Date post: | 29-Jan-2016 |
Category: |
Documents |
Upload: | merryl-oneal |
View: | 214 times |
Download: | 0 times |
Cosmic RaysGammas, Hadrons, Neutrinos
Thomas LohseHumboldt University Berlin
HEP2005 International Europhysics Conference on High Energy Physics
July 27th 2005Lisboa, Portugal
The Cosmic Ray Spectrum
Power Laws
Shock Accelerationpredicts FSource E2
Discovery Balloon Flight Victor Hess, 1912
sola
r m
odul
atio
n
E2.7, mostly protons
transition toheavier nuclei E3.1
mostly Fe?
Knee
?
Ankle
EAS DetectorsDirect Measurements
transition tolighter nuclei ?
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?
Production in Cosmic Accelerators
protons/nucleielectrons/positrons
p
0
radiation fields and matter
p
e Inverse Compton(+Bremsstr.)
Experimental Techniques ( E 10 GeV )
InstrumentedWater / Ice
Scintillator or Water Č
Č-Telescope
Č
Fluorescence Detector
Hadron-Detector
Fluorescence
Primary (Hadron,Gamma)
Air Shower
Atmospheric (4)
Primary (4)
, e,
R&DRadio-Detection
Acoustic-Detection
Outline
1. The nature of the knee
2. Cosmic rays beyond the ankle
3. Neutrinos from cosmic ray sources
4. Gammas from cosmic ray sources
1. The nature of the knee
2. Cosmic rays beyond the ankle
3. Neutrinos from cosmic ray sources
4. Gammas from cosmic ray sources
Outline
log E
log
E
2.5
F
pSi
Fe
Knee
Interpretation of the Knee
EKnee ZEKnee Z
New physics in air shower development
new strong interaction
new strong interaction
EKnee AEKnee A
Diffusive escape from galactic B-field
Maximum acceleration energy
KASCADE: Unfolding for individual mass groups
Input:
measured ne vs. n
hadronic interaction models
• large model dependence
• no model describes all data
• more experimental input for hadronic interaction models needed
1. The nature of the knee
2. Cosmic rays beyond the ankle
3. Neutrinos from cosmic ray sources
4. Gammas from cosmic ray sources
p beyond ankle
Greisen-Zatsepin-Kuzmin Cut-Off:Energy loss in cosmic microwave
background (CMB)p(100 EeV) + (CMB) p + , n +
p(100 EeV)p
p below ankle isotropized in B-fields
E eV102010191018
E3
FE
cut-off
reprocessed p
no GZK cut-off?
triplet
model fit to HIRes data
AGASA
HIResFly’s Eye
AGASA
AGASA: surface detector array
HIRes: fluorescence light detector
Spectra consistent allowing for 30% systematic energy shift…
The Pierre Auger Project3000 km2 Hybrid Detector
1600 Water Č-Detectors 50% installed
4 Fluorescence Sites3 fully operational
AGASA
Energy Calibration of Surface Detectors
14% duty cycle
Present Systematics:Calibration 12%Fluorescence yield 15%
Clean EeV Hybrid Events
contemporaneous atmospheric monitoring
statistically limited
up to now…statistically limited
up to now…
• calorimetric measurement independent of primary
composition independent of air shower details
First Look at 3 EeV Energy Spectrum( from surface detector array )
Data: Jan. 2004 – Jan 2005
Exposure: 1750 km2 sr yr AGASA + 7%
Events: 3525
Power Law Fit
2.4d.o.fχ
EEd
Id
2
03.084.2
systematic errors
AUGER best fit
preliminary Calibration uncertainty
Search for Localized Excess Fluxes with AUGER
Exposure Map
Event Map
Example:1 EeV E 5 EeV5 Smoothing
30548 events
AGASA evidence for small scale anisotropies NOT confirmed!
Excess significance distribution
1. The nature of the knee
2. Cosmic rays beyond the ankle
3. Neutrinos from cosmic ray sources
4. Gammas from cosmic ray sources
Amundsen-Scott South Pole Station
South PoleDome
Summer camp
AMANDA
1500 m
2000 m[not to scale]
IceCube(in construction)
The Main Players presently: • Amanda / IceCube, South Pole Ice• BAIKAL, Water of Lake Baikal
+ future Mediterranean detectors
upward (2 coverage)
preliminarypreliminary
horizontal
vertical
atmospheric
Search for Diffuse Cosmic Neutrinos
1:1:1 flavour flux ratio
E2-Flux Limit
add directional & temporal constraints …
IceCube 3 years
h24 h
90
90
Point Source Search in Northern Hemisphere
test region (MC-optimised)
background estimation from
real data
AMANDA 2000-2003
preliminary
AMANDA 2000-2003
preliminary
Selected: 3329 clean
Expected: 3438 atmosph.
Selected: 3329 clean
Expected: 3438 atmosph.
• Hemisphere averaged• 33 pre-selected point-source candidates• Source stacking (11 samples)
Typical limits
No significant excess
.l.c %90scm10GeV 10 1298ν
h24 h
90
90
Unbinned Search for Clusters
AMANDA 2000-2003
preliminary
AMANDA 2000-2003
preliminary
Significance Sky Map
Maximum Excess 3.4
max. excess from random
skymaps3.4
92%
AMANDA Search for Transient Sources
events
time
sliding window • time window: 40 / 20 days• angular bin: 2.25°-3.75°
fixed a priori
Source Events Backgr. window doublets Prob.
