AMS as an Astroparticle Physics ExperimentAMS as an Astroparticle Physics Experiment

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김 귀년

Astroparticl Physics is

Connecting Quarks with the Cosmos

Periodic System of Elementary ParticlesPeriodic System of Elementary Particles

e-N eutrino e

-N eutrino

E lec tron eMuon Tau

C harge -1 C harge 0D ow n

B ottom

U p uC harmTop

C harge +2/3 C harge -1/3

ct b

sd1st Family:

2nd 3rd

G ravitation

Weak Interac tion

E lec tromagnetic Interac tion

S trong Interac tion

Family:Family:

uudduu

uudd dd NeutronNeutronNeutronNeutron

ProtonProtonProtonProton

e-N eutrino e

-N eutrino

E lec tron eMuon Tau

C harge -1 C harge 0D ow n

B ottom

U p uC harmTop

C harge +2/3 C harge -1/3

ct b

sd1st Family:

2nd 3rd

G ravitation

Weak Interac tion

E lec tromagnetic Interac tion

S trong Interac tion

Family:Family:

Inflation(Big Bang plus

10-34 Seconds)

Big Bang plus 300,000 Years

Big Bang plus 15 Billion Years

What Powered the Big Bang?

Nowgravitational waves

light

What is the Dark Energy?

We do not know what 95% of the universe is made of!

Cosmic Rays

What are cosmic rays? Elementary particles,

nuclei, EM radiation of extra-terrestrial origin, including , ,

At the edge of the Earth's atmosphere

50% protons, 25% , 13% C/N/O nuclei, <1% e-, <0.1%

Discovery of cosmic rays Victor. F. Hess, Nobel Prize

in 1936

Where Cosmic Ray come from? Where Cosmic Ray come from?

S. Swordy

CR ASTRONOMY

Cosmic Rays composition in spaceCosmic Rays composition in space ~88% proton, ~ 9% He nuclei, ~88% proton, ~ 9% He nuclei,

~1% Z > 2 nuclei, ~ 2% electrons, <0.1% gamma~1% Z > 2 nuclei, ~ 2% electrons, <0.1% gammaDevelopment of Cosmic-Ray Air-Shower

AMS AMS 실험은실험은

국제우주정거장에서 수행되는 세계최초의 고에너지물리실험국제우주정거장에서 수행되는 세계최초의 고에너지물리실험 20072007 년 년 77 월에 국제우주정거장월에 국제우주정거장 (ISS) (ISS) 설치되어 설치되어 3-5 3-5 년 동안 수행년 동안 수행 1414 개국 개국 4646 개 기관의 개 기관의 200200 명 이상의 과학자와 산업체가 참여하는 명 이상의 과학자와 산업체가 참여하는

다국적 국제공동연구다국적 국제공동연구

International CollaborationInternational Collaboration~200 scientists + dozens of contractors from 14 countries

Spokesperson: TING, Samuel C. C.

AMS 02 AMS 02 검출기의 특징검출기의 특징

► 우주에서 수행되는 최초의 고에너지 물리실험 검출기로서 3-5 년 동안 무인 우주실험에 사용됨으로 여러 가지 제약 점이 있다 .

질량 : 6200 kg 이내크기 : ~ 3.2 x 2.7 m소모전력 : 2 kW 이내이륙시 중력가속도 : 9 g작동온도 범위 : -180o + 50oC유출 기체 한계 : <10- 12 g/s/cm2

Trigger rate: ~ 200 HzData rate: ~ 3 Mb/s

질량 : 6200 kg 이내크기 : ~ 3.2 x 2.7 m소모전력 : 2 kW 이내이륙시 중력가속도 : 9 g작동온도 범위 : -180o + 50oC유출 기체 한계 : <10- 12 g/s/cm2

Trigger rate: ~ 200 HzData rate: ~ 3 Mb/s

AMS02 : technological challengeAMS02 : technological challenge

AnticoincidenceAnticoincidence: veto plastic scintillators used in Trigger

Time of FlightTime of Flight: 2x2 planes of scintillator hodoscopeResolution T=120 ps .

