometer  Measure particle energy from ~ 0.4 GeV/n up to ~ 1 TeV/n  Discriminate lepton-hadron  HE  ray measurement  Identify ions or elements over the largest possible energy range

4. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 4 AMS Scientific Program on the ISS High statistics study of the Cosmic Ray particles flux: Allowing sensitive search for : Primordial antimatter (primary goal of the project) : Dark matter (neutralino annihilation) : High energy gamma ray astronomy

5. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 5 Main purpose: The only AMS detector dedicated to Isotope identification (A & Z) Also (redundant) : p/e - and p/e + discrimination Albedo particle rejection _ The AMS Cherenkov imager

6. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 6 The isotopic abundance ratio 10 Be/ 9 Be depends on: - Time of confinement of CRs in galaxy - ISM density and galactic halo size 6 weeks counting è ~ 200000 events ! A.Bouchet et al,Nucl.Phys A668(2000) 7 Be 9 Be 10 Be Simulation of 10 Be detection isomax

7. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 7 The RICH inside AMS ECAL Photodetector plane (680 PMTs) Radiator(s) Conical mirror AMS spectrometer NaF aerogel Cherenkov Radiator Photo- detectors

8. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 8 Sodium Fluoride NaF, n = 1.33 thickness 5 mm Aerogel n = 1.05 thickness 30 mm Radiator plane P range ~ 3-10GeV/c/n P range ~ 1-4 GeV/c/n

9. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 9 4x4 Light Guides 7.5x7.5mm 2 PMT Hamamatsu R7900_M16 4x4 pixels (4.5x4.5mm 2 ) Front End Electronics: Charge preamplifier Track&hold +MPX 16 chan (x2gains) ADC High voltage divider Magnetic Shielding profile (Stray field up to 300G) Photodetector cell

10. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 10 ½ module of final detector 96 PMTs (1536 pixels) Light Guides FE+DAQ Radiators: AGL 1.03 < n < 1.05 NaF n=1.33 (CR only) The RICH prototype

11. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 11 with HE ion beam at CERN Tests of the AMS RICH prototype Beam production principle* Measurements Results * M. Buénerd and I. Efthymiopoulos, CERN report AB-2003-052

12. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 12 Multi-ion beam production Incident SPS - Pb ion beam (20GeV/c/n) - In ion beam (158GeV/c/n) Production target Momentum analysis BB B  Cte x  A/Z Beam fragmentation è B  Cte x  beam A/Z Example:  A/Z=2 è D, He, Li, Be, B, C,…, Si,.., Ca,…, 52 Fe,.. and beyond, but…. Testing detector Few mrad 500m beam line

13. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 13 Intensity of ion beam fragments vs Cosmic Ray flux Cosmic Ray flux J.A. Simpson ARNS 33(1983)323 Beam fragments (A/Z=2) (From dE/dX scintillator ) Similarity of the 2 spectra  controllable CR equivalent flux ~Nuclear charge Z

14. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 14 2 Runs October 2002: 20 GeV/nucleon 208 Pb  fragments A<~60 (z~30) 5 million events collected October 2003 : 158 GeV/nucleon 115 Cd  fragments A<115 (z=49) 11 million events collected

15. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 15 Experimental setup Prototype & RO electronics MWPC dE/dX Scintillators or Cherenkov

16. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 16 Close-up view of matrix with mirror

17. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 17 20GeV/n Cherenkov rings Z 2 3 6 >~16 >16 He Li C Si-P ? ~Fe ?

18. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 18 Velocity reconstruction 2002  spectra fitting Ring fitting Z=1 particles Z=1 particles Aerogel CIEMAT Madrid analysis

19. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 19  (Z) resolution 2002 N γ in the ring ~ Z 2 Limit set by pixel size Aerogel 1.03 CIEMAT Madrid analysis

20. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 20 Charge resolution 2002  (Z) < ~.2 up to Z=26 (n=1.05) Combining RICH+TRCKR Courtesy M.Pohl, Ge n eva U. Courtesy M. Pohl et al. Individual Element separation 

21. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 21 2003 comparison of Aerogels H (Nominal = 44 cm) Test beam 2003 RESULTS (H = 33,5 cm) TYPESIZE (Z=1,  = 1)(Z=2,  = 1) PH. YIELD  MAT 1.033 x 1 cm11,0 ± 0.136,0 ± 0.1(0.487 ± 0.006) x 10 -3 NOV 1.031 x 3 cm10,6 ± 0.134,7 ± 0.1(0.468 ± 0.005) x 10 -3 NOV 1.051 x 2.5 cm14,6 ± 0.347,6 ± 0.1(0.484 ± 0.007) x 10 -3 Specific runs to compare the performances for radiators with different refraction index H = 33.5 cm (full contained rings) ELECTED

22. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 22 Cells integration April 2004

23. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 23 coating (Spares from the prototype used) Finally: 680 PMT cells ASSEMBLED POTTED COATED TESTED SORTED 9 failures ( 3 due to PMT failure) Ready for final counter integation

24. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 24 Summary The study of the AMS RICH prototype with 20 & 158 GeV/n ions has allowed to: 1.Perform an end-to-end test of the instrument with a broad range of nuclear charges (1<Z<~49). 2.Measure the performances of the prototype: Velocity resolution :  /  = 0.7 10 -3 for Z=1 particles Charge resolution :  (Z) ~30 3. All the RICH prototype elements have been thoroughly tested (PMT cells, FE+RO electronics, reconstruction algorithms) and validated. The final counter integration has started (end Nov 05).

25. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 25 AMS is an International Collaboration NASA provides: Three shuttle flights and Mission Management at JSC (S. Porter - Project Manager) USA A&M FLORIDA UNIV. JOHNS HOPKINS UNIV. MIT - CAMBRIDGE NASA GODDARD SPACE FLIGHT CENTER NASA JOHNSON SPACE CENTER UNIV. OF MARYLAND-DEPRT OF PHYSICS UNIV. OF MARYLAND-E.W.S. S.CENTER YALE UNIV. - NEW HAVEN MEXICO UNAM DENMARK UNIV. OF AARHUS FINLAND HELSINKI UNIV. UNIV. OF TURKU FRANCE GAM MONTPELLIER LAPP ANNECY LPSC GRENOBLE GERMANY RWTH-I RWTH-III MAX-PLANK INST. UNIV. OF KARLSRUHE ITALY ASI CARSO TRIESTE IROE FLORENCE INFN & UNIV. OF BOLOGNA INFN & UNIV. OF MILANO INFN & UNIV. OF PERUGIA INFN & UNIV. OF PISA INFN & UNIV. OF ROMA INFN & UNIV. OF SIENA NETHERLANDS ESA-ESTEC NIKHEF NLR PORTUGAL LAB. OF INSTRUM. LISBON ROMANIA ISS UNIV. OF BUCHAREST RUSSIA I.K.I. ITEP KURCHATOV INST. MOSCOW STATE UNIV. SPAIN CIEMAT - MADRID I.A.C. CANARIAS. SWITZERLAND ETH-ZURICH UNIV. OF GENEVA CHINA BISEE (Beijing) IEE (Beijing) IHEP (Beijing) SJTU (Shanghai) SEU (Nanjing) SYSU (Guangzhou) SDU (Jinan) ACAD. SINICA (Taiwan) CSIST (Taiwan) NCU (Chung Li) NCKU (Tainan) NCTU (Hsinchu) NSPO (Hsinchu) KOREA EWHA KYUNGPOOK NAT.UNIV. 50 universities, 500 participants

26. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 26 TOF Hodoscopes (TOF & dE/dX) Cryostat & SC Magnet (B = 1T) Tracker (P & dE/dX measurement) EMC (ID em particles) RICH (particle & isotope ID A<~16 ?, Z<~25) TRD e + /p & e - /p Discrim P<300GeV/c - VETO skirt THE AMS2 SPECTROMETER

27. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 27 2x Dipole Coils 2x6 Racetrack Coils 2,500 l Superfluid He SC magnet in support structure

28. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 28 What for ? Which imaging technique ? What radiator(s) ? What photodetectors ? What performances ?  Prototype and test results The Cherenkov Imager

29. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 29 Largely dictated by constraints on: - Volume available (Shuttle cargo bay) - Weight (currently ~190kg) - Power consumption (currently ~150W) - Long term reliability of components - Magnetic field in the photodetector region - Isotropic flux (No point source like in accelerators) Proximity focusing counter, photomultipliers 2 radiators for a maximum momentum range for isotope identification (~1-10 GeV/c/nucleon) è Which imaging technique ?

30. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 30 AEROGEL radiator plane. Produced in Japan or Russia, Characterized at UNAM Mexico Support structure made by CIEMAT Madrid Structure Assembly (Bologna/Gavazzi) LOWER PANEL Photodetector plane 680 PMTs ~10 4 pixels of photosensors (Japan) Photon drift space Mirror made in USA (~ 13kg) Resp. Bologna Mech. Design by Gavazzi Space, Italy NaF radiator Rich assembly (exploded view)

31. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 31 Selection of the ion sample Z=2 He Z=82 Pb beam Z=8 O Z=20 Ca Z=50 Zr N Z Selection line (A/Z=Cte) Changing the magnetic field in the beam line changes the ion mass/charge sampled Chart of the nuclides

32. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 32 The CERN H8 beam line Production target Position (m) RICH Momentum Analysis Dispersion dipole Analysis Dipole Acceptance collimators Image collimators 0 -480-420 -464 -352 -150 -80 TOF1 -26 NA45 Wall / Experimental area Tracker TOF CREAM  P/P~1% TOF2

33. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 33 Front end electronics Principle: Spectroscopy type charge preamplifier, 16 multiplexed channels, 2 gain (x1 & x5) modes

34. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 34  To be cross checked with calibration from the ion charge distribution 3 pixels PMT linearity measurement

35. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 35 Team (night shift) at work

36. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 36 M.Marton Module coating Coating Aug 2004

37. Nov 30-Dec 5, 2004RICH2004 Int. Workshop, Playa Del Carmen, MexicoM. Buénerd 37 Surface scattering