1. 1 Astroparticle Physics with AMS-02 Dr. C.Sbarra INFN-Bologna, Italy On behalf of the AMS collaboration 12th Lomonosov Conference, Moscow 2005

2. 2 Outlook  The AMS experiment and its forthcoming operation on International Space Station (ISS)  The antimatter discovery potential of AMS-02 and the Baryogenesis scenarios investigated  The e +, p, d detection and subsequent impact on the various models of exotic physics Dr.C.Sbarra, INFN-Bologna, Italy 12th Lomonosov Conference, Moscow 2005

3. 3 The Test Experiment: AMS-01 Dr.C.Sbarra, INFN-Bologna, Italy 12th Lomonosov Conference, Moscow 2005 Results: Environmental studies Background studies Fulfill the constraints from space Antimatter/matter limit (<1.1x10 -6 at 95% C.L. PR 366/6, 2002) Onboard the shuttle Discovery (1998)

4. 4 The AMS-02 experiment Dr.C.Sbarra, INFN-Bologna, Italy 12th Lomonosov Conference, Moscow 2005 The knowledge obtained in the precursor 10 days flight AMS-01 (1998) was used to redesign the spectrometer for the ISS:  Long exposure: > 3 years  Superconducting magnet (BL 2 0.86 T,  1m 3 fill volume)  Large acceptance: 0.5 m 2 sr  Many repeated measurements of particle velocity, momentum and charge The Anti Matter Spectrometer

5. 5  Huge statistics of all type of Cosmic rays in the energy range 1 GeV – 1 TeV (/nucl)  For low rates high redundancy and precise detector measurements The AMS-02 experiment PID : The subdetectors

6. 6 The AMS-02 experiment  20 layers of TRD for e + /h sep. (1.5 -300 GeV)  4 layers of TOF for trigger, time (150 ps), β and |Q| meas.  8 layers of double sided Silicon tracker for p (10/30 μm res. b./non b.) and ±Q meas.  VETO Counters  RICH for β (Δβ/β~0.1%) and |Q|  3D sampling ECAL (17X 0 of plastic fibers) for e + e - /h sep. (1.5 GeV-500GeV) Dr.C.Sbarra, INFN-Bologna, Italy 12th Lomonosov Conference, Moscow 2005 PID : The subdetectors Super conducting Solenoid (0.86 T) He vessels

7. 7 The AMS-02 experiment Spectrometer Resolution (P.R. 366/6) Dr.C.Sbarra, INFN-Bologna, Italy 12th Lomonosov Conference, Moscow 2005

8. 8  The physical laws at microscopic level are symmetric between baryons and anti-baryons  The physical Universe seems to be asymmetric (there seems to be only matter) baryogenesis ? - How can evolve an asymmetric universe (totally or even only locally) from a primordial big- bang and with symmetric laws? baryogenesis ? Dr.C.Sbarra, INFN-Bologna, Italy 12th Lomonosov Conference, Moscow 2005 The AMS discovery potential Antimatter in our universe

9. 9 Andrei Shakarov put the necessary conditions for baryogenesis [JETP Lett. 91B,24 (1967)] :  Baryon number B non conservation  C and CP non conservation  Out of equilibrium decay - The inflation is a natural scenario where a baryogenesis can take place: it allows the out of equilibrium condition and it can avoid the a-prori hypothesis of initial symmetric conditions [L.F. Abbott et Al.,Physics Lett.117B(1982)] Antimatter in our universe: Baryogenesis Dr.C.Sbarra, INFN-Bologna, Italy 12th Lomonosov Conference, Moscow 2005

10. 10 Is the Universe globally or only locally asymmetric?  In a totally symmetric universe, high energy CRs could escape from an antimatter domain and get to our galaxy  On the basis of γ-rays observations our matter dominated region has at least the size of cluster of galaxies Is there place for antimatter in a totally asymmetric Universe as seem to be ours? Antimatter in our universe: Baryogenesis Dr.C.Sbarra, INFN-Bologna, Italy 12th Lomonosov Conference, Moscow 2005

