1. Cosmic Accelerators Astrophysics with High Energy Particles
Graduiertenkolleg “Physik an Hadronen-Beschleunigern”
Klausurtagung,
Thomas Lohse
Humboldt University Berlin

2. The Cosmic Ray Spectrum Discovery Balloon Flight Victor Hess, 1912
solar modulation
E2.7, mostly protons
Knee
transition to
heavier nuclei
E3.1
mostly Fe?
Discovery Balloon Flight Victor Hess, 1912
Ankle
Power Laws
Shock Acceleration
predicts FSource  E2
transition to
lighter nuclei ? ?
Direct Measurements
EAS Detectors

3. Open questions after 90 years
What and where are the sources?
How do they work?
Are the particles really accelerated?...
…or due to new physics at large mass scales?
And how do cosmic rays manage to reach us?

4. Production in Cosmic Accelerators  0  e 
Inverse Compton
(+Bremsstr.)
protons/nuclei
electrons/positrons
radiation fields and matter

5. Experimental Techniques ( E  10 GeV )
Primary (Hadron,Gamma)
Air Shower
Experimental Techniques ( E  10 GeV ) 
Atmospheric  (4) 
Fluorescence Detector
Fluorescence Č
Hadron-Detector
Č-Telescope
R&D
Radio-Detection
Acoustic-Detection
Scintillator or Water Č 
InstrumentedWater / Ice
Primary  (4)
, e, 

6. Outline Outline Cosmic rays beyond the ankle
Neutrinos from cosmic ray sources
Gammas from cosmic ray sources
Outline
Outline
Cosmic rays beyond the ankle
Neutrinos from cosmic ray sources
Gammas from cosmic ray sources

7. Greisen-Zatsepin-Kuzmin Cut-Off:
Energy loss in cosmic microwave background (CMB)
p(100 EeV) + (CMB)  p + , n + 
p(100 EeV) p  
p beyond ankle
E  eV
1020
1019
1018
E3FE
cut-off
reprocessed p
p below ankle
 isotropized in B-fields

8. AGASA: surface detector array HIRes: fluorescence light detector
model fit to HIRes data
AGASA
HIRes
Fly’s Eye
no GZK cut-off?
AGASA
triplet
AGASA: surface detector array
HIRes: fluorescence light detector
Spectra consistent allowing for 30% systematic energy shift…

9. The Pierre Auger Project
3000 km2 Hybrid Detector
4 Fluorescence Sites
AGASA
1600 Water Č-Detectors
 75% installed

10. Energy Calibration of Surface Detectors
Clean EeV Hybrid Events
contemporaneous atmospheric monitoring
statistically limited up to now…
14% duty cycle
Present systematics:
Calibration 12%
Fluorescence yield 15%
calorimetric measurement
 independent of primary composition
 independent of air shower details

11. First Look at  3 EeV Energy Spectrum
( from surface detector array )
Data: Jan – Jan 2005
Exposure: 1750 km2 sr yr
 AGASA + 7%
Events: 3525
Power Law Fit
systematic errors

12. preliminary Calibration uncertainty
AUGER best fit
preliminary Calibration uncertainty

13. Search for Localized Excess Fluxes with AUGER
Exposure Map
Example:
1 EeV  E  5 EeV
5 Smoothing
Event Map
Excess significance distribution
30548 events
AGASA evidence for small scale anisotropies NOT confirmed!

14. AUGER Search for Individual Targets: No Signals
AGASA / SUGAR excesses close to galactic centre NOT confirmed (with larger statistics)
AGASA ( 1018 eV )
4.5 
20
SUGAR (  eV )
2.9 
5.5

15. Cosmic rays beyond the ankle
Neutrinos from cosmic ray sources
Gammas from cosmic ray sources

16. The Main Players presently: Amanda / IceCube, South Pole Ice
BAIKAL, Water of Lake Baikal
+ future Mediterranean detectors
IceCube
(in construction)
South Pole
Dome
AMANDA
Summer camp
1500 m
Amundsen-Scott South Pole Station
2000 m
[not to scale]

17. Search for Diffuse Cosmic Neutrinos
upward  (2 coverage)
preliminary
horizontal
vertical
atmospheric 
AMANDA
1: B10, 97, ↑μ
2: A-II, 2000, unfold.
3: A-II, 2000, casc.
4: B10, 97, UHE
Baikal
5: 98-03, casc.
1:1:1 flavour flux ratio
all-flavour limits
IceCube 3 years
E2-Flux Limit
 add directional & temporal constraints …

