Search for Antiparticles in Cosmic Rays in Space and the Earth s Atmosphere Philip von Doetinchem I. Phys. Inst. B, RWTH Aachen University Hausseminar, Aachen 6th of June 008
Overview cosmic ray physics in the GeV-TeV range the AMS-0 detector for the ISS in Space: anticoincidence counter qualification of hardware integration analysis prospects for AMS-0 the PEBS detector in Earth s atmosphere: properties of Earth s atmosphere and magnetic field simulation of cosmic ray measurements at the Southpole prospects for PEBS Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p.
Particle & Astro Physics particle physics & astrophysics are merging WMAP 5 years use particle physics methods in astrophysics and get input to particle physics from astrophysics important observations cry for explanations: Dark matter exists! What is the nature? Supersymmetry, Kaluza- Klein, Where does the asymmetry between matter and antimatter in the universe come from? Search for Antiparticles in Cosmic Rays Ph. von Doetinchem Hausseminar 08/06/06 p. 3
Cosmic Rays AMS-0 PEBS sr - s - m - - GeV Flux 4 3 - - -3-4 -5 solar Modulation: Φ = 44.64 MV AMS-0 protons AMS-0 helium AMS-0 electrons HEAT 94/5 positrons AMS-0 positrons EGRET photons IMAX antiprotons Caprice 94 antiprotons Caprice 98 antiprotons BESS 95/97 antiprotons BESS 0 antiprotons proton helium electron positron photon antiproton - kinetic Energy [GeV] learn about sources, acceleration, propagation, age, grammage of matter, halo size, good agreement of models in the GeV-TeV range for particles, some unexplained features in antiparticle/photon spectra galdef 59978 / 59998(α) Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 4
Positrons & Antiprotons no primary sources for positrons and antiprotons are known sensitive to new physics: dark matter annihilations e.g. from new particles in supersymmetric or Kaluza-Klein Theories Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 5
Antihelium different appoaches for the explanation of the baryon asymmetry: dynamically: large CP violation is needed separation of matter and antimatter in the early universe measurement: bound on antihelium gives constraint for the distance between galaxies and antigalaxies (NO(!) production of antihelium in the matter universe possible) Antihelium/Helium Flux Ratio (95% C.L.) - -3-4 -5-6 -7-8 (a) (c) (c) (b) (d) (e) AMS-0 3 Years (a) Buffington etal. 98 (b) Golden etal. 997 (c) Badhwar etal. 978 (d) Alcaraz etal. 998 (e) Sasaki etal. 00-9 3 Rigidity (GV) Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 6
The AMS-0 Detector AMS-0 in the clean room @ CERN artist view of AMS-0 on the International Space Station > 0 3m 7t Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 7
AMS-0 Overview goals of AMS-0: precise spectroscopy of cosmic rays without interactions in the atmosphere on the ISS measurement/bounds on antimatter indirect dark matter search subdetectors: ( TRD ) Transition Radiation Detector classify particles by γ=e/m ( ToF ) Time of Flight trigger, velocity, de/dx Tracker + supraconducting Magnet (T) track reconstruction, momentum, de/dx ( ACC ) Anti-Coincidence Counter event selection next slide ( RICH ) Ring Image Cherenkov Detector precise velocity mesaurement ( ECal ) Electromagnetic Calorimeter shower shape and energy determination Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 8
Important Events for the ACC rejection of internal interactions rejection of external particles ACC ACC Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 9
ACC System PMT box, small B pos. scintillator panels PMT box, small B pos. clear fibers small ACC inefficiency needed (< -4 ) for measurement of antimatter with very clean single tracks reduce trigger rate, fast detector (ns): e.g. south atlantic anomaly Coupling Charged particle Coupling panels share lower and upper PMT PMT PMT Clear fiber WLS fiber WLS fiberclear fiber Scintillator Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p.
Light Signals scintillator with WLS fibers attenuation of clear fiber PMT quantum efficiency Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p.
ACC Hardware Parts 6 Bicron BC44 Scintillator Panels with inlaying Kuraray wave length shifting fibers 6 Y-shaped Toray clear fiber cables PMT side 6 Hamamatsu fine mesh PMTs, B tolerant (0.5T 65% gain) panel side Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p.
