AMS-02 and Dark Matter SearchAMS-02 and Dark Matter SearchNicolò MasiNicolò Masi

May 2012May 2012Bologna University and INFN

AMS-02, briefly

MatterMatter Anti-MatterAnti-Matter

An Improved Version of AMS-01

Antimatter

Astrophysics, Dark Matter

Strangelets

TOF consists of 4 plastic scintillator TOF consists of 4 plastic scintillator planes, 2 above and 2 below the planes, 2 above and 2 below the magnet.magnet.The counters of adjacent planes are The counters of adjacent planes are orthogonal.orthogonal.The number of counters per plane has The number of counters per plane has been reduced to 8, 8, 10, 8 counters to been reduced to 8, 8, 10, 8 counters to reduce the weight (34 scintillators). reduce the weight (34 scintillators).

Each TOF counter is composed by: Each TOF counter is composed by: • a plastic scintillator a plastic scintillator 1 cm thick and 1 cm thick and around 120 cm long (Eljen-Technology around 120 cm long (Eljen-Technology type: Ej-200), type: Ej-200), • read at both ends by 2 read at both ends by 2 independently powered independently powered photomultiplier tubes photomultiplier tubes (fine-mesh (fine-mesh Hamamatsu R5946 with max spectral Hamamatsu R5946 with max spectral response at 420 nm),response at 420 nm),• connected with transparent light connected with transparent light guidesguides..

Hamamatsu fine-mesh

R5946

AMS-02 Chronology• CERN: Test beam • ESA (Estec): CR Muons• CERN: Permanent Magnet, new test beam

and calibration• NASA (Cape Kennedy) - Final Step – CR

Muons • On board – Endevour STS-134• In space on ISS

February 2010

May 2010

2008 - 2010

August 2010 – February 2011

March 2011

May 2011

Lower TOF pre-integration(CERN, Geneva, Switzerland)

AMS at Cape Kennedy 2011 Launches

Date: May 9Mission: STS-134

Launch Vehicle: Space Shuttle Endeavour

Launch Site: Kennedy Space Center - Launch Pad 39°

STS-134 Description: Space shuttle Endeavour will deliver an EXPRESS Logistics Carrier-3 (ELC-3) and the Alpha Magnetic Spectrometer (AMS-02) to the ISS

ESA Astronaut: Roberto Vittori

Go baby go!

Beyond the SM: Dark Matter

13

Dark matter:is inferred to exist since 1934 from gravitational effects on visible matter and background radiation, undetectable by emitted or scattered em radiation. According to observations of structures larger than galaxies, as well as Big Bang cosmology interpreted under the Friedmann equations and the FRW metric, DM accounts for 23% of the mass-energy density of the observable universe. Ordinary matter accounts for only 4.6%.

Local Evidences:• Galactic Rotation Curves• Milky Way warp due to dark satellite galaxies • Dynamics of Galaxy Clusters• X-Ray Cluster Emission• Strong Gravitational Lensing• Anomalous Cosmic Ray Fluxes

Cosmological Evidences:• CMB Acoustic Peacks (from WMAP and PLANCK)• Structure Formation and Evolution

Local Galactic Evidences

• From the Kepler’s law, for r much larger than the luminous radius, you should have v r∝ -1/2.

• Instead, it is flat or rises slightly.

M grav /M vis

• The Bullet cluster (1E 0657-56) consists of two colliding clusters of galaxies. Studies of the Bullet cluster (August 2006), provide the best evidence for the existence of DM. At a statistical significance of 8σ, it was found that the spatial offset of the center of the total mass from the center of the baryonic mass peaks cannot be explained with an alteration of the gravitational force law.

• It provides "evidence against some of the more popular versions of Modified Newtonian Dynamics (MOND)" .

• VIRGOHI21 is an extended region of neutral hydrogen (HI) in the Virgo Cluster discovered in 2005. Analysis of its internal motion indicates that it may contain a large amount of DM, as much as a small galaxy, but no stars: the first Dark Galaxy.

Dynamics of galaxy cluster

Virial theorem

U = 2K K = i mi vi

2

U ~ GM2/R

X-ray cluster & Lensing

Hydrostatic equilibrium:

Beta model:But X-ray emission measures the temperature and Mgrav/Mvis = 20

Strong Gravitational Lensing

Cosmological Scale Evidences:WMAP results

Results depend on SNe Ia and Hubble parameter

Universe Curvature

Baryon density

Matter density

Acoustic peacks: barionic vs non barionic matter

mh2=0.135±0.009m=0.27±0.04

Bh2=0.02±0.002 B =0.04±0.01

Nature 458, 607 (2009)

Positron fraction

Some Clues: PAMELA

Exprimental data show that the cosmic ray fluxes of positron,

antiprotons and gamma rays are not quite in agreement with SM

expectations

Neutralino 𝝌WIMP Mass Region: 100 GeV ÷ 10 TeV

(<100 TeV)Axion Mass Region:

10 μeV÷1 meV

Statistic: dirac or majorana fermion, boson

S= 0,1/2, 1, 3/2, 2

Exotic Candidates

Cosmology 2Boltzmann

Equation on FRW background

Condition of Departure from

Equilibrium: Freeze out

Non-relativistic limit

Relativistic limit

Yield

Thermally averaged cross section

Cosmology Boltzmann

Equation in Yield

Neutralino

Nonthermal Production: from Oscillating Field on

Cosmological Background

DM particle density

DM density parameter

Detection

Two basic ways to detect WIMP dark matter which is present in the halo of our Galaxy

1) Direct detection: the possibility to detect the recoil energy of the nuclei of a low–background detector as a consequence of their elastic scattering with a WIMP.

