INFN & University of Roma “Tor Vergata” PAMELA SPACE MISSION 20th ECRS Lisbon Piergiorgio Picozza Pamela collaboration INFN & University of Roma “Tor Vergata”

PAMELA Payload for Antimatter Matter Exploration and Light Nuclei Astrophysics Launched in orbit on June 15, 2006, on board of the DK1 satellite by a Soyuz rocket from the Bajkonour launch site. From July 11 Pamela is in continuous data taking mode

PAMELA Collaboration Italy: Russia: Germany: Sweden: Bari Florence Frascati Italy: Trieste Naples Rome CNR, Florence Russia: Moscow St. Petersburg Germany: Siegen Sweden: KTH, Stockholm

WiZard Russian Italian Missions PAMELA

PAMELA Instrument ToF Anticoincidence shield Magnetic spectrometer GF: 21.5 cm2 sr Mass: 470 kg Size: 130x70x70 cm3 Power Budget: 360W ToF MAGNETIC SPECTROMETER B=0.48T Nd-B-Fe 6 planes double sided Si strips 300 m thick Spatial resolution ~3m MDR = 1 TV/c IMAGING CALORIMETER 44 Si layers intervealed with 22 W planes 16.3 X0 / 0.6 l0 e+/p and p/e- at level of 10-4 ~ 10-5 ANTICOINCIDENCE SHIELD Scintillator paddles 10 mm thick Dynamic range of 1÷1000 mip NEUTRON DETECTOR 36 3He counters in polyetilen moderators to discriminate between very high energy electron and proton components SHOWER TAIL CATCHER SCINTILLATOR Neutron Detector Trigger TOF First level trigger Particle identification (up to 1GeV/c) dE/dx Anticoincidence shield Magnetic spectrometer Calorimeter Shower tail catcher Scintillator Neutron Detector

PAMELA capabilities in 3 y. of operation Particle Number (3 yrs) Energy Range Protons 3.108 80 MeV – 700 GeV Antiprotons >3.104 80 MeV – 190 GeV Electrons 6.106 50 MeV – 2 TeV Positrons >3.105 50 MeV – 270 GeV He 4.107 80 MeV/n – 700 GeV/n Be 4.104 C 4.105 Antihelium Limit 5.10-8 80 MeV/n – 30 GeV/n

Resurs-DK1 Spacecraft TsSKB-Progress

Ground Station(s) Main Station: Research Centre for Earth Operative Monitoring “NtsOMZ” (Moscow, Russia); Scheme of PAMELA control room in NTsOMZ Main antenna in NTsOMZ Additional Station: Khanty-Mansisky (Siberia, Russia). Not yet officially established.

Flight data: 2.8 GV electron

Flight data: 1.56 GV positron

Flight data: 4.2 GV electron PAMELA event Flight data: 4.2 GV electron

Flight data: ~500 GV electron

non-interacting proton PAMELA event Flight data: 14.4 GV non-interacting proton

non interacting antiproton Flight data: 15 GV non interacting antiproton

PAMELA event Flight data: 36 GV interacting proton

PAMELA event Flight data: 9.7 GV non-interacting Helium Nucleus

PAMELA event Flight data: 13 GV Interacting Helium Nucleus

Orbit characteristics quasi-polar (70°) elliptical (350÷600 km) 3-years-long mission Orbit characteristics SAA OK

Example: Trigger rate with 3 different trigger configurations

The first three months of Pamela June, 15: Launch June, 15 – July, 11: satellite and instruments commissioning JuLy, 11 – September, 7: -- Satellite commissioning; -- Pamela data taking for 1064 hours for a live time of 733 hours. 12 Caprice 98 balloon flights and about three HEAT balloon flights. Estimation: ~ 210 antiprotons detected, 66 between 10-190 GeV ~ 2200 positrons, 400 between 4.5-50 GeV

The Science of Pamela

Cosmic-ray Antimatter Search PAMELA 2006-2009

Antiproton Measurements

•Background from normal Distortion on the secondary antiproton flux induced by an Extragalactic Antimatter and Black Hole evaporation components Extragalactic Antimatter •Background from normal secondary production Black Hole evaporation •Mass91 data from XXVI ICRC, OG.1.1.21 , 1999 •Caprice94 data from ApJ , 487, 415, 1997 •Caprice98 data from ApJ Letters 534, L177, 2000

Dark Matter What do we espect from Pamela?

NEUTRALINO ANNIHILATION a) CDM neutralinos annihilation in the Galactic halo in minimal SUSY b) In R-parity- violating SUSY

Search of structures in antiproton spectrum Primary production from  annihilation (m() = ~ 1 TeV) ( astro-ph 9904086) Secondary production (upper and lower limits) Simon et al. Secondary production (CAPRICE94-based) Bergström et al.

PAMELA: Cosmic-Ray Antiparticle Measurements: Antiprotons MSSM fd: Clumpiness factors needed to disentangle a neutralino induced component in the antiproton flux A.Lionetto, A.Morselli, V.Zdravkovic JCAP09(2005)010 [astro-ph/0502406]

Distortion of the secondary positron fraction induced by a signal from a heavy neutralino. Baltz & Edsjö Phys.Rev. D59 (1999) astro-ph 9808243

Positron with HEAT

Cosmic-ray antiparticle measurements: positrons Secondary production ‘Moskalenko + Strong model’ (1998) without reacceleration Charge dependent modulation effects Secondary production ‘Leaky box model’ (Protheroe 1982) Primary production from  annihilation (m() = 336 GeV) PAMELA energy range

Primary and Secondary Spectra Unambiguous interpretation of exotic matter signature requires a clear understanding of the secondary spectra and their sources. Primary cosmic ray spectra as a powerful tool for quantify the source of atmospheric neutrino anomaly.

Secondary to Primary ratios

Helium and Hydrogen Isotopes

Protons Helium

High Energy electrons The study of primary electrons is especially important because they give information on the nearest sources of cosmic rays Electrons with energy above 100 MeV rapidly loss their energy due to synchrotron radiation and inverse Compton processes The discovery of primary electrons with energy above 1012 eV will evidence the existence of cosmic ray sources in the nearby interstellar space (r300 pc)

High Energy Radiation Belts – High energy from ~ 1 GeV to ~ 10 GeV – Content of e+, e-, p, 3He – Low L- shell  low altitude – Life time O(seconds)  Secondary production from CR interaction with atmosphere

≈ PAMELA will be able to measure electrons at very high energy to discover sources near the solar system

wizard.roma2.infn.it/pamela Earliest example of the interplay between particles physics and cosmology “We must regard it rather an accident that the Earth and presumably the whole Solar System contains a preponderance of negative electrons and positive protons. It is quite possible that for some of the stars it is the other way about” Dirac Nobel Speech (1933) wizard.roma2.infn.it/pamela The belief that the Universe was baryon symmetric was a mainstream view from the 1930’s into the 1960’s.