Used in Trigger Velocity measurement L/ct1-ct2 /3.5% E/dx measurements

TrackerTracker : 8 planes of double sided Silicon (6 m2). 110 and 208 pitchResolution =17 in bending plane and 30 non bend.

Rigidity pc/Ze=0.3BR measurements up to ~3 TeVdE/dx ~ Z2 measurement.Conversion of gamma e+e-

Superconductive Magnet:Superconductive Magnet: B

dipol =0.87 Tesla I~459A

Size: d=1.2m l=0.8 m; Mass 2.3 tcooled to 1.8K by superfluid He (2500 l)

AMS02 : technological challengeAMS02 : technological challenge

Ring Image Cherenkov Detector:Ring Image Cherenkov Detector: radiators (NaF n=1.336 and Aerogel n=1.035) +PMT's

velocity measurements (up to 20 GeV / 0.1%) Absolute charge measurements N

photons~Z 2 (=0.2)

up to Z=26

Electromagnetic Calorimeter:Electromagnetic Calorimeter: Pb+ scintillators fibers readout by 324 PMT's (2x2cm readout granularity)Overall 18 x-y planes. Size 65x65 cm2 . Weight 640 kg. Thickness ~16 X

o and ~ 0.5

nucl. .

Energy measurements for leptons dE/E=0.03+0.13/E[GeV]

Used in gamma triggere, / h separation ~10 3 E=1-1000 GeV

Transition Radiation Detector:Transition Radiation Detector: 20 layers of 6 mm straw tubes(Ntot=5248) filled with Xe/CO2 (44 kg Xe+3.7kg CO2) interposed with fleece radiator (22 mm).

dE/dx measurements .Separation e/h ~10 3 - 10 2 p=1-250 GeV

AMS AMS 실험 목적은실험 목적은 우주에서의 반물질 검색우주에서의 반물질 검색 (( 세계 최고의 감도로세계 최고의 감도로 , , 세계 최초세계 최초 ))

– 우주 대폭발 ( 빅뱅 ) 시 물질 / 반물질 비 =1– 현재 우주는 대다수 반물질이 아닌 물질로 구성– 만일 100 억분의 하나가 반물질로 자연에 존재할 경우 , 이를 측정하고자 함 .– 현재 한계는 < 1.1 x 10-6 ( <100 GeV) - AMS 01 실험과 BESS 실험에 의하여

암흑물질 암흑물질 (( 우주물질의 우주물질의 90%90% 가량가량 ) ) 탐색탐색 (( 우주에서 직접 수행하는 세계 최초 실우주에서 직접 수행하는 세계 최초 실험험 ))– 암흑물질의 충돌로 반물질인 반양성자 , 양전자 , 광자 등이 다수 생성되며 ,– 이들의 스펙트럼에 bump 로 나타남 .– 따라서 , 반물질의 스펙트럼을 측정

우주선의 기원에 대한 연구우주선의 기원에 대한 연구 (( 직접 우주에서 수행하는 첫 실험직접 우주에서 수행하는 첫 실험 ))– 갤럭시 내에서 입자전파 현상에 대한 정보 제공 – 109 동위원소를 측정 (D, He, Li, Be, B, C 등 )– 이들의 측정 시 배후과정인 보통의 우주선 측정

직접 직접 s s 쿼크들로 구성된 쿼크들로 구성된 strangeletstrangelet 를 탐색를 탐색 (( 가설을 최초로 검증가설을 최초로 검증 ))– Strangelet 는 중성별과 같이 보통의 상태에서는 존재하지 않은 특별한 상태의 물질– S 쿼크는 실험실에서만 검출되었음

고에너지 감마선 검출고에너지 감마선 검출 (( 최고 에너지의 감마선 측정 능력 보유최고 에너지의 감마선 측정 능력 보유 ))

Is the Universe Composed only of Matter?