18. Point Source Search in Northern Hemisphere
  90
90
test region (MC-optimized)
background estimation from real data
AMANDA preliminary
Selected: clean 
Expected: 3438 atmosph. 
Hemisphere averaged
33 pre-selected point-source candidates
Source stacking (11 samples)
Typical limits
No significant excess

19. Unbinned Search for Clusters
  90
90
Significance Sky Map
Maximum Excess  3.4 
max. excess from random skymaps
3.4 
 92%
AMANDA preliminary

20. … AMANDA Search for Transient Sources time window: 40 / 20 days
events
time
sliding window
time window: 40 / 20 days
angular bin: 2.25°-3.75°
fixed a priori
12 Objects tested (over 4 years), no triplets found … BUT …
Source
 Events
 Backgr.
window
 doublets
Prob.
Markarian 421 6
5.58
40 days
Close to 1
1ES 5
3.71 1
0.34
3EG J
4.37
0.43
QSO
5.04
0.52
Cygnus X-3
20 days
GRS
4.76
0.32
GRO J
5.12 …

21. AMANDA – 1ES1959+650 – 2.25o search bin size
revisited a posteriori
The first cosmic ray neutrino ???
5 events
background
dublet window
66 day triplet
WHIPPLE E > 0.6 TeV
HEGRA
E > 2 TeV
Orphan -flare (not seen in X-rays)
Statistical significance hard to tell … but promising!
Lessons learned: Multimessenger & multiwavelength studies important. Use -ray flares (not only X-rays)…

22. Cosmic rays beyond the ankle
Neutrinos from cosmic ray sources
Gammas from cosmic ray sources

23. Cherenkov Telescopes (3rd Generation)
H.E.S.S.
CANGAROO III
MAGIC
Veritas
in construction

24. 3.1. Supernovae

25. The Standard Candle for TeV -Astronomy
Crab Supernova a.D. d = 2 kpc
But what about hadrons (protons and nuclei)?
optical
1 lightyear
Synchrotron radiation
Pulsar Wind Nebula:
Electron wind from central pulsar heats the cloud

26. Cassiopaeia A Supernova 1658 a.D. d = 2,8 kpc
X ray picture
“Shell Type” SNR:
no electron wind from pulsar
gamma signal from shell regions not totally drowned in that of electron wind
good source class to observe hadron acceleration

27. First Resolved Supernova Shells in -Rays
resolution
H.E.S.S. 2004
E  210 GeV
RX J1713.73946
resolution
H.E.S.S. 2004
E  210 GeV
RX J1713.73946
RX J0852.04622
H.E.S.S. 2005
E  500 GeV
Strong correlation with X-ray intensities
SN-Shells are accelerating particles up to at least 100 TeV!
But are these particles protons/nuclei or electrons?

28. Electron or Hadron Accelerator?
radio infrared visible light X-rays VHE -rays
Matter Density
Stars B
Ee
Cosmic
Proton
Accelerators
CMB
Dust
Cosmic
Electron
Accelerators
E2 dN/dE B
Ee
Synchrotron Radiation
Inverse Compton
0
Synchrotron Radiation of Secondary Electrons
log(E)

29. Electron accelerator fits for RX J1713.73946 :
Continuous electron injection over 1000 years
Injection spectrum: power law with cutoff
H.E.S.S.
EGRET
  2.0
B  7, 9, 11 G
B  10 G
  2.0, 2.25, 2.5
large  & injection rate  bremsstrahlung important
needs tuning at low E
IC peak not well described
B-field low for SNR shell

30. Spatially resolved spectra of RX J1713.73946
TeV photon index  const
H.E.S.S.
preliminary
G. Cassam-Chenaï A&A 427, 199 (2004)
X-ray photon index
TeV / X-ray intensities correlate, but NOT the spectral shapes
 very hard to understand for pure electron accelerator !

31. Proton accelerator fit:
H.E.S.S.
RX J1713.73946
Continuous proton injection over 1000 years
Injection spectrum: power law, index 2
Different cutoff shapes & diffusion parameters

32. 3.2. Inner Glactic Plane
30 ≲ l ≲ 30
3 ≲ b ≲ 3

33. H.E.S.S. Scan of Inner Galactic Plane
5  SNR
3  Pulsar
 3  ???
14 new sources, all extended! Possible counterparts:
(plus previously known ones)
HESS J1837069
HESS J1834087
HESS J1825137
HESS J1813178
HESS J1804216
G0.90.1
HESS J1747281
Galactic Centre
HESS J1745290
HESS J1713381
RX J1713.73946
HESS J1708410
HESS J1702420
HESS J1640465
HESS J1634472
HESS J1632478
HESS J1616508
HESS J1614518
HESS J
HESS J
HESS J
Resolution

34. … a new source class: “Dark Accelerators”
extended
hard spectra,   
steady emission
TeV-Gamma-Ray
Radio
X-Ray
Five sources known: TeV J2032 (HEGRA)
HESS J1303631 HESS J1614518
HESS J1702420 HESS J1708410
What are these sources? Are they hadron accelerators?

