ASTROPARTICLE PHYSICS in SWEDENASTROPARTICLE PHYSICS in SWEDENexperimentsexperiments

• Stockholm univ., Royal Inst. of Technology (KTH), Uppsala univ., Kalmar univ.• 15 post-PhD researchers + 12 PhD students + 2 engineers• externally financed by

- Swedish Research Council (SRC/VR) investments, salaries, run. costs- Knut and Alice Wallenberg Foundation (KAW) investments- Swedish National Space Board (SNSB) investments, salaries, run. costs- Swedish Polar Research Secretariat drillers at the South Pole

• large international collaborations• started in ~1990

Olga Botner, UppsalaECFA meeting, May 9, 2008

Scientific ScopeScientific Scope• knowledge of the Universe from

- studying photons- charged particles (CRs)

• what are the sources of the CRs at the highest energies ?

• how are these particles accelerated ?

• violent processes in the vicinity of black holes?

Gamma Ray BurstsActive Galactic Nuclei

COMMON SCIENTIFIC THEME IUnderstanding processes

generating immense energy outflows in the Universe.

COMMON SCIENTIFIC THEME IUnderstanding processes

generating immense energy outflows in the Universe.

PAMELA, IceCube+IceTopPAMELA, IceCube+IceTopGLAST, PoGoLiteGLAST, PoGoLite

• can we learn more from ’s?IceCubeIceCube

Scientific scopeScientific scope

COMMON SCIENTIFIC THEME IIInvestigation of the possible particle composition of DM.

COMMON SCIENTIFIC THEME IIInvestigation of the possible particle composition of DM.

• WIMPs in extensions of the SM- masses order of GeV – TeV- couplings on the EW scale

• could have been thermally produced in the early Universe• give the required relic density without fine-tuning• candidates

- the neutralino a favourite - the lightest Kaluza-Klein state- the inert Higgs

IceCube, PAMELA, GLASTIceCube, PAMELA, GLAST

p

cosmic accelerator

Atmospheric neutrinos are isotropic

Atmospheric muons come from above

CMB

we believe• that sources producing CRs also produce ’s

• ’s propagate through space with little hindrance and point back to their sources

Neutrino Observations with IceCubeNeutrino Observations with IceCube

IceTop

InIce

air shower detector

threshold ~ 300 TeV 80 stations with 320 digital OMs

80 strings 4800 digital OMs 17 m between DOMs 125 m between strings

2004-2005 : 1 String

2005-2006: 8 Strings

AMANDA 19 strings 677 OMs

2006-2007: 13 Strings

2007-2008: 18 strings

complete 2011

Science menu

• UHE ’s• cosmogenic ’s• supernova ’s• dark matter• exotica ex. monopoles, Q-balls …

Detection principleDetection principle

10” Hamamatsu PMT self-contained, reconfigurable digital DAQ system timing resolution < 2 ns robust, low failure rate (1 %) about 20% of all DOMs are assembled and quality tested in Stockholm and Uppsala

Digital Optical Module

Status of AMANDA/IceCubeStatus of AMANDA/IceCube

• AMANDA proof of concept

• final configuration 2000 taking data, now integral part of IceCube

• almost all relevant limits on cosmic fluxes below 1018 eV are from AMANDA

• AMANDA proof of concept

• final configuration 2000 taking data, now integral part of IceCube

• almost all relevant limits on cosmic fluxes below 1018 eV are from AMANDA

• IceCube deployed successfully now 50% complete - 1 string (2005)+8 strings (2006) + 13 strings (2007) + 18 strings (2008)

• installed strings are immediately operational

• mainly funded through an MRE grant from the NSF 242.1 MUSD - and Sweden, Belgium, Germany 34.5 MUSD

• int’l collaboration: USA (12 inst)+Europe (15 inst)+Japan+New Zealand

• from Sweden: Stockholm univ., Uppsala univ.

• first analyses already published• analysis techniques are continually refined as we gain operational knowledge improved analysis sensitivity

• IceCube deployed successfully now 50% complete - 1 string (2005)+8 strings (2006) + 13 strings (2007) + 18 strings (2008)

• installed strings are immediately operational

• mainly funded through an MRE grant from the NSF 242.1 MUSD - and Sweden, Belgium, Germany 34.5 MUSD

• int’l collaboration: USA (12 inst)+Europe (15 inst)+Japan+New Zealand

• from Sweden: Stockholm univ., Uppsala univ.

