Download - Ul tr a-Hig h En e rg y As tr oP article s
Ultra-High Energy AstroParticles!
Angela V. Olinto
The University of Chicago
ICFA 2008
International Committee for!
Future Accelerators !
Ancient Accelerators! !
Ancient Accelerators! !
from 103 to 109 years old!
Ancient Accelerators! !
from 103 to 109 years old!
Ancient but Powerful!!
! ~ 10 TeV !
! ~ 103 TeV !
Hadrons ~ 108 TeV!!! !
How do they accelerate !
to such high energies?!
We’ll call you as soon as we know!
May take a couple of years…
Beginning to unveil the nature of !the Most Energetic Accelerators in Nature!
A New Era of AstroParticle Physics!
Multimessengers that require Multiple Techniques:
Cosmic Rays: ground arrays, atmospheric fluorescence,
balloons, satellites, space station
HE Gamma-rays: ground arrays, satellites
HE Neutrinos: underground ice and water, balloons, radio
telescopes
A New Era of AstroParticle Physics!Beginning to unveil the nature of !
the Most Energetic Accelerators in Nature!
UHE Cosmic Rays: Pierre Auger South, Telescope Array
HE Gamma-rays: FGST, Milagro, MAGIC, HESS, VERITAS
HE Neutrinos: IceCube, Antares, ANITA
Cosmic Ray!Spectrum!
Non-thermal
Phenomena
Extreme Accelerators
Emax > 1020 eV
Features:
knee, ankle, GZK cutoff
accelerators
propagation
interactions
E-2.7
E-3.1
12 orders of magnitude
32 o
rder
s of
magn
itu
de
RH
IC
Tev
atro
n
LH
C
Ankle
(1 particle /km2 yr)
Ecm = PeV (Euhecr /ZeV)1/2 (2A)1/2
Engel’08
knee
ankle
Each Energy !range tells its story!
108 eV < E < 1011 eV
Solar Modulation
1011eV < E < 1017.5-18.5? eV
Galactic Propagation
1017-18eV < E < 10 20 - 2? eV
Extragalactic Sources
Each Energy !range tells its story!
108 eV < E < 1011 eV
Solar Modulation Barger et al 08
Galactic Accelerators!
E < 1017.5-18.5? eV
Galactic Propagation
Galactic Sources?
Galactic Accelerators!
E < 1017.5-18.5? eV
Galactic Propagation
Galactic Sources?
CREAM
Kascade Grande
IceTop
FGST
ACTs
Galactic Accelerators!
E < 1017.5-18.5? eV
Galactic Propagation
Galactic Sources?
Tycho SN SNR1006
CHANDRA NASA/CXC/SAO
HESS - TeV !’s !!
Hinton, WatsonFest, Leeds
RX J1713 - 20 " Gamma-rays X-rays
CHANDRA
smoking guns of CR acceleration!
see Anders Borgland
R. Dubois
Galactic Accelerators!
E < 1017.5-18.5? eV
Galactic Propagation
Ankle
(1 particle /km2 yr)
Ecm = PeV (Euhecr /ZeV)1/2 (2A)1/2
SNR shock acceleration
in the Galaxy?
HESS SNe
?
Extragalactic Accelerators!
1017-18eV < E < 10 20 - 2? eV
Extragalactic Sources
Extreme Accelerators
Emax > 1020 eV
= 108 TeV!
E-2.7
E-3.1 Ankle
(1 particle /km2 yr)
Ecm = PeV (Euhecr /ZeV)1/2 (2A)1/2
Extragalactic Accelerators?
Extragalactic Accelerators!
Challenging Accelerators!to reach 1020 eV !
LHC magnetic field,"
radius ~ 107 km (Sun – Mercury)!
E = Ze B L!
10% efficiency
1020eV Protons
1020eV Iron
B(G)
L(cm)
E = Ze B L!
10% efficiency
1020eV Protons
1020eV Iron
B(G)
L(cm)
others
GRBs
Galaxy Jets from Black Holes?
Ultra High Energy Cosmic Ray Accelerators?!
Gamma Ray Bursts?
Neutron Stars? Magnetars?
Highest Energies!
E-2.7
E-3.1
RH
IC
Tev
atro
n
LH
C
Ankle
(1 particle /km2 yr)
Ecm = PeV (Euhecr /ZeV)1/2 (2A)1/2
Pointing
Feature
Cosmologically Meaningful Termination !
GZK Cutoff
Greisen, Zatsepin, Kuzmin
1966
p+!cmb" #+ " p + $0
" n + $ +
Proton Horizon
~1020 eV
Chargeless vs Charged!@ Highest Energies!
