AMS2: Alpha Magnetic Spectrometer

Collaboration:

- Italy: INFN Bologna, Milano, Perugia, Pisa, Roma I, Siena, Trieste (Italy); Agenzia Spaziale Italiana
- China: Accademia Sinica, CALT, IEE, Shandong Univ.
- Finlandia: HUT, Turku Univ.
- France: ISN, LAPP
- Germany: RWTH I e III, MEPI
- Russia: ITEP, LIP, MEPI, SRI-RAS
- Spain: CIEMAT
- Switzerland: ETH, Geneva Univ.
- USA: Boston Univ., CALTECH, J.Hopkins Univ., MIT, Maryland Univ.

Location of the experiment:Shuttle and International Space Station

National Responsible: R. Battiston (Pg)

1. Goal of the experiment

The disappearance of the antimatter and the presence at all scales in our universe of non-luminous components of matter (dark matter) are the two most intriguing mysteries in our current understanding of the structure of the Universe. To study these problems by measuring with the highest accuracy the composition of Cosmic Rays, a high energy physics experiment, the Alpha Magnetic Spectrometer (AMS) is scheduled for installation on the International Space Station for a three year mission. In preparation for this long duration mission AMS flew a ten days precursor mission on board of the space shuttle Discovery during flight STS-91 in June 1998.

More on the experiment…

2.

Activities during 2001

During this year the construction of the sub-detectors for AMS2 has advanced significantly. A completed ECAL module has been constructed to undergo Space Qualification tests. The silicon ladders production has started in all three production centres, and very good results have been obtained from the industrial production line. Various elements of the RICH and ToF subsystems have been developed as well. Several papers have been published both and journals and conference proceedings. A large effort has been performed to develop the thermal system for the entire AMS experiment as well as for the various subsystems.

The following achievements have been obtained:

Completion full size ECAL prototype | 30-09-2001 | 80%
Development of FE VLSI and of the FE/DAQ ECAL board | 31-12-2001 | 60%
Development of WEB browsing for sub-ntuple development of sub-ntuples on demand software | 30-09-2001 | 50%
Development of a reconstruction and particle tracking program for AMS | 30-12-2001 | 60%
HV ECAL prototype development board | 30-11-2001 | 100%
Completion ordering AMS-02 silicon sensors | 30-12-2001 | 50%
Final prototype for ToF HV | 31-07-2001 | 80%
Completion of 100 Silicon Ladders for the AMS Si Tracker | 30-12-2001 | 70%
Delivery of 40+35 km of superconducting cable for the AMS magnet construction | 30-03-2001 | 100%

Milestones 2002:

Completion of ECAL Space Qualification Tests | 30-04-2002
Completion of ECAL test beam data analysis | 30-06-2002
Start flight modules production (HV, LV, EDR) for ECAL | 30-09-2002
Completion HV divider + FEE ECAL | 30-11-2002
Completion of 192 tracker Silicon Ladders | 30-11-2002
Production of 70% of the silicon sensors for the Silicon Tracker | 30-11-2002
Development of tracker power supplies engineering models | 30-11-2002
Proposal for organization and distribution of AMS-02 data | 30-11-2002

3. INFN contribution to the experiment in terms of manpower and financial support:

Manpower: 66 researchers (40.5 FTE), 15 technicians (4.5 FTE)

Budget for the year 2002: 2512 kEuro

4. Publications in refereed journals (in 2001): 1

5. Conference talks (in 2001): 14

6. Number of undergraduate and doctoral thesis on the experiment:

13 (INFN only)

7. Leadership roles and primary responsibilities in the experiment:

Coordination of the Silicon Tracker, Coordination of the Electromagnetic Calorimeter, Coordination of the Time of Flight system, Coordination of the Ring Imaging Cherenkov Detector, Co-chairmanship of the AMS Astrophysics Board, Chairman of AMS-Gamma Working group

8. Innovative instruments

Space qualitification of a several large, state of the art, particle detectors, including: Superconducting magnet, based on a very thin superconducting cable developed by a INFN-ETHZ Collaboration (LASA-Milano). Very large double sided Silicon Tracker (6 m^2), 1 cubic meter, 10 um resolution in the bending plane. Solid state RICH detector based on high density multichannel photomultipliers. High accuracy Time of Flight (120 ps). Low power space qualified electronics. Qualified onboard software

9. Competing experiments

Pamela on the Russian Arktica in 2003-4 however with ~200 times smaller detector acceptance and 4 times lower maximum detectable rigidity.

10. International Committee which has reviewed the experiment

The AMS Experiment has been examined and approved by several international Committees among which:

- DoE referee Committee in April 1995 for the Shuttle Mission and in 1998 for AMS on the ISS
- INFN referee Committee in 1995, Russian Academy of Sciences in 1995.
- During 1995-96 various referees Committees have approved the participation to the AMS experiment in various countries/institutes: ETHZ, Swiss National Found, IN2P3, DARA, CIEMAT, TEKES.

AMS2 is annually reviewed by the INFN National Committee II