ACC Panel Production curing of glue glued panel machining of panel finished panel Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 3
Panel Classification entries [#] 4 3 channel 0 channel 3 Q C Q LED test of all entries [#] entries [#] 8 panels panel distribution Entries 0 Mean 8.7 RMS.83 cosmics LED 6 00 400 600 800 00 adc N pe = Q Q C LED σ LED 00 400 600 800 00 adc calculation of photo electron number: measurement of MOP with cosmics calibration with LEDs implemented in panels 4 0 4 6 8 0 4 number of photo electrons[#] material photo elec. AMS-0.0cm 0 AMS-0 0.8cm 9 Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 4
Coupling: WLS to Clear Fiber entries [#] 600 x Profile y Profile entries [#] 600 x Profile y Profile 500 500 400 400 300 300 00 0 wavelength shifting fiber: 0.9dB/m 00 0 clear fiber: 0.5dB/m 0-60 -40-0 0 0 40 60 angle [deg] 0-60 -40-0 0 0 40 60 angle [deg] acceptance angle matching of wavelength shifting fiber and clear fiber is important WLS: wide distribution due to reabsorption is also responsible for large attenuation Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 5
Space Qualification - PMTs TVT tank PMTs PMTs random frequency spectrum: 3.3g temperature [deg C] 60 40 0 0-0 Temperature requirements: operative: -30 - +45 C non-operative: -35 - +50 C PMTs did not change within 5% after Space Qualification -40 0 5 5 0 5 30 35 40 45 time [h] Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 6
PMT Selection for Flight amplitude [V] 0-0.0 channel 6 channel 8 classification with gain and p.e. number -0.0-0.03-0.04-0.05-6 -0.4-0. -0. -0.08-0.06-0.04 time [s] typical signal shape mounting in light and glass dust tight box Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 7
Complete System Test test of complete chain: panel + clear fiber + PMT show good results (mean: 6 photo electrons) Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 8
Preintegration entries [#] 45 40 35 entries: 59 mean: 0.99 width: 0.08 30 5 0 5 5 0 0.5 0.6 0.7 0.8 0.9...3.4.5 LED preintegration/system test successful preintegration: 99 ± 8 % ( after/before ) LED test comparison Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 9
Inefficiency Studies: Testbeam - Setup central slot slot test of slot and central region Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 0
Testbeam Inefficiency Measurement highest ADC counts from both PMTs on one panel for each event central 4.3 mm from slot.6 mm from slot slot signal ratio 0.9 0.8 fit to MOP position 0.7 central 0.6 0.5 ratio = 0.06cm.000 pos -.636cm +.00 slot 0 5 position [cm] Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p.
Signal Ratios entries: signal ratio.05 0.95 - ratio = -0.0076cm pos+ entries [#] mean: 0.99 RMS: 0.40 0.9 0.85 0.8 0.75 0.7 0.65 0 0 30 40 position [cm] central ratio of both PMT MOP signals on one panels vs. position 0 0.5.5.5 3 channel 3 / channel 4 Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. estimation of hit position distribution of signal ratios at the central position
Signal Model length [cm] 40 30 0. 0.9 length [cm] 40 30 0 P M T. 0.9 0.8 0.8 0 0-0.7-0.7-0 -30 P M T -40-40 -30-0 - 0 0 30 40 width [cm] 0.6 0.5 0.4-0 -30 P M T -40-40 -30-0 - 0 0 30 40 width [cm] 0.6 0.5 0.4 model for relative signal behaviour of one PMT model for relative signal behaviour for the highest value of both PMTs Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 3
Flight Electronics branches of signal processing: fast veto decision for level trigger with discriminator threshold charge and time measurement after trigger (ADC, TDC) Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 4
Flight Electronics: Calibration test pulse, Gain 5,.kΩ, 5nF 800 60pC pc 700 pc ADC counts [#] 600 500 400 300 00 0 gauging of ADC charge measurement with test pulses: high resolution for small charges test pulse, Gain 5,.kΩ, 5nF, side A Voltage [mv] 50 40 30 0 V = 0.0 thr+.76 0 0 5 5 0 5 30 35 40 delay [μs] time delay scan to get to the maximum signal of the ADC charge [pc] 800 700 600 500 400 300 0 0 50 0 50 00 50 Threshold calibration of thresholds for the discrimination in the TDC 00 0 0 0 500 00 500 000 ADC counts [#] Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 5
