PAMELA SPACE MISSION ICHEP 2006 MOSCOW Piergiorgio Picozza Pamela collaboration INFN & University of Roma “Tor Vergata”

PAMELA Payload for Antimatter Matter Exploration and Light Nuclei Astrophysics 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

BariFlorenceFrascati Italy: TriesteNaplesRome CNR, Florence Moscow St. Petersburg Russia: India: Mumbay Germany: Siegen Sweden: KTH, Stockholm PAMELA Collaboration

WiZard Russian Italian Missions WiZard Russian Italian Missions PAMELA

Pamela Flight Model Anticoincidence Shield TOF First level trigger Particle identification (up to 1GeV/c) dE/dx MAGNETIC SPECTROMETER B=0.48T 6 planes double sided Si strips 300  m thick Spatial resolution ~3  m MDR ~ 1400GV/c Shower Tail Catcher Scintillator NEUTRON DETECTOR 36 3 He counters in polyetilen moderators to discriminate between very high energy electron and proton components GF: 21.5 cm 2 sr Mass: 470 kg Size: 130x70x70 cm 3 Power Budget: 360W IMAGING CALORIMETER : 44 Si layers intervealed with 22 W planes 16.3 X 0 / 0.6 l 0 e+/p and at level of ~ 10 -5

On-ground muon results 2005  acquisition of atmospheric particles during PAMELA test before delivering  Check of spectrometer systematics with positive and negative muons Preliminary results: - - no efficiency correction - - first-order alignment - - no ETA p.f.a. Preliminary!

Particle Number (3 yrs) Energy Range Protons MeV – 700 GeV Antiprotons > MeV – 190 GeV Electrons MeV – 2 TeV Positrons > MeV – 270 GeV He MeV/n – 700 GeV/n Be MeV/n – 700 GeV/n C MeV/n – 700 GeV/n Antihelium Limit MeV/n – 30 GeV/n PAMELA capabilities in 3 y. of operation

Resurs-DK1 Spacecraft TsSKB-Progress

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

Flight data: 2.8 GV electron

PAMELA event Flight data: 4.2 GV electron

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

PAMELA event Flight data: 13 GV Interacting Helium Nucleus

PAMELA event Flight data: 14.4 GV non-interacting proton

PAMELA event Flight data: 36 GV interacting proton

Flight data: ~500 GV/c electron

e-e- e+e+ p Topological development of the shower variable versus rigidity [GV] e-e-e-e- e+e+e+e+ p p

e-e- e+e+ p He dE/dx in the calorimeter versus rigidity [GV] R dE/dx

Orbit characteristics quasi-polar (70°) elliptical (300÷600 km) 3-years-long mission SAA

Passage in South Atlantic Anomaly Neutron counts

Trigger Rate Example: Trigger rate with 3 different trigger configurations

The Science of Pamela

Cosmic-ray Antimatter Search PAMELA

Antiproton Measurements

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

Dark Matter What do we espect from Pamela?

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

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

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

cMSSM see Aldo Morselli talk

cMSSM A 0 = 0,  > 0, m t =174 GeV see Aldo Morselli talk

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

Positron with HEAT

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

Concomitant Goals  Near electrons sources  Solar Flare Particle Spectra  Charge-Sign Dependent Solar Modulation  New Radiation Belts

High Energy electrons 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 eV will evidence the existence of cosmic ray sources in the nearby interstellar space (r  300 pc)

Charge-Sign Dependent Solar Modulation  Osservational evidence that the negative charge component of galactic cosmic rays is modulated in the heliosphere differently than the positive one.  Modification and modulation of Galactic Cosmic Ray spectra in the heliosphere complicate the interpretation of the exotic matter results at low energy. Measurements of the abundances of species with the same mass but different charge sign in A + and A - of the solar cycle.

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

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

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) Dirac Nobel Speech (1933)  wizard.roma2.infn.it/pamela