How to explain Baryon Asymmetry?Principles of Baryogenesis (D.Sakharov 1967)three conditions have to be fulfilled: non-conservation of baryons Violation both C and CP Deviation from thermal equilibruim

Different models of baryogenesis:✔Grand Unified Theory (GUT) inspired (D.Sakharov)✔SUSY condensate (I.Afleck et al)✔Spontaneous baryogenesis (A.Cohen et al)✔ Etc

Local domains of antimatter are not excluded by baryogenesis.antistars, antiblackholes...

Present bounds are coming from gamma rays and CMB spectra lB>10 Mpc

Unambiguous proof would be an observation of heavy (Z>=2) anti-nuclei in Cosmic rays (A.Dolgov et al)

Anti-matter Domain

Anti-CR

Us

Matter Domain

(1) Indirect Search for Antimatter: Photons

If the Universe contains regions of antimatter and matter,annihilation radiation at the boundaries should occur viathe process:

This should result in:• a distortion of the cosmic microwave background (COBE measures a quite isotropic blackbody radiation for a distance up to about 10 Mpc)• a signal in the extragalactic diffuse -ray background induced by the (redshiffed) annihilation photons.Non-observation of this radiation excludes large zones of antimatter in our supercluster of galaxies.

sesNN ',,',0

ee

(2) Direct Searches for Antimatter

Antiproton measurements do not provide evidence for extragalactic antimatter.

The p-flux near the earth can be explained mainly by secondary interactions of cosmic rays depending on: - incident spectra - interstellar gas composition - solar modulation at lower energies

However the probability to produce antinuclei by high energy interactions falls drastically with the amount of antinucleons. (more than 104 per antinucleon) - Discovery of antinucleus (e.g. antihelium) evidence for cosmologically significant amounts of antimatter. - Discovery of anticarbon nuclei antistars ?

Up to now, No antinucleus with Z2 has ever been found in the cosmic radiation.

NHe/NHe = 1.1·10-6 , R ( pc/Ze)<100 GVSame spectrum for He, He

Any Spectrum from He

Antihelium Search (AMS 01 Results)(Ref. Phys. Lett. B461(1999)387-396)

Antimatter Search Results for Heavier Nuclei

AMS02 discovery potential : AntimatterAMS02 discovery potential : Antimatter

Antimatter search Negative Z >=2 nuclear background He

secondary /He < 10 -12 ;

AMS01 limit 10 – 6, AMS02 expected ~10 -9 is limited by statistics

Dark Matter Search Dark Matter Search

►Direct search: nuclear interactions with detector (ground based experiments)► Indirect search: products of annihilation (in Space )

AMS 02 -indirect Search for the relic Dark Matter in Space

Supersymmetric Dark Matter is a prime candidateLightest Supersymmetric(mSUGRA) Particle (LSP) is heavy (>100GeV) stable (R parity conserved)weakly interacts with baryonic matter (WIMPS) < 10-42 cm2

can annihilate and produce stable SM particles (p,antiprotons, e+.e-, )

Different candidates : axions, magnetic monopoles etc.

Neutralino Dark MatterNeutralino Dark Matter

Properties of Neutalino Mass: ~ 100 GeV

Interactions: weak

The “typical” WIMP (but note: neutralinos are Majorana fermions – they are their own anti-particle)

• Direct detection: see Prof. S. Kim’s talk

• Indirect detection: annihilationin the halo to e’s: AMS-02, PAMELA…

in the center of the galaxy to ’s: GLAST, AMS/, telescopes,…

in the center of the Sun to ’s: AMANDA, NESTOR, ANTARES,…

Neutralinos:

Supersymmetric Dark MatterLSP is a bino-like neutralinoneutralino is a spin ½ Majorana particle and can annihilate

Neutralino is the Dark Matter candidate.