• first analyses already published• analysis techniques are continually refined as we gain operational knowledge improved analysis sensitivity

AMANDA – examplesAMANDA – examples

use the Earth as a filter to remove atmospheric ’s

4282 ’spredominantly atmospheric

map of Northern sky

Point source searches 2000 - 2004

Off-Source

On-Source

cc ,bb ,tt , ,W,Z 0,HH 0

HZW

ll

qq

,,

~~

WIMP search

Swedish groups in AMANDA/IceCubeSwedish groups in AMANDA/IceCube

• thanks to early support from SRC, KAW and the Swedish Polar Research substantial contribution to the investment costs and development large impact and influence

• 1st spokesperson for the IceCube collaboration• seat on the executive committee (1/9)• leading role in analysis coord., simulation coord., WIMP wg• speakers committee, publication committee

• h/w development for AMANDA – trigger, amplifiers, OMs• assembly and quality tests of DOMs for IceCube (~ 900)• drillers, one winter-over• physics analysis : WIMPs, UHE ’s, search, (GRB)• ice model, geometry calibration with downgoing ’s

• 8 post-PhD researchers + 5 PhD students

• in the center of IceCube• below 1750 m (excellent ice)

• full year observation of the Sun• sources in the direction of the galactic center• low energy threshold

Extensions of IceCubeExtensions of IceCube

UHE:UHE:• radio• acoustics• radio• acoustics

• an active volume of IceCube x 100• Sweden takes part in the acoustics R&D

• 6 densely instrumented strings• funds granted by KAW 2007

- assess South Pole ice properties - develop hardware

Low energy Deep Core ext.Low energy Deep Core ext.

km

km

• a satellite based powerful charged particle identifier• launched June 15, 2006 from Baikonur, Kazakhstan• elliptical orbit: altitude 350 – 610 km, inclination 70• continuous data-taking > 600 days

>109 triggers recorded and under analysis• int’l collaboration: Italy (7 inst) + Russia (3 inst) + Germany + Sweden• from Sweden: KTH (3 post-PhD researchers + 3 PhD students)

Scientific goalsScientific goals

• search for dark matter annihilation• search for anti-helium (primordial antimatter)• study of cosmic-ray propagation

- light nuclei and isotopes• study of electron spectrum (local sources?)• study solar physics and solar modulation• study terrestrial magnetosphere

Anticoincidence reduces out of acceptance background

Sign of charge, rigidity, dE/dx

Electron energy, dE/dx, lepton-hadron

separation

e- p _

e+ p (He,...)

Trigger, ToF, dE/dx

- +

~470 kg

~360 W

~1.

3 m

21.5 cm2sr

Si-W

0.45 T magnet + silicon tracker

Sweden’s contribution

Energy range Particles/3 years

Antiproton flux 80 MeV - 190 GeV O(104)Positron flux 50 MeV – 270 GeV O(105) Electron/positron flux up to 2 TeV (from calorimeter)

Electron flux up to 400 GeV O(106)Proton flux up to 700 GeV O(108)

Light nuclei (up to Z=6) up to 200 GeV/n He/Be/C: O(107/4/5)

Antinuclei search Sensitivity of O(10-8) in He-bar/He

1 HEAT-PBAR flight ~ 22.4 days PAMELA data1 CAPRICE98 flight ~ 3.9 days PAMELA data

Design performanceDesign performance

• unprecedented statistics and new energy range for CR physics e.g. contemporary antiproton & positron energy, Emax 50 GeV• simultaneous measurements of many species

• constrain secondary production models

Secondary production

Primary production

annihilation m() = 964 GeV

Secondary production (CAPRICE94-based)

Secondary production ‘C94 model’ + primary

distortion

Secondary productionMoskalenko&Strong

Secondary production

Secondary production ‘M+S model’ + primary distortion

Primary production

annihilation m() = 336 GeV

anti-protonsanti-protonspositronspositrons

1. Simon et al., ApJ 499 (1998) 2502. Ullio , astro-ph/99040863. Bergström et al., ApJ 526 (1999) 215

4. Moskalenko &Strong, ApJ 493 (1998) 6945. Protheroe, ApJ 254 (1982) 3916. Baltz&Edsjö, Phys Rev D59 (1999) 023511

pppppp ISMCR

ee

epp ISMCR

0

backgrounds:

Antiproton / proton flux ratio

Preliminary

• order of magnitude more data that all previous measurements • significant new data at high energies

PAMELA summaryPAMELA summary• PAMELA has been in orbit and studying charged cosmic rays for almost 2 years (3 year nominal mission)

• Sweden participates in the governing bodies of Pamela

• PAMELA is routinely collecting data, ~109 triggers have been registered to date, and ~15 GB of data is down-linked per day

• results on antiproton to proton flux ratio (2 – ~80 GeV) are being prepared for PRL; future publications will cover lower and higher energies (>~ 50 MeV and <~200 GeV )

• results on positron fraction to follow shortly

• many other results also in preparation (cosmic ray electrons, nuclei, search for antihelium, solar flares, radiation belts, …)

• A new era in space-based cosmic-ray physics!

