AMS the AntiMatter Spectrometer

1
AMSthe Anti-Matter Spectrometer

• The past 10 days on Discovery
• The present 2000
• The future 3 years on the ISS
• STS-91 mission (June 1998)
• ISS 3 year mission (September 2003?)

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AMS in space

• the first large magnetic spectrometer
• i.e.
• the first particle physics experiment
• and
• the biggest silicon system
• in operation to date

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AMSPhysics Goals (1)

• Measurement of H, He, C isotopes
• better understanding of cosmic ray origin and
  propagation in the galaxy
• Antiprotons and positrons
• search for exotic sources
• High energy photons (gt 1 GeV)
• complementary to satellite and ground telescopes

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AMSPhysics Goals (2)
Search for antimatter primary goal of AMS, up to
Z 6

• Antimatter discoveryantistars, primordial
  antimatterExplanation for antimatter domain
  formation?

• No antimatter foundexplanation for antimatter
  disappearance?Strong CP-violation?

Antihelium could originate from primordial
nucleosynthesis OR from antistars anticarbon
could ONLY come from antistars
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Apparatus for the precursor flight AMS-01 (1)

• Construction and test of detector elements
• assembly, integration, system tests
• space qualification  outgassing, vibrations
• Permanent magnet
• 1.2m diameter, 80cm height, 1.9 tons
• 0.15 Tesla
• blocks of Nd-Fe-B of high field strength

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Apparatus for the precursor flight AMS-01 (2)

• Tracker
• 4 inner planes and 2 outer planespartially
  equipped (40)
• 57 modules of 11 to 15 double-sided DC silicon
  microstrip detectors
• front-end Viking/High Dynamic Range4ms peaking
  time, 0.7 mW/ch
• 365W allocated (out of 1 kW), 0.5 Mbit/s (out of
  1), 5MHz ADC on ext. TDR

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Apparatus for the precursor flight AMS-01 (3)

• Time-of-flight - 4 planes
• trigger
• particle velocity and absolute charge
• Anticoincidence - 16 counters
• background rejection (albedo)
• Aerogel Threshold Cherenkov - 2 planes
• 168 10x10cm2 7cm thick solid cells

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The STS-91 Discovery missionJune 2-12, 1998

• Final tests at KSC and installation on the
  Shuttle Discovery
• Launch data download to JSC
• slow rate, high rate
• Landing at KSC back to Europe
• Beam tests ( cosmic muons)
• GSI-Darmstadt Helium, Carbon
• Cern-Geneva charge-1 particles

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Physics from STS-91

• Search for antihelium
• 2,86 million helium nuclei observed
• rigidity 1 to 140 GV
• Search for antimatter
• Cosmic ray proton spectra
• from 0.1 to 200 GeV
• Gamma ray search

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AMS on the International Space Station AMS-02

• design finalisation and optimisation
• space qualification of single elements
• assembly, full space qualification, long term
  operation
• lt2 tons, 2kW, 10g, ?T, (micro)meteorites
• installation on the Space Station (2003)
• 3 to 5 years of data taking
• (if we get He refill)

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Apparatus for ISSAMS-02 (1)

• Superconducting magnet
• Oxford Instruments, 1T (vs. 0.14T)
• Tracker 8 layers, fully equipped
• 192 modules of 7 to 15 double-sided DC silicon
  microstrip detectors, 10?m/30?m resolution
• some 200,000 readout channels
• Synchrotron Radiation Detector (SRD)
• x-rays from high energy electrons in B(E)
• 2400 Crystal/PMT elements, 4800 channels

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Apparatus for ISSAMS-02 (2)

• RICH Aerogel radiator, ??/? ? 10-4
• cosmic ray id. up to 13 GeV per nucleon for A lt
  25, charge id up to Z ? 26
• ECAL 3d sampling calorimeter
• 80 layers of lead and fibers, 15.5 X0
• 0.5 GeV to 1 TeV, proton rej. ? 10-4
• TRD (Transition Radiation Detector)
• 20 layers of radiators and prop. tubes

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so (conclusions)

• Lots of
• work
• we still have to build it !
• physics
• data in 2003 !
• (and fun)!
• HEP physicists (almost) in space (more or less..)
  !