35. 3.3. Galactic Centre HESS J1837069 HESS J1834087 HESS J1825137
RX J1713.73946
HESS J1708410
HESS J1702420
HESS J1640465
HESS J1634472
HESS J1632478
HESS J1616508
HESS J1614518

36. Galactic Centre: A pointlike TeV- source
Chandra GC survey
NASA/UMass/D.Wang et al.
Chandra GC survey
NASA/UMass/D.Wang et al.
CANGAROO (80%)
CANGAROO (80%)
H.E.S.S.
H.E.S.S. (95%); MAGIC similar
Whipple
(95%)
Whipple
(95%)
H.E.S.S.
Systematic
pointing error
Radio Contour
Radio
Sgr A East
SNR
Contours from Hooper et al. 2004
Astrophysical Source Candidates:
3106 M⊙ black hole Sgr A
EMF close to rotating black hole
Accretion shocks
Supernova Remnant Sgr A East
Expanding shock waves
Sgr A*

37. … or maybe dark matter annihilation ?
Crab GC
MAGIC
H.E.S.S.
no visible cut-off  rather large mass
measured flux  large cross-section and/or DM density
20 TeV Neutralino
20 TeV Kaluza Klein particle
… unlikely !

38. Galactic Centre Neighbourhood
SNR G0.90.1
HESS J1747281
Galactic Centre
HESS J1745290
EGRET GeV--sources
~150 pc

39. molecular clouds density profiles
Galactic Centre Neighbourhood
...point sources subtracted
first resolved detection of diffuse TeV--radiation
cosmic rays (hadrons) interacting with molecular clouds
Molekuelwolken
molecular clouds density profiles
HESS J1745290
~150 pc

40. Cosmic Ray Spectrum at the GC...
is very different from the one at earth
diffuse
radiation
expected flux for CR spectrum observed on earth
Cosmic rays are much harder and have 3 larger density around the GC
Possible reason:
Close-by source population
Possibly single SN-explosion

41. 3.3. Active Galaxies

42. Blazars General Active Galactic Nuclei (AGN):
Supermassive black holes, M  109 M
accretion disk and relativistic jets
Blazar-Typ: Jet points towards the earth
Doppler-boost  TeV -radiation

43. Absorption in (infrared) extragalactic background light (EBL)
(TeV) + (EBL)  e+e- e+ e-   E
dN/dE E
dN/dE
Physics of compact objects,
acceleration/absorption in jets,…
Measurement of EBL (  Cosmology )

44. Cut-off Energy and -Ray Horizon
PG 1553113

45. EBL Unfolding of Measured Spectra
Too much
EBL
EBL
Hardest plausible
source spectrum
 = 1.5
1 ES 1101
 = 2.9±0.2
H 2356 (x0.1)
 = 3.1±0.2
H 2356 (x 0.1)
G = 3.1±0.2
Preliminary

46. New Upper Bound on EBL Density
EBL density seems  2  smaller than expected! Little room for EBL sources other than galaxies (early stars…)
excluded by H.E.S.S.
Direct IRTS
Measurements
Upper Limits
Assumed shape for rescaling
Lower Limits
(Galaxy Counts)
H.E.S.S. upper bound
from spectral shapes of
1ES (z = 0.186)
H (z = 0.165)

47. Summary
Cosmic ray puzzle persists…but is under pressure by massive attack from EAS-arrays, - and -telescopes
Progress in understanding knee, ankle and GZK-region AUGER data disfavour small scale anisotropies
Cosmic -detection in multi-messenger campaigns ?
Neutrino astronomy might start sooner than expected !
Major break-through in TeV--astronomy
supernova shells are  100 TeV accelerators
large population of extended galactic TeV sources discovered
first microquasar-candidates established as TeV accelerator
diffuse galactic TeV emission (Milagro, H.E.S.S.)
TeV- from Active Galactic Nuclei at large red-shifts, …

48. The Cosmic Accelerator Cocktail ?
Pulsars
Supernovae
AGN
Dark Accelerators
The Cosmic Accelerator Cocktail ?
Gamma Ray Bursts
Black Holes
Microquasars