The Gamma-ray The Gamma-ray Large Area Space Large Area Space

TelescopeTelescope

• satellite based -ray detector• low Earth circular orbit: altitude 550 km, inclination 26• operational goal: > 5 years• 2 instruments

- Large Area Telescope (LAT) sensitivity range 20 MeV – 300 GeV- Gamma-ray Burst Monitor (GBM)

• main science goals: • search for evidence of DM annihilation• high energy behaviour of GRBs and transients

• int’l collaboration: USA (8 inst)+France (4 inst)+Italy (6 inst) +Japan (2inst)+Sweden (3 inst)• Sweden: Stockholm u., KTH, Kalmar (4 post-PhD researchers + 2 PhD-students)

GLASTGLAST

Overview of Large Area TelescopePrecision Si-strip Tracker

- measure the direction- gamma ID

Segmented Anticoincidence detector- reject background of charged

cosmic rays

Hodoscopic CsI(Tl) calorimeter - measure the energy- image the shower

~180 cm

~12

0 cm

e–

TKR High aspect ratio =Small FOVCAL

TKRCAL

Low aspect ratio =Large FOV

3000 kg

e+

Swedish contributions

• the full set (>1500) CsI crystals for the calorimeter (1999)

• testing and qualification of the crystals

Swedish contributions

• the full set (>1500) CsI crystals for the calorimeter (1999)

• testing and qualification of the crystals

Sweden in GLASTSweden in GLAST

• physics interest focuses on DM searches• prime candidates SUSY , UED, inert Higgs• sources

• galactic centre• galactic halo• galactic satellites/ dwarf galaxies• extra-galactic diffuse • ”smoking gun” DM annihilation into or Z

• backgrounds• CR induced diffuse galactic -rays• extra-galactic diffuse -rays (superposed AGN)• charged particles

• leading role in Dark Matter working group• active role in GRB working group• multi-wavelength observations of AGN • participation in instrument analysis and beam test• participation in governing bodies of GLAST

• leading role in Dark Matter working group• active role in GRB working group• multi-wavelength observations of AGN • participation in instrument analysis and beam test• participation in governing bodies of GLAST

MC 5 signal at 200 GeV

GLAST StatusGLAST Status• integration and environmental tests complete (no failures, no performance changes)

• flight software updates and • thermal-vacuum tests completed

The LAT is at Cape Canaveral, Florida.

COMPARISON WITH EGRETField of View factor ~ 4 Point Spread function factor > 3 Effective area factor > 5

A factor > 30 improvement in sensitivity below < 10 GeV, and >100 at higher

energies.

COMPARISON WITH EGRETField of View factor ~ 4 Point Spread function factor > 3 Effective area factor > 5

A factor > 30 improvement in sensitivity below < 10 GeV, and >100 at higher

energies.

expected launch: 2008

e.g. G L A S T

trE ,ˆ,

PtrE ˆ,,ˆ,

[10 keV – 300 GeV]

[25 – ~80 keV]

• photons can be characterised by their energy, direction, time of detection and polarisation

• polarisation never exploited at these energies

• measuring the polarisation of gamma-rays provides a powerful diagnostic for source emission mechanisms

• polarisation can occur through scattering / synchrotron processes, interactions with a strong magnetic field

sensitive to the ‘history’ of the photon

SLAC / KIPAC, Hawaii

KTH, Stockholm University

Tokyo Institute of Technology, Hiroshima University, ISAS.

PoGOLite payloadPoGOLite payload

PoGOLite SummaryPoGOLite Summary

• PoGOLite stands to open a new observation window on sources such as rotation-powered pulsars and accreting black holes through a measurement of the polarisation of soft gamma rays (25 - ~80 keV).

• KTH chairs the collaboration

• Sweden (KTH Physics and SU Astronomy) contribute with the anticoincidence system, polarimeter construction, attitude control system and lead the pathfinder flight campaign.

• A prototype detector has been tested with polarised photon, proton, and neutron beams and the design and simulation validated.

• Construction of flight hardware is currently in progress in Stockholm

• Pathfinder balloon flight from Esrange, northern Sweden, 2010.

