1. Davide Vitè - MInstPhys CPhys Particle Physics 2000, Edimburgh, 12 April 2000 1 AMS the Anti-Matter Spectrometer n The past:10 days on Discovery n The present:2000 n The future:3 years on the ISS n STS-91 mission (June 1998) n ISS 3 year mission (September 2003?)

2. Davide Vitè - MInstPhys CPhys Particle Physics 2000, Edimburgh, 12 April 2000 2 AMS in space AMS in space the first large magnetic spectrometer i.e. the first particle physics experiment and the biggest silicon system in operation to date

3. Davide Vitè - MInstPhys CPhys Particle Physics 2000, Edimburgh, 12 April 2000 3 AMS Physics Goals (1) n Measurement of H, He,… C isotopes –better understanding of cosmic ray origin and propagation in the galaxy n Antiprotons and positrons –search for exotic sources n High energy photons (> 1 GeV) –complementary to satellite and ground telescopes

4. Davide Vitè - MInstPhys CPhys Particle Physics 2000, Edimburgh, 12 April 2000 4 n Antimatter discovery: antistars, primordial antimatter Explanation for antimatter domain formation? AMS Physics Goals (2) n No antimatter found: explanation for antimatter disappearance? Strong CP-violation? Antihelium could originate from primordial nucleosynthesis OR from antistars anticarbon could ONLY come from antistars Search for antimatter: primary goal of AMS, up to |Z| = 6

5. Davide Vitè - MInstPhys CPhys Particle Physics 2000, Edimburgh, 12 April 2000 5 Apparatus for the precursor flight: AMS-01 (1) n Construction and test of detector elements –assembly, integration, system tests –space qualification : outgassing, vibrations n Permanent magnet –1.2m diameter, 80cm height, 1.9 tons –0.15 Tesla –blocks of Nd-Fe-B of high field strength

6. Davide Vitè - MInstPhys CPhys Particle Physics 2000, Edimburgh, 12 April 2000 6 Apparatus for the precursor flight: AMS-01 (2) n Tracker –4 inner planes and 2 outer planes partially equipped (~40%) –57 modules of 11 to 15 double-sided DC silicon microstrip detectors –front-end Viking/High Dynamic Range 4  s peaking time, 0.7 mW/ch –365W allocated (out of 1 kW), 0.5 Mbit/s (out of 1), 5MHz ADC on ext. TDR

7. Davide Vitè - MInstPhys CPhys Particle Physics 2000, Edimburgh, 12 April 2000 7 Apparatus for the precursor flight: AMS-01 (3) Apparatus for the precursor flight: AMS-01 (3) n Time-of-flight - 4 planes –trigger –particle velocity and absolute charge n Anticoincidence - 16 counters –background rejection (albedo) n Aerogel Threshold Cherenkov - 2 planes –168 10x10cm 2 7cm thick solid cells

8. Davide Vitè - MInstPhys CPhys Particle Physics 2000, Edimburgh, 12 April 2000 8 The STS-91 Discovery mission June 2-12, 1998 n Final tests at KSC and installation on the Shuttle Discovery n Launch: data download to JSC –slow rate, high rate n Landing at KSC: back to Europe n Beam tests (+ cosmic muons) –GSI-Darmstadt: Helium, Carbon –Cern-Geneva: charge-1 particles

9. Davide Vitè - MInstPhys CPhys Particle Physics 2000, Edimburgh, 12 April 2000 9 Physics from STS-91 n Search for antihelium –2,86 million helium nuclei observed –rigidity: 1 to 140 GV n Search for antimatter n Cosmic ray proton spectra –from 0.1 to 200 GeV n Gamma ray search

10. Davide Vitè - MInstPhys CPhys Particle Physics 2000, Edimburgh, 12 April 2000 10 AMS on the International Space Station: AMS-02 n design finalisation and optimisation –space qualification of single elements n assembly, full space qualification, long term operation –<2 tons, 2kW, 10g,  T, (micro)meteorites n installation on the Space Station (2003) –3 to 5 years of data taking n (if we get He refill…)

11. Davide Vitè - MInstPhys CPhys Particle Physics 2000, Edimburgh, 12 April 2000 11 Apparatus for ISS: AMS-02 (1) n Superconducting magnet – –Oxford Instruments, 1T (vs. 0.14T) n Tracker: 8 layers, fully equipped n 192 modules of 7 to 15 double-sided DC silicon microstrip detectors, 10  m/30  m resolution n some 200,000 readout channels n Synchrotron Radiation Detector (SRD) –x-rays from high energy electrons in B(E) –2400 Crystal/PMT elements, 4800 channels

12. Davide Vitè - MInstPhys CPhys Particle Physics 2000, Edimburgh, 12 April 2000 12 Apparatus for ISS: AMS-02 (2) n RICH: Aerogel radiator,  /   10 -4 –cosmic ray id. up to 13 GeV per nucleon for A < 25, charge id up to Z  26 n ECAL: 3d sampling calorimeter –80 layers of lead and fibers, 15.5 X 0 –0.5 GeV to 1 TeV, proton rej.  10 -4 n TRD (Transition Radiation Detector) –20 layers of radiators and prop. tubes

13. Davide Vitè - MInstPhys CPhys Particle Physics 2000, Edimburgh, 12 April 2000 13 so…… (conclusions) n Lots of –work n we still have to build it ! –physics n data in 2003 ! –(and fun)! n HEP physicists (almost) in space (more or less..) !