Markarian 421 6 5.58 40 days 0 Close to 1
1ES1959+650 5 3.71 40 days 1 0.34
3EG J1227+4302 6 4.37 40 days 1 0.43
QSO 0235+164 6 5.04 40 days 1 0.52
Cygnus X-3 6 5.04 20 days 0 Close to 1
GRS 1915+105 6 4.76 20 days 1 0.32
GRO J0422+32 5 5.12 20 days 0 Close to 1
12 Objects tested (over 4 years), no triplets found … BUT …
…
5 events
backgrounddublet window
66 day triplet
WHIPPLE E > 0.6 TeV
HEGRAE > 2 TeV
AMANDA – 1ES1959+650 – 2.25o search bin sizerevisited a posteriori
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)…
The first cosmic ray neutrino ???
1. The nature of the knee
2. Cosmic rays beyond the ankle
3. Neutrinos from cosmic ray sources
4. Gammas from cosmic ray sources
H.E.S.S. CANGAROO III
MAGIC
Veritas
in construction
Cherenkov Telescopes (3rd Generation)
resolution
H.E.S.S. 2004E 210 GeV
RX J1713.73946
resolution
H.E.S.S. 2004E 210 GeV
RX J1713.73946
1) Supernova Shells: Cosmic Ray Accelerators?
H.E.S.S. 2005 preliminary
preliminary
E 500 GeV
RX J0852.04622
Strong Correlation with X-ray IntensitiesStrong Correlation with X-ray Intensities
• SN-Shells are accelerating particles up to at least 100 TeV!• But are these particles protons/nuclei or electrons?
E2 d
N/d
E
ln(E)
Stars
radio infrared visible light X-rays VHE -rays
CMB
Dust
CosmicElectron
Accelerators BEe
Electron or Hadron Accelerator?
Synchrotron Radiation Inverse Compton
e
e
EdNd
B, e
e
EdNd BEe
Cosmic Proton
Accelerators
, p
p
Ed
Nd Matter Density
0Synchrotron Radiation of Secondary Electrons
EGRET
2.0 2.0
B 7, 9, 11
GB 7, 9, 11
G
Electron accelerator fits for RX J1713.73946 :• Continuous electron injection over 1000 years• Injection spectrum: power law with cutoff
• IC peak not well described• B-field low for SNR shell
• large & injection rate bremsstrahlung important
• needs tuning at low E
αeE
B 10
G B 10
G
2.0, 2.25, 2.5 2.0, 2.25, 2.5H.E.S.S. preliminarymodels: F. AharonianH.E.S.S. preliminarymodels: F. Aharonian
Continuous proton injection over 1000 years Injection spectrum: power law, index 2 Different cutoff shapes & diffusion parameters
Proton accelerator fit:
H.E.S.S. preliminary
RX J1713.73946
models: F. Aharonian
Chandra GC surveyNASA/UMass/D.Wang et al.
CANGAROO (80%)
Whipple
(95%)
H.E.S.S.
Chandra GC surveyNASA/UMass/D.Wang et al.
CANGAROO (80%)
Whipple(95%)
Contours from Hooper et al. 2004
2) Galactic Centre: A TeV- Point Source
H.E.S.S. (95%)
Astrophysical Source Candidates:
• 3106 M⊙ black hole Sgr A
─ EMF close to rotating black hole─ Accretion shocks
• Supernova Remnant Sgr A East─ Expanding shock waves
Radio
H.E.S.S.
Systematicpointing error
Radio Contour
Sgr A*
Sgr A EastSNR
no visible cut-off rather large mass
measured flux large cross-section and/or DM density
… or maybe dark matter annihilation ?
10-13
10-12
10-11
0,1 1 10
E2 F
(E)
[Te
V/c
m2 s]
E [TeV]
20 TeV Neutralino20 TeV Kaluza Klein particle
… unlikely !
H.E.S.S. (preliminary)
3) H.E.S.S. Scan of Inner Galactic Plane
HESS J1834-087
HESS J1804-216
HESS J1640-465
Resolution
8 new sources, all extended! Possible counterparts: 7 SNR/PWN1 ???
TeV-Gamma-RayRadioX-Ray
… a new source class: “Dark Accelerators”
Three sources known: TeV J20324130 (HEGRA)
HESS J1303631
HESS J1616508
What are these sources? Are they hadron accelerators?
• extended• hard spectra, • steady emission
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
4) Extragalactic Sources: Blazars
E
dN/d
E
Measurement of EBL ( Cosmology )
Physics of compact objects,acceleration/absorption in jets,…
EdN
/dE
Absorption in (infrared) extragalactic background light (EBL)
(TeV) + (EBL) e+e-
e+
e-
Cut-off Energy and -Ray Horizon
Mrk421Mrk501
1ES 19596501ES 2344514
PKS 2155304H1426428
PKS 2005489
EBL models
adapted from Blanch & Martinez 2004
more on ICRC‘05
CANGAROO H.E.S.S. VERITAS
MAGIC
5) X-Ray Binary LS 5039: The first TeV Micro-Quasar-Candidate
Accretion from normal star on stellar-mass black hole scaled-down AGN in our Galaxy
• Dynamics of accretion
• Jet production
• Acceleration of electrons vs. hadrons
H.E.S.S.-Discovery in Summer 2004 Galactic Plane Scan:
• 10.5 hours live time spread over 4 months
7 E 0.2 … 4 TeV
• point-like
• steady at 15% c.l.
• hard spectrum 2.12 0.15
Acceleration of particles to ≳ 10 TeV established !
Sciencexpress, July 7th, 2005
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-candidate established as TeV accelerator diffuse galactic TeV emission (Milagro water Č-telescope) TeV- from Active Galactic Nuclei at large red-shifts, …
AGN
Black Holes
Microquasars
Gamma Ray Bursts
Pulsars
Dark Accelerators
Supernovae
The Cosmic Ray Source Cocktail ?