Roberta Sparvoli Roberta Sparvoli for the PAMELA Collaboration University of Rome Tor Vergata and INFN Roma II, Italy Uuuuuu Uuuu uuuuuuu

R. Sparvoli - INFN-SPAZIO/2 - LNF, 16 Febbraio PAMELA scientific program energy range particles/3 years Antiproton flux 80 MeV GeV > Positron flux50 MeV – 270 GeV> Electron flux up to 400 GeV Proton flux up to 700 GeV Electron/positron fluxup to 2 TeV Light Nuclei (up to Z=6) up to 200 GeV/n He/Be/C: /4/5 AntiNuclei search (sensitivity of in He/He)   Unprecedented Statistics and new Energy Range in Cosmic Rays Actual limits: antip&positrons  40 GeV PAMELA is a magnetic spectrometer which will fly on a Russian satellite by Fall Its scientific scope is the measurement of the antiproton and positron spectra up to few hundred GeV, of the proton and electron spectra up to 700 GeV and that of light nuclei.

R. Sparvoli - INFN-SPAZIO/2 - LNF, 16 Febbraio PAMELA detectors Around the main structure detectors are arranged: Shower tail catcher - Scintillator - Neutron Detector Anticoincidenceshield ToF Magnetic spectrometer Calorimeter TRD 3 planes of scintillators S1, S2, S3 Each plane made of 2 crossed layers, segmented in X-Y strips 48 channels  TOF ~ 110ps Used for : TRIGGER: crossing particles TOF: Particle ID and for albedo rejection (upward) dE/dx measurements 1024 straw tubes arranged in 9 detection planes Gas mixture: Xe-CO 2 (80-20%) HV 1400 V; Radiator: 10 planes of Carbon fibre (60 g/l) interleaved to the detection planes Used for : Redundancy in lepton/hadron separation Performance: 5% proton contamination at about 90% electron efficiency Scintillators organized in a TOP paddle and 4 LATeral paddles Detector-efficiency high: >99.9% Used to: help rejection of spurios triggers (used offline in 2nd level trigger) Visit talk dr. Orsi, today aft. Bottom Scintillator Single square scintillator paddle 10 mm thick 6 PMTs Dynamic range of 1÷1000 mip Used for Trigger for ND Neutron Detector 36 proportional counters filled with 3 He, stacked in two planes of 18 counters each, oriented along the y- axis of the instrument. Used for Lepton/hadron separation by n. of neutrons produced in showers Permanent magnet: Made of 5 blocks of Nd-B-Fe Alloy 0.48 T in internal cavity Silicon Tracker: 6 floors of double sided Si- MicroStrip detectors (300  m) X-Strip: 25  m implantation pitch / junction side Y-Strip: 67  m pitch / ohmic side R/O pitch 50  m in X/Y Used to: Impulse reconstruction Charge sign ID 3  m resolution in bending view X 10  m resolution in Y  Max. Ridigity ~ 740 GV 22 planes of Tungsten (2.6mm) interleaved with double sided MacroStrip detectors (2.4 mm pitch along orthogonal directions) 16.3 Rad. Lengths, 0.6 Int. Lengths Total: 4224 channels Used for: Lepton/hadron separation Energy determination >10 4 rejection power for p/e + (and anti-p/e - ) Energy resolution ~ 5 % at 200 GeV Possibility of self-triggering (H.E. electrons – increased GF – used in conjuntion to Shower tail catcher)

R. Sparvoli - INFN-SPAZIO/2 - LNF, 16 Febbraio What is PAMELA now? Flight Model – Munich, Jan 2005

R. Sparvoli - INFN-SPAZIO/2 - LNF, 16 Febbraio Mass&Thermal Model in TsSKB Pressurized Container Mass & Thermal Model PAMELA Mass & Thermal Model was assembled in the clean room of Rome Tor Vergata ( ) and then integrated into the Pressurized Container at TsSKB- Progress (Samara/Russia), between March 2002 and April 2003, for all mechanical compatibility tests. It passed thermal and dynamical qualification tests. Integration in the Container

R. Sparvoli - INFN-SPAZIO/2 - LNF, 16 Febbraio PAMELA Technological Model was assembled and tested (preliminary Acceptance Tests with EGSE: power ON/OFF, telecommands, data transmission through adapter) in the clean room of Rome Tor Vergata in Technological Model It was then shipped to Samara inside a special transport container in April Magnetic compatibility tests and Incoming Tests (stand-alone) already performed. Integration with satellite and transmission to mass memory still in progress (Jan 2005).

R. Sparvoli - INFN-SPAZIO/2 - LNF, 16 Febbraio Flight Model Integration The final Flight Model integration is in progress in Rome clean room since almost 12 months. All flight components have been mounted. From 16/02/2005 a Russian delegation is in Rome for official Acceptance tests of PAMELA FM before delivery to Samara. PAMELA-FM inside Transport Container Design: > 5000 km flight & 1000 km rail, +40/-50°C outside

R. Sparvoli - INFN-SPAZIO/2 - LNF, 16 Febbraio Beam tests SPS, July 2000 SPS, July 2002 Magnet/Tracker, Calorimeter SPS, September 2003 From July 2000 until September 2003 PAMELA Flight Model was extensively exposed to beam tests to study physical performance. Detectors operated at CERN PS/SPS test beams as prototypes and in FM configuration. Final test in Sept

R. Sparvoli - INFN-SPAZIO/2 - LNF, 16 Febbraio Dynamic tests Risposta ricerca di risonanza asse Z per accelerometro MP 14 (montante) PAMELA FM Model passed a cycle of vibration tests at IABG/Munich (January 2005) to verify the final structure. Minimal loads have been imposed to the instrument. 100 channels were mounted. All resonance searches confirm the integrity of the detector after the test.

R. Sparvoli - INFN-SPAZIO/2 - LNF, 16 Febbraio Cosmic ray tracks (Dec. 2004) Since November 2004 PAMELA is set in cosmic-ray acquisition during night shifts.

R. Sparvoli - INFN-SPAZIO/2 - LNF, 16 Febbraio First “physics” results From the statistics acquired by cosmic-ray acquisitions we are analyzing PAMELA performance and comparing with literature.

R. Sparvoli - INFN-SPAZIO/2 - LNF, 16 Febbraio Conclusions – already done (0) Detectors and Systems are designed & ready (1) MASS & THERMAL MODEL  done  A ll tests passed  space qualification! (2) TECHNOLOGICAL MODEL  ~ done  Assembly finished in Rome (~ 1 yr)  Integration with satellite in Samara almost complete (started 05/2004) (3) FLIGHT MODEL  SPS BeamTest of almost complete setup done in Sept for final calibration & alignment  done  Vibration Test (minimal loads) of complete setup for final check of structure – Munich (Jan. 2004)  done

R. Sparvoli - INFN-SPAZIO/2 - LNF, 16 Febbraio Conclusions – to be done The PAMELA launch is in Fall 2005 FLIGHT MODEL  Acceptance tests to be performed (end by 23 Feb. 2005)  Cosmic-ray acquisition (long run) (end by 10 March 2005)  Transport to Samara – Russia (March 2005)  Full integration of PAMELA, ARINA & EOS into satellite (April 2005)  Tests in Samara – Russia (up to 3 months)  All final tests in-situ - Baikonur/Kazahstan (2 – 3 months)