Flight Electronics ACC0 +WLS entries [#] 3 ACC +WLS 4 ACC 0 ACC ACC / ADC counts [#] 300 50 00 50 0 50 3RMS of pedestal - 0 0 00 300 400 500 600 700 800 900 00 ADC counts [#] 0 0 50 0 50 00 50 300 ACC0 / ADC counts [#] PMTs (ACC0/) connected to one panel no event missed out of 000 by using the highest of both values Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 6
Isotropic Particle Distribution isotropic particle toy MC distribution of travelled paths in scintillator thickness: 0.8cm signal ratio 6 5 lab measurement of rel. signal vs. angle: good agreement with theory beamtest: straight infall to panel space: isotropic particle distribution leads to longer path lengths in scinitillator 0 0 40 60 80 angle θ [deg] Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 7 4 3 theory
Inefficiency Model Inefficiency - -3 slot Testbeam MC: LeCroy MC: SFEA slot Inefficiency - -3 MC: LeCroy MC: SFEA -4-4 -5-5 -6 central -6 central -7-7 -8 - -5 0 5 Y position [cm] -8-40 -30-0 - 0 0 30 40 X position [cm] Data: Mean inefficiency for one complete ACC panel with complete system test results and isotropic particle distribution and testbeam electronics: 5-5 Simulation: use of testbeam spectra with extrapolation to small values, system test, flight electronics, position measurements, isotropic particle distribution, smearing of signal values: 5-6 Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 8
AMS-0 Cosmics: Eventdisplay AMS Event Display Run 5373/ 768 Wed May 7 :43:06 008 Front Side z x y Header Level DAQ z y x Header Level DAQ Particle TofTrd No 0 Id= p= -e+07± e+ M= 0± nan θ=0.63 φ=5.98 Q= β=-.000±.000 Coo=(-6.33,-0.6,-5.99) AntiC=-34.00 Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 9
Event Selection trigger entries [#] 7 6 5 effect of multiplexing in x direction entries: 88798 4 3 noise noise Tracker layer 5 distance (Δx +Δy ) / 0 0 30 40 50 60 tracker: hit -hit TR [cm] TRD time of hit in TDC for hit per event require for selection at least one hit within 80ns of trigger matching of TRD track with tracker: at least two tracker hits within 0.5cm one hit within 0.5cm in last layer before extrapolated hit position in ACC Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 30
AMS-0 Cosmics entries [#] 6 5 ACC: 3066 TRD: 4978989 entries [#] 4 3 entries: 3066 4 3 0 0. 0. 0.3 0.4 0.5 0.6 0.7 0.8 0.9 cos(zenith) zenith angles for all good TRD and for ACC events surviving all cuts 0 00 000 3000 4000 ADC counts [#] highest ADC value for each event surviving tracker cuts: no events below 30 (3RMS) Inefficiency < 7.7-5 Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 3
AMS-0 Cosmics: Signals ADC counts [#] 4000 3500 3000 upper PMTs ADC counts [#] 4000 3500 3000 lower PMTs 500 000 500 000 500 500 00 500 entries: 987-00 500 entries: 98-0 -3 - - 0 3 φ [rad] 8 7 6 3 5 4 not very well configured: mix of EM, QM and FM different settings and conditions Search for Antiparticles in Cosmic Rays 0-3 - - 0 3 φ [rad] Ph. von Doetinchem Hausseminar 08/06/06 p. 3
Position Matching: ACC/Track z [cm] 0 50 0-50 position of hits with small signals 5 6 7 8 3 4 - ACC sector from Track [#] 8 7 6 5 4 3 - -0 entries: 8 - entries: 8-3 - - 0 3 φ [rad] 3 4 5 6 7 8 ACC sector [#] position of hits below 30 very close to adjacent panel: adjacent panels show normal signals TRD/tracker matching not precise enough scattering in detector no events missed out of 3000 ACC events considering the complete ACC Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 33
Antihelium with AMS-0 larger angular acceptance of ACC than TOF check for the ability to measure particles between triggers with the ACC which could spoil the charge determination toy MC with TOF, Tracker and ACC with isotropic particle distribution and without magnetic field Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 34
Antihelium with AMS-0 TOF external event TOF trigger event distance between hits is interesting for charge measurement efficiency TOF Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 35