Signature of Dark Matter: eSignature of Dark Matter: e++, p, , p,

Background Cosmic Ray spectra is dominant by SM stable particles : p, He, e-Have chance to see signal from annihilation in e+, p and components where backgrounds from nuclear interactions is smaller.

Flux for i -component is :

Annihilation of neutralino

Monochromatic gamma lines E =m m mz

2/4m

Signal signatures : cross sectionsSignal signatures : cross sections

After hadronization and decays ->stable particles with continuum spectra

< eff

V> thermal averaged cross section depends strongly on tan , m

1/2 (m~0.4m

1/2, s~1/m

2) and m

o

Tree diagrams

1 loop diagrams

Dominant channel>90%

Hard Positron SignalHard Positron SignalTurner, Wilczek (1990)

Kamionkowski, Turner (1991)

Best hope: e+e- If are Majorana-like ( Pauli Jinit = 0), This process is highly suppressed

Next best hope: W+W-, ZZ e+…Problem: conventional wisdom in simple models,≈ B

ino, does not couple to SU(2) gauge bosons

We are left with soft e+: bb ce+n…

AMS02 discovery potential : Dark MatterAMS02 discovery potential : Dark Matter

Hard PositronsMost promising channel.Specific bump at ~ 5-100 GeV.Small contamination and large significance

A.Baltz et al. Astro-ph/9808243MSSM scan

Signal flux is ~ 1/m4 . For the high m one

needs larger Boost factors to see signal

m=130 GeV m=336 GeV

(by V. Zhukov University of Karlsruhe)

AMS02 discovery potential : DarkMatterAMS02 discovery potential : DarkMatter

Antiprotons AntiDeutronsDifficult case since the shapes of the signal and background are similar and at the low energy part(<10GeV) flux is prone to the solar modulation and the background is not well defined

p+n->d Significance can be better than for antiprotons

(by V. Zhukov University of Karlsruhe)

Signal signatures : DM halo profile Signal signatures : DM halo profile

From rotation curves - neutralino is spherically distributed around galactic center.Navarro, Frenk, White type Dark Matter halo profile :

define the slope

0 - local density 0.3-0.7 GeV/cm3

a -scale parameter (depends on 0)

We are here ro~ 8kpc

Local 'clumps ' of DM can significantly increase signal from the Dark Matter annihilation (Boost factors)

J.F.Navarro Et al Ap.J.462(1996)

L.Bergstrom et al astro-ph/9806072

Composition and Energy Spectrum of Conventional Cosmic Rays

The relative abundance of particles, elements and isotopes is related to:• Primordial nucleosynthesis for the particles created just after the Big-Bang:

• Astrophysical sources accelerating primary particles:

• Interactions with interstellar gas create secondaries:

(Spallation), 10Be/9Be ratio depends on propagation time• Propagation described by the Leaky Box model

LiHeHeDep 734 ,,,,,,

FeOCHepe ,,,,,

BBeLippe ,,,,,

AMS02 discovery potential : CR compositionAMS02 discovery potential : CR composition

AMS 02 will measure chemical compositions up to ~1 TeV/nand will constrain a propagation model.

Propagation model:- describes propagation (diffusion, convection, reacceleration) of cosmic ray particles in galaxies- calculates nuclear interaction of primary produced particles with interstellar medium(ISM)

Predicts abundances of element. Estimates backgrounds.