One possible signal arises if the solar system itself is moving relative to the stationary halo of WIMP as it orbits around the Milky Way center.

2) Indirect detection: to detect products of the annihilation of DM particles, either in the galactic halo or in celestial bodies (namely the Earth and the Sun): the signal can

consists of photons, neutrinos and antimatter (positrons, antiprotons and antideuterons)

Direct DetectionScattering

Rate

• This recoil can be detected in some ways :

Electric charges released (ionization detector) Flashes of light produced (scintillation detector) Vibrations produced (phonon detector)

Anything above the blue lines is now excluded

1000

Low energy effective Lagrangian for WIMP-quark interaction

scalar interaction

5 5( ) ( ) ( ) ( ) ....q qL f qq d q q

spin-dep. interaction

• The other terms are velocity-dependent contributions and can be neglected in the non-relativistic limit for the direct detection.

• The scalar interaction scales with the atomic weight and almost always dominates for nuclei with A > 30.

q

q

qq

Neutralino

MSSM: Neutralino•The exact properties of each neutralino will depend on the details of the mixing but they tend to have masses in the order of 300-600 GeV and couple to other particles with strengths characteristic of the weak interaction. •In this way they are phenomenologically similar to neutrinos. In fact they are Majorana fermions and not directly observable in particle detectors at accelerators.Some MSSM Parameters In the basis 0 0 0

1 2( , , , )B W H H

1

2

0 cos sin sin sin0 cos cos sin cos

cos sin cos cos 0sin sin sin cos 0

Z W Z W

Z W Z W

Z W Z W

Z W Z W

M M MM M M

M MM M

0 0 0 01 2 3 1 4 2i i i i iN B N W N H N H

: ratio of vev of the two neutral Higgs

: Higgsino mass parameter

: Bino, Wino mass parameters

SUSY dependence

Upper bounds now enlarged by LHC results

Gaugino

Higgsino

Mixed

Neutralino: Indirect Detection Neutralino Annihilation channels

And antideuteron

Clear Signal!

No Dark Matter Signal!

Signatures of SUSY DM in the Cosmic Ray Spectra: positrons and antiprotons

PAMELA results on the Cosmic-Ray Antiprotons and positrons Fluxes

Channels: bb, tt, gg

Secondary Signatures: photons and antideuterons

Since EGRET

Gamma Excess

e+ Primary fluxes: DM vs astrophysical sources

Diffuse emission

Antideuteron

M = 0.1 TeV

M = 1 TeV

M = 10 TeV

Light Dark Matter Not Light Dark Matter

MED propagation and NFW profile

MIN, MED, MAX propagation sets

Background secondary

flux

Low energy range

AMS Challenges

Primary CR Positron from Dark Matter

Total Flux High Energy

Antiproton High Energy Signal from

KK particle

Light LZP provides measurable fluxes

for AMS-02

SUSY Wino, Little Higgs, KK Theory, PBH, Singlet Scalar, Minimal DM, Technicolor…

With e+, antiproton and

low energy antideuteron we can probe

An example:Antideuteron flux from neutralino, KK Photon and right-

handed neutrino LZP

We have 1 year data @ CNAF = 15 billions particles =

a lot of fun!Kinetic Energy (GeV)

Censorship!

Which DM candidate?

Table - DM Candidates properties

Light candidates GHP: most relevant

HS: Hidden Sector

Scalar, vector, Dirac fermion, Majorana fermion, Rarita-Schwinger fermion

Wrong relics

Also leptophilic models may produce antip by EW corrections

A bit of detergent

Neutron Electric Dipole Moment

Theta is a new particle field

Pseudo Nambu-Goldstone Boson of the PQSB: its vev

remove the anomaly, through a potential minimum

QCD Instanton Sector

Kinetic term From Goldstone Theorem:

EM Anomaly

Maxwell-Chern-Simons Equations

Light shining through walls experiments

Currents

From CDM to BEC

a

a

a

a

Axions rethermalize and reach TBEC

Galactic Halos: Tidal Torque Theory

v 0

v 0

Conclusions• Dark Matter is the simplest and most clever way to deal with astrophysical and cosmological problems: DM has to exist!• Exotics candidates• SUSY candidates• SUSY antagonist• We prefer: minimal scalar and Majorana-like solution, from a strong or EW Simmetry Breaking• AMS will soon demonstrate the presence or absence of WIMPs annihilation products