Antihelium with AMS-0 close hit: 0m< hit -hit <0.05m TOF ACC TOF probability [%] 3 - - -3 ext distance in tracker layers between TOF trigger events and external events 0 3 4 5 6 7 8 number of close hits Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 36-4 probabilty for close hits (<5cm) not longer than 80ns from trigger @ khz external hits can be nearly completly excluded to spoil charge measurement
Antiprotons with TRD, TOF and Tracker Electron Rejection 90% p-efficiency Electron Rejection 70% p-efficiency.5.5 3 3.5 4 4.5 5 Energy [GeV] 0 50 0 50 00 50 Energy [GeV] electron rejection from time resolution of TOF (0ps) due to different masses electron rejection from TRD from Lorentz factor γ=e/m due to different masses Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 37
Antiprotons with TRD, TOF and Tracker sr - s - m - ] - Flux [GeV 4 3 - - -3 p, AMS, 95 days p, AMS, 95 days conv. Galprop ] + Antiproton Fraction [p/p -3-4 AMS, 95 days AMS, sys. error Galprop + DM DM, DarkSUSY conv. Galprop m / = 6 GeV, m = 560 GeV 0 tanβ= 40, μ>0, A = 0 0 DM signal boost factor:.0 IMAX Caprice 98 Caprice 94 BESS 95/97 BESS 0 Heat Pamela (preliminary) -4-5 -6 AMS0 protons IMAX antiprotons Caprice 94 antiprotons Caprice 98 antiprotons BESS 95/97 antiprotons BESS 0 antiprotons combined antiprotons -5-7 Energy [GeV] Energy [GeV] measurement over 3 years with: good measurement of antiprotons without acceptance = 0.4m sr electromagnetic calorimeter possible 63% efficiency % systematic errors to the knowledge of detector properties tracker resolution is not important in this energy range (σ p =0.04%/GeV p.5%) Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 38
PEBS Cosmic Rays in the Atmosphere Positron Electron Balloon Spectrometer detector proposal: cosmic ray measurements @ North- or Southpole balloon in 40km altitude in the atmosphere and magnetic field detector properties: flight time: 0days (total) acceptance: 0.4m sr magnetic field: T weight: < t Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 39
Analysis Scheme PLANETOCOSMICS simulate at South Pole extract galactic fluxes calculate errors compare secondary muons with BESS @ Ft. Sumner, TX verify simulation solar Modulation force field approximation isotropic distribution in 40km height Earth s magnetic field and atmosphere (IGRF, NRLMSIS00) produce spectra of galactic cosmic ray GALPROP DarkSUSY Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 40
Air Shower GeV proton use of program package: PLANETOCOSMICS based on GEANT4 atmospheric model: NRLMSISE00 magnetic field: IGRF 005 detection planes around the Earth start particles in 500km altitude Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 4
Properties of the Atmosphere Temperature [deg Celsius] 0 0-0 -40-60 C ] depth [g/cm 3 3.7g/cm -80-0 - -0 0 0 30 40 50 60 70 80 Altitude [km] kinetic gas temperature of the atmosphere at latitude -75, December (Southpole) - 0 0 30 40 50 60 70 80 Altitude [km] depth (integrated density) of atmosphere for zenith angle = 0, latitude -75, December (Southpole) Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 4
Radiation Lengths number of radiation length.5.5 0.5 0 0 0. 0.4 0.6 0.8 cos(zenith) number of crossed radiation lengths depends on zenith angle distribution of crossed radiation lengths before 40km during summer at Southpole using an isotropic particle distribution Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 43
Magnetic Field Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 44
Geomagnetic Cut-off zenith [deg] 90 80 70 60 50 40 30 0 Ft. Sumner, Texas 0 0 50 0 50 00 50 300 350 azimuth [deg] 0 8 6 4 8 6 4 0 cut-off [GV] geomagnetic cut-off for particles with zenith angle = 0 geomagnetic cut-off depends on zenith and azimuth at each location Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 45
BESS Muon Data in Texas sr - s - m - ] - Flux [GeV 37000 m, 4.7 g/cm 30000 m, 3 g/cm - BESS 4.68 g/cm BESS 3.4 g/cm - Energy [GeV] good agreement of simulated secondary muons with BESS data at Ft. Sumner simulated angular distribution for muons in 37km altitude Simulation works, now Southpole Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 46