Photons:
1600s:
G. Galilei
Cosmic Rays
1912: V. Hess
Att
enua
tion
Len
gth!
Lee’95
GZK Feature!
E-2.7
E-3.1 Ankle
(1 particle /km2 yr)
“Cosmologically
Meaningful” Feature
High Resolution Fly’s Eye (1997-2006) 2 fluorescence telescopes!
AGASA (1984-2003) !100 km2 area, !
111 scintillators, 1km spacing !
No GZK cutoff Consistent w/ GZK cutoff
1998
GZK Effect!
# Spectral Feature
+ LSS
# Anisotropies in Sky Distribution
#! Particle* Astronomy!!!
*(electrically charged)
Horizon - observed Protons !
AO, Armengaud, Allard, Kravtsov ‘07
Horizons:!
Gpc
1019 eV ~ 1 Gpc!
1020 eV < 100 Mpc!
100 Mpc
THE SLOAN GREAT WALL
Protons with > 1020.5 eV !
AO, Armengaud, Allard, Kravtsov ‘07
Protons with > 1019.5 eV!
AO, Armengaud, Allard, Kravtsov ‘07
Charged Particle Astronomy !
Window of opportunity
1019 to 1021 eV
Maximize the Statistics in this window
The Pierre Auger Observatory!
HIGH QUALITY
LARGE QUANTITY
Auger South!
1660 tanks in a
3,000 km2
Surface Array
4 Fluorescence
Detector Sites
tanks aligned seen from Los Leones!
4 times 6 telescopes overlooking the site!
Cosmic Ray!
Spectrum!
E-2.7
E-3.1 Ankle
(1 particle /km2 yr)
“Cosmologically
Meaningful” Feature
Energy spectrum from SD showers with $ " 60°!
calib. uncert. 10%
FD syst. unc. 22%
5165 km2 sr yr ~ 0.8 full Auger year
Energy spectrum from SD showers with $ " 60°!
5165 km2 sr yr ~ 0.8 full Auger year
Exp. Obs.
>1019.6 eV 132 ± 9 51
> 1020 eV 30 ± 2.5 2
calib. uncert. 10%
FD syst. unc. 22%
Slope = -2.62 ± 0.03
significance = 6"
ankle
High Resolution !Fly’s Eye!
AGASA !
No GZK cutoff Consistent w/ GZK cutoff
High Resolution !Fly’s Eye!
AGASA !
No GZK cutoff Consistent w/ GZK cutoff
HiRes 2008
High Resolution !Fly’s Eye!
AGASA !
No GZK cutoff Consistent w/ GZK cutoff
AUGER 08
HiRes 2008
Spectrum facts !
There is an ankle
Galactic/Extragalactic transition?
Pair-production of pure-proton
source?
analyse composition!
or
There is a “cut-off”
GZK suppression?
Limit of the acceleration
process? Emax
analyse arrival directions!
or
Composition & Spectrum!
HEAT
High Elevation Angle Telescopes
AMIGA
Auger Muon and Infill Ground Array
Auger South Low Energy Extension !
20 km
20 km
Millard County
Utah/USA
24 x 24 Scintillators
(1.2 km spacing) 900 km2
~0.3 Auger South
3 x Fluorescence Stations
AGASA x 10 by stereo
Telescope Array !
Low Energy Hybrid
Extension
Aperture
1.4 103 km2 sr
Engel’08
knee
ankle
High Energy Cosmic Rays!
OBSERVABLES:
Spectrum
Composition
Sky Distribution
Composition-sensitive observables!
Depth of shower maximum development: Xmax
low E! high E! high E!
low A! high A!atmospheric
depth (g/cm2)!
Stochastic process large
fluctuations!
small
fluctuations!
Composition observable: !shower maximum !
Expectations from different hadronic models
+ fluctuations in Xmax smaller for heavier nuclei
Shower maximum over 2 decades in E!
+ fluctuations in Xmax to be exploited
Horizons for Etot=60 EeV!
Allard et al 08
Observed Composition
Allard et al ‘07
Shower maximum over 2 decades in E!
+ fluctuations in Xmax to be exploited
Shower maximum over 2 decades in E!
+ fluctuations in Xmax to be exploited
Shower maximum over 2 decades in E!
+ fluctuations in Xmax to be exploited
Need input from LHCf & TOTEM to
test Hadronic interaction models
?????
Photon limit!