11. 11 [M. Y. Khlopov, S.G.Rubin and Al.S.Sakharov hep-ph/0210012 ]  In the matter dominated universe there is also the possibility of small insertions of antimatter regions : Quantum fluctuations of a complex, baryonic charged scalar field caused by inflation can generate antimatter regions that can survive annihilation  There can exist antistar global clusters in our galaxy  The expected signature of such scenario is a flux of 3 He and 4 He accessible to AMS-02 Antimatter in our universe: Baryogenesis Dr.C.Sbarra, INFN-Bologna, Italy 12th Lomonosov Conference, Moscow 2005

12. 12 An anti-nucleus can be found in Cosmic Rays, with a spectrometer on top of the atmosphere (balloons) or on a satellite (Pamela, AMS-02) Antimatter in our universe: Experimental searches Pamela Dr.C.Sbarra, INFN-Bologna, Italy 12th Lomonosov Conference, Moscow 2005

13. 13 Antimatter in our universe: Antinuclei, antiparticles  The antiparticles are “secondaries” produced by CR interactions with ISM through inelastic collisions – “spallation” Flux 4 He O(10 -12 ), D O(10 -8 ), p O(10 -4 ), e+ O(10 -3 )  But some antiparticles can be “primaries” from exotic sources of antimatter or DM annihilation (an He would be evidence of antistars) Dr.C.Sbarra, INFN-Bologna, Italy 12th Lomonosov Conference, Moscow 2005

14. 14  Ratio e + /(e + +e - ) can reveal neutralino annihilations [Phys.Rev.D 65/6] HEAT data show possible excess around ~ 10GeV Antimatter in our universe: antiparticles - Positrons Edsjö et al Dr.C.Sbarra, INFN-Bologna, Italy 12th Lomonosov Conference, Moscow 2005

15. 15  10 6 AMS can measure  10 6 positrons up to 300 GeV and can confirm or not the bump  Flux ratio : p/e+ ~ 10 3 Strong p/e+ rejection Strong p/e+ rejection TRD : Rej~10 3 /10 2 in 3-300 GeV - TRD : Rej~10 3 /10 2 in 3-300 GeV ECAL: Rej ~ 10 4 for E ~ 500 GeV - ECAL: Rej ~ 10 4 for E ~ 500 GeV (TRD + ECAL together Rej ≥ 10 5 ) (TRD + ECAL together Rej ≥ 10 5 ) Antimatter in our universe: antiparticles - Positrons Dr.C.Sbarra, INFN-Bologna, Italy 12th Lomonosov Conference, Moscow 2005

16. 16  Antideuteron is to be observed in CRs D limit from Bess < 1.9x10 -4 (m 2 ·s·sr·GeV/n) [28th ICRC 2003] The neutralino (the lightest supersymmetric particle) would be left as relic by large amount of sparticles decayed  AMS-02 can observe O(10) low momentum D from neutralino annihilation [F.Donato et Al.1999] Antimatter in our universe: Antideuterons Dr.C.Sbarra, INFN-Bologna, Italy 12th Lomonosov Conference, Moscow 2005

17. 17  The known ratio of D/p is ~ 10 -5 in the observed universe  AMS-02 can detect D from antimatter domains : D/p ~ 10 -5 (AMS-01 observed ~ 100 p, thus D was unobservable) The ratio of primordial He to D is ~ 10 4 and in CR it is about 10 thus any D from antimatter domain would be accompaigned by He or p Antimatter in our universe: Antideuterons Dr.C.Sbarra, INFN-Bologna, Italy 12th Lomonosov Conference, Moscow 2005

18. 18  Antiproton flux O(10 -4 ) at E~1 GeV (e - /p ~ 10 3 at E ~ 1 GeV strong e - /p rejection at this energy)  Antiprotons in CRs have been detected up to O(10 GeV) and all seem to be compatible with secondary production Antimatter in our universe: Antiprotons Dr.C.Sbarra, INFN-Bologna, Italy 12th Lomonosov Conference, Moscow 2005

19. 19 Antimatter in our universe: Antiprotons Dr.C.Sbarra, INFN-Bologna, Italy 12th Lomonosov Conference, Moscow 2005  Simulation of three years of high statistics measurements of antiproton spectrum  AMS-02 will be able to detect antiprotons up to 400GeV [V.Choutko,Nucl.Phys.B Proc.Suppl.113-2002]