Fluxes in different Altitudes integrated flux (-30GeV): primary particles integrated flux (-30GeV): secondary particles Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 47
Detector Acceptance m - s - ] - Flux [sr 4 3 primary positrons, 40000m secondary positrons, 40000m Entries [#] 4 - - -3-4 -5-6 3-7 0 0. 0. 0.3 0.4 0.5 0.6 0.7 0.8 0.9 cos(zenith) angular distribution of secondary and primary positrons 0 0. 0. 0.3 0.4 0.5 0.6 0.7 0.8 0.9 cos(α det ) angular acceptance of PEBS works as filter on secondaries Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 48
Atmospheric Attenuation in 40 km total antiprotons / generated antiprotons total positrons / generated positrons atmosphere is electromagnetically much more effective Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 49
Detector Properties electron/ antiproton rejection from TOF Electron Rejection 90% p-efficiency.5.5 3 3.5 4 4.5 5 Energy [GeV] Probability E e + e - - - -3-4 -5-6 -7-8 -9 - - - -3 σ p =0.94%/GeV p.3% 50 0 50 00 50 300 Energy [GeV] electron/ positron rejection from tracker electron/ antiproton rejection from TRD Electron Rejection Factor 3 70% e-eff. x8 Layer 80% e-eff. x8 Layer 90% e-eff. x8 Layer Proton Rejection Factor 3 70% e-eff. x8 Layer 80% e-eff. x8 Layer 90% e-eff. x8 Layer proton/ positron rejection from TRD 50 0 50 00 50 E Beam / GeV 50 0 50 00 50 E Beam / GeV Ecal rejections p + /e + and e - /p - : 5000 (70% Efficiency) Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 50
Total Number of Particles [#] PEBS N 9 8 total p, PEBS, 0 days + total p, PEBS, 0 days [#] PEBS N 9 8 + total e, PEBS, 0 days - total e, PEBS, 0 days 7 7 6 6 5 5 4 4 3 3 Energy [GeV] Energy [GeV] protons and antiprotons electrons and positrons Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 5
Composition [%] primary antiprotons secondary antiprotons [%] primary positrons secondary positrons muons protons - - total p, PEBS, 0 days prim. p altitude, PEBS, 0 days sec. p altitude, PEBS, 0 days - wrong e, PEBS, 0 days - wrong μ, PEBS, 0 days - wrong π, PEBS, 0 days wrong p +, PEBS, 0 days pions electrons Energy [GeV] - - + total e, PEBS, 0 days + prim. e altitude, PEBS, 0 days sec. e + altitude, PEBS, 0 days wrong p +, PEBS, 0 days - wrong e, PEBS, 0 days electrons Energy [GeV] antiprotons positrons using the according rejections and efficiencies for each type Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 5
Antiprotons sr - s - m - ] - Flux [GeV 4 3 - - -3 p, PEBS, 0 days p, PEBS, 0 days conv. Galprop ] + Antiproton Fraction [p/p -3-4 PEBS, 0 days PEBS, sys. error Galprop + DM DM, DarkSUSY conv. Galprop m / = 6 GeV, m = 560 GeV 0 tanβ= 40, μ>0, A = 0 0 DM signal boost factor:.0 IMAX Caprice 98 Caprice 94 BESS 95/97 BESS 0 Heat Pamela (preliminary) -4-5 -6 AMS0 protons IMAX antiprotons Caprice 94 antiprotons Caprice 98 antiprotons BESS 95/97 antiprotons BESS 0 antiprotons combined antiprotons -5-7 fluxes Energy [GeV] fraction Energy [GeV] using the according rejections and efficiencies for each type with systematic errors for detectors of 3% and 5% for the atmosphere Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 53
Positrons sr - s - m - ] - Flux [GeV 4 3 - - -3-4 -5-6 AMS-0 electrons AMS-0 positrons HEAT 94/5 positrons + e, PEBS, 0 days - e, PEBS, 0 days conv. Galprop - e + e + +e Positron Fraction - PEBS, 0 days PEBS, sys. error HEAT AMS0 combined Galprop + DM DM, DarkSUSY conv. Galprop m / = 60 GeV, m = 560 GeV 0 tanβ= 40, μ>0, A = 0 0 DM signal boost factor: 0.0-7 fluxes Energy [GeV] fraction Energy [GeV] using the according rejections and efficiencies for each type with systematic errors for detectors of 3% and 5% for the atmosphere Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 54
Conclusion ACC system for AMS-0 works! scintillators, clear fibers, PMTs: good flight electronics: good preintegration done! cosmic test of AMS-0 good inefficiency of about -5 for antimatter search PEBS prospects are promising! atmospheric and magnetic simulations work fine good capabilities to measure positrons and antiprotons and Southpole or Northpole Ph. von Doetinchem Search for Antiparticles in Cosmic Rays Hausseminar 08/06/06 p. 55