Extra material

Hot-water drilling

Hose reel Drill tower

IceTop tanks5 MW Hot water generator

Measurements:►in-situ light sources►atmospheric muons

Average optical ice parameters:

abs ~ 110 m @ 400 nmsca ~ 20 m @ 400 nm

Scattering Absorption

bubbles

dust

dust

ice

Detector medium: ice to meet you

Proposed : 91 holes, 1 km spacing 5 radio+3 acoustic sensors/hole

note the scale!radio

acousticparticle shower heating suddenthermal expansion acoustic pulse

both methods in exploratory phase: - assess South Pole ice properties - develop hardware

to catch ’s at the highest energies… listen

particle shower moving charge excess radio pulse

sudden energy deposit of ~109 GeV

Expected rates from astrophysical sources per square km

Diffuse• GZK: 1/year?• Diffuse GRB: 20/year (Waxman)• Diffuse AGN: few >100/year (Mannheim)

Point like:•GRB (030329): 1-10/burst (Waxman)•AGN (3C279): few/year (Dermer)•Galactic SNR (Crab): few/year? (Protheroe)•Galactic microquasars: 1-100/year (Distefano)

AntiprotonsAntiprotons

Secondary production (upper and lower limits)

Simon et al. ApJ 499 (1998) 250.

Secondary production

(CAPRICE94-based)Bergström et al. ApJ

526 (1999) 215

Primary production from annihilation (m() = 964 GeV)

Secondary production ‘C94 model’ +

primary distortion

PAMELA

Ullio : astro-ph/9904086

PositronsPositrons

Secondary production ‘Leaky box model’ R. Protheroe, ApJ 254 (1982) 391.

Secondary production ‘Moskalenko + Strong model’ without reacceleration. ApJ 493 (1998) 694.

Primary production from annihilation (m() = 336 GeV)

Secondary production ‘M+S model’ +

primary distortion

PAMELA

Baltz + Edsjö, Phys Rev D59 (1999) 023511.

84 GV interacting antiproton

candidate

92 GV positron candidate

GLAST Sweden

Sweden provided the full set of CsI crystals for the calorimeter (1999), subsequently testing and qualification of the crystals. (Wallenberg foundation: 20 MSEK)

Today: Leading role in Dark Matter working groupActive role in GRB working groupMulti-wavelength observations of AGN Partipation in instrument analysis and beam testParticipation in governing bodies of GLAST

Funding: (inkl. overhead)

Swedish Space Board: 1.1 MSEK (2007), 1.0 MSEK (2008) (increase expected post-launch)Swedish Space Board: 1.2 MSEK (2007-2009) (50 % Researcher Position, assoc. prof level)Swedish Science Council: 1.1 MSEK (2006-2009) (50 % Researcher Position, assist. prof. Level).

Personell:Permanent: 0.25 FTE Prof. (all male) 0.75 FTE Assoc. Prof (all male) (all active in Astroparticle Physics, 100%)

Non-permanent:0.9 FTE Assist. Prof. (all male)2 FTE PostDoc (all female)1.8 FTE PhD students (all male)0.25 Technical personell (all male) (all active in Astroparticle Physics, 100%)

• •

Crab nebula, 1054

Compton scatteringCompton scattering

10

0 k

eV

10

ke

V

Compton scatter

Photoelectric absorption

• Incident deposits little energy at Compton site

• ‘Large’ energy deposited at photoelectric absorption site

• large energy difference

• Can be distinguished by simple plastic scintillators (despite intrinsic poor energy resolution)

Array of plastic scintillators

Measuring polarisationMeasuring polarisation

Compton scattering: Klein-Nishina formula0 when =90o

Max when =90o

• from a polarised source undergo Compton scattering in a suitable detector material

• Higher probability of being scattered perpendicular to the electric field vector (polarisation direction)

• Observed azimuthal scattering angles are therefore modulated by polarisation

Azimuthal scatteringangle,

Polarisation plane

Polarscatteringangle,

kk0

E

PoGOLite instrument schematicPoGOLite instrument schematic

Slow Scintillator Hexagonal TubeActive Collimator

Fast ScintillatorDetector Section

PMT Assembly

BGO BottomVeto

60cm20cm

19cm4.0cm

0.9cm overlap

[NB: simplified! 217 wells in reality]

BGO anticoincidence

BGO

BGO

Crab Pulsar emission modelsCrab Pulsar emission models

[Polar cap] [Slot gap caustic] [Outer gap]

Testing emission models with PoGOLiteTesting emission models with PoGOLite(OSO-8 assumed)

Polar cap

Slot gap caustic

Outer gap

Maiden flight: 2010Maiden flight: 2010

• Reduced volume ‘pathfinder’ flight planned from Esrange facility in North of Sweden.

• 6 – 24 hour long flight expected

• Assess backgrounds, study Crab nebula and Cygnus X-1

• Total payload weight ~1000 kg

• 1.11x106 m3 balloon; target altitude ~40 km

Pulsar / SNR

High-mass X-ray binary