20. 20  Proton rejection: good control of charge confusion, interaction with the detector and misreconstructed tracks  Electron rejection: use TOF + RICH beta measurements at low energies, TRD and ECAL rejection capability at high energy Antimatter in our universe: Antiprotons Dr.C.Sbarra, INFN-Bologna, Italy 12th Lomonosov Conference, Moscow 2005

21. 21 Wolfendale & Stecker hypothesis [19 th ICRC proc. p.354]:  We know that the mean lifetime of a CR in the galaxy falls with energy as E -δ with δ~0.7  If antiprotons are produced and accelerated in an antimatter domain as the protons are in our galaxy  The antiproton/proton ratio, at high energies, would go ~ E δ with δ ~ 0.7, the antiprotons being mainly extragalactic and the protons galactic Antimatter in our universe: Antiprotons Dr.C.Sbarra, INFN-Bologna, Italy 12th Lomonosov Conference, Moscow 2005

22. 22  Primary hypothesis: p/p  E 0.7 From Stecker & Wolfendale, 19th ICRC (La Jolla) 1985, OG6.1-8, p354  At energy E>100GeV the experimental data could discriminate between primary and secondary hypothesis Dr.C.Sbarra, INFN-Bologna, Italy 12th Lomonosov Conference, Moscow 2005 Antimatter in our universe: Antiprotons [data from Golden, Buffington, Bogolmolov]

23. 23  Most recent data on p/p [by Picozza and Morselli J.Phys.G: Nucl.Part.Phys.29 (2003)]  Superimposed extragalactic hypothesis, black hole evaporation model, secondary production  More data could discriminate between the various models for E >10GeV Dr.C.Sbarra, INFN-Bologna, Italy 12th Lomonosov Conference, Moscow 2005 Antimatter in our universe: Antiprotons AMS-01 [V.Choutko]

24. 24  As other antiparticles, antiprotons at lower energy could reveal neutralino annihilation:  χχ WW,.. e+, p, D, γ… ( Indirect search in several channels )  Flux of products depends on neutralino density, CRs propagation terms,.. Antimatter in our universe: Antiprotons Dr.C.Sbarra, INFN-Bologna, Italy 12th Lomonosov Conference, Moscow 2005

25. 25 Antimatter in our universe: Antiprotons Signal : 1) M  =964 GeV (  4200) 2) M  =777 GeV (  1200) Dr.C.Sbarra, INFN-Bologna, Italy 12th Lomonosov Conference, Moscow 2005 Ullio (1999)  Antiprotons are particularly sensitive to the physics details of CR propagation (controlled by B/C ratio), particularly at low momentum

26. 26  The AMS-02 spectrometer will measure CRs fluxes with high precision for more than three years  AMS-02 will be sensitive to antinuclei up to 100 Mpc of distance  AMS-02 can discriminate between a totally symmetric or an antisymmetric universe also through antiprotons at E >100GeV  AMS-02 will have the sensitivity to detect the products of DM annihilation in our galaxy through positrons, antideuterons and antiprotons at O(GeV) energy Conclusion Dr.C.Sbarra, INFN-Bologna, Italy 12th Lomonosov Conference, Moscow 2005

27. 27 SLIDES EXTRA

28. 28 The AMS-02 experiment  Thermal range (day/night ΔT ~100 0 )  Vibration (6.8 G RMS) and G-Forces (17 G, 9 G take off)  Weight limitation (7000 kg)  Power limitation (2000 W)  Vacuum: < 10 -10 Torr  Radiation ionizing flux ~1000 cm -2 s -1  Orbital debris and micrometeorites (Redunduncy)  Must operate without human intervention (Redunduncy) Dr.C.Sbarra, INFN-Bologna, Italy 12th Lomonosov Conference, Moscow 2005 Operation in Space constraints

29. 29

30. 30 p/pbar all recent + Ams01 AMS-01

31. 31 p/pbar – all recent data

32. 32 Energy resolution (from Palomares)  (E)/E ~ 3% for 100 GeV electrons

33. 33 The AMS-02 experiment AMS –γ : 2 modes detection Converted  : Detection of the e+e- pair in the tracker Calorimeter : Standalone trigger

34. 34 The AMS-02 experiment Energy Resolution ….

35. 35 The AMS-02 experiment Angular Resolution (tracker)