I.Moskalenko and A.Strong Astro.J 509 (1998)

Main parameters of the model:diffusion constant, size of ISM disk, density of the ISM, reacceleration speed, etccan be fixed by ratios of abundances

AMS02 discovery potential : CR compositionAMS02 discovery potential : CR composition

1 year

10Be (t1/2

=1.5myr) / 9Bewill allow to estimate thepropagation time andsize of the ISM

B is secondary produced in nuclear interaction, C is primary produced in stars. B/C is sensitive tothe diffusion constant

3He/4He ratio is sensitive to the densityof the ISM

6 months 1 day

High Energy -ray Physics

• Astrophysical sources of -rays:

- point sources: blazars, GRBs, and pulsars - diffuse sources: ray background, from WIMP annihilation

GRBsGRBs

PulsarsPulsarsAGNsAGNs

Gamma ray astrophysics powerful tool to test the Univers

AMS02 discovery potential: Gamma AMS02 discovery potential: Gamma astrophysicsastrophysics

Detailed study of gamma spectrum.Extra Galactic F ~ E-2.7 and galactic component F ~ E-2.1

Probe the model of gamma rays production and propagation.

Study gamma rays profile vs galactic latitude and longitude.

●● Gamma from neutralino annihilation reflects the DM halo profile.

Monochromatic lines from neutralino annihilation->at E=m can

constrain the clumpiness.Experimental data , models and AMS02 projection

Diffuse gamma spectrum up to few hundred GeV

A.W.Strong Et al. Astr.J.537 (2000)

AMS02 discovery potential : Gamma astrophysicsAMS02 discovery potential : Gamma astrophysics

Point sources: Active Galactic Centers(AGN), pulsars etc.EGRET(1991) third source Catalog

Point like sources observed by EGRET at E<30GeV 271 sources >100MeV

AMS02 angular resolution:< 2.5o ECAL mode E>10GeV< 0.1o Tracker conversion E >10GeV(EGRET 2-3o GLAST 0.1o)Acceptances: A(=0) 1750 cm2 ECAL

450 cm2 Tracker conversion (EGRET 1500cm2,GLAST 12000 cm2)

Time variable point sources: Gamma Ray Bursts(GRB), blazars

Source identification at E>20GeV

Energy spectra of sources

Sensitivity of –ray detectors

Energy vs Time for X and Gamma ray detectors

SummarySummary

• AMS-02 : an exciting challenge - Cosmic rays will be measured with order of magnitude higher precision than before and up to the TeV region - Search for antinuclei (antihelium sensitivity: 10-9) - Search for dark matter - High energy gamma ray physics (0.3 < E<100 GeV)

- Physics beyond the standard model- Astrophysics- Strangelets and other exotics- ????

The Space Experiment PAMELAThe Space Experiment PAMELAMirko Boezio – INFN TriesteMirko Boezio – INFN Trieste

The Satellite: Resurs DK1The Satellite: Resurs DK1

TRDTRD

CalorimeterCalorimeter

ToFToF

AnticoincidenceAnticoincidenceshieldshield

Shower tail catcher Shower tail catcher scintillatorscintillator

Magnetic Magnetic spectrometespectrometerr

PAMELA StatusPAMELA StatusDetectors are ready and compling with the design performances

Detectors tested at PS / SPSTest facilities as Prototypes and in FM configuration

Mass/Termal ModelsQualified, March-May 2003

Integration of PAMELA TechnologicalModel completed and delivery toRussia underwayIntegration of PAMELA FMunderway at INFN – Roma2

The PAMELA Launch is in 2004 from Baikonur

PAMELA CapabilitiesPAMELA Capabilities

PAMELA will explore:Antiproton flux 80 MeV - 190 GeVPositron flux 50 MeV – 270 GeVElectron flux up to 400 GeVProton flux up to 700 GeVElectron/positron flux up to 2 TeVLight nuclei (up to Z=6) up to 200 GeV/nAntinuclei search (sensitivity of 10-7 in He/He)

Cosmic-ray Antimatter SearchCosmic-ray Antimatter Search

AGNsAGNs

SNRsSNRs Cold Dark MatterCold Dark Matter

PulsarsPulsars

GRBsGRBs

Tests of Quantum Tests of Quantum Gravity effectsGravity effects

Cosmological Cosmological -Ray Horizon-Ray Horizon

The MAGIC Physics TopicsThe MAGIC Physics Topics

Origin of Origin of Cosmic Cosmic RaysRays