Photon-induced showers look very different
Showers at E = 1019 eV, " = 0º :
Top-down models predict large UHE photon flux
SHDM models: decay of super-
heavy dark matter accumulated in
Galactic halo
TD models: supermassive particle
decay from topological defect
interaction or annihilation
Super heavy dark
matter (SHDM)
models are excluded
as UHECR sources!
Auger results (photon limit)!
Auger results (photon limit)!
Topological defects
(TD) are still possible
UHECR sources
Cosmologically Meaningful Termination!Implies Cosmogenic Neutrinos! !
GZK Cutoff
Greisen, Zatsepin, Kuzmin
1966
p+!cmb" #+ " p + $0
" n + $ +
Proton Horizon
~1020 eV
Auger results!TD models closer to
be constrained by
Auger neutrino limits
Neutrinos at EeV Soon!!
Neutrinos Soon!!
IceCube 22- !Point Source search!
2.2. sigma spot !
Bigas Cazon 06
Cosmogenic Neutrino
are just around the corner?
High Energy Cosmic Rays!
OBSERVABLES:
Spectrum
Composition
Sky Distribution
Main Auger result!
Highest energy cosmic rays have an anisotropic distribution!
First evidence that CR
astronomy is possible!
Correlation with z < 0.018 AGNs in
the 12th Véron-Cetty/Véron catalogue
Opening of a new era:
Study of particle acceleration in
HE astrophysical sources
Multi-messenger study of sources
HEP interactions at 300 TeV cm!
Auger main anisotropy result !
* - VCV AGN catalogue
- 27 highest energy events UHECRs
correlation is most significant above E = 56 EeV whre the CR flux drops…
(supports GZK interpretation)
Auger main anisotropy result !
Significance of the anisotropy result !Not an “AGN correlation” result!!
1st step: search for correlations between arrival directions of
UHECR and various source catalogues
Very large “raw significance” found w/ 12th VCV catalogue of AGNs
Did not seem to be fluctuation!
Auger collaboration set up a prescription for future data!
Even after generous penalty factors for a posteriori searches
and scanning of parameter space
(data from 2004/01/01 to 2006/05/26)
12 out of 15 events E > 56 EeV closer than 3.1° from an
AGN in 12th VCV with z ! 0.018 (D ! 75 Mpc)
Most significant a posteriori “correlation signal”:
3.2 expected
from isotropic
distribution
Significance of the anisotropy result !
2nd step: predefine a region in the sky of excess CR flux &
test if next UHECRs come from this region
Independent data set, prescribed parameters
unambiguous significance
Result: 99% CL that excess in the original data set is not a random
fluctuation from an isotropic CR distribution
CR distribution is anisotropic at the highest energies!!
Corroborated by other analyses, independent of source catalogue!
21% chance from isotropic distribution
8 correlating events out of 13 (2.7 expected)
Astrophysical Implications?!
UHECR sources are extragalactic!!!
They exist within the GZK sphere!!!!
What are the sources? Not clear yet!
Very low statistics to check against any specific model
YES!Can UHECRs come from AGNs?
Do UHECRs have to come from AGNs? NO!!
NOT Galactic Accelerators: Neutron Stars, Magnetars, Microquasars
shocks in the Galaxy
NOT very Distant Accelerators: Clusters of Galaxies(cluster shocks)
Quasars, BL Lacs
E = Ze B L!
10% efficiency
1020eV Protons
1020eV Iron
B(G)
L(cm)
others
GRBs
E = Ze B L!
10% efficiency
1020eV Protons
1020eV Iron
B(G)
L(cm)
others
GRBs
X
X
X X
Centaurus A, Virgo, etc. !
Centaurus A!
3.4 Mpc
AGN Acceleration Models
Astro/Phys Implications !
Intergalactic Fields Brms< 10-9 G (Mpc/Lc)1/2
If Proton Primaries - need to understand
>100 TeV interactions - Xmax, %Xmax, Nµ
+ Cosmogenic Neutrinos around the corner
If Heavy Primaries – need to understand
The Astrophysical Accelerators
+ Cosmogenic Neutrinos low flux
Magnetic Deflection
Plausible Bgalactic
E> 56EeV
Engel et al 08
What Next?!
Auger SOUTH 2007
Auger NORTH, JEM-EUSO, ….
Armengaud
10-3/Mpc3 AN+S 7 105L
Source Spectra!
Blasi & DeMarco
The Pierre Auger Observatory!of Ultra-High Energy Cosmic Rays!
Southern site
3 000 km2!
Northern site
20 000 km2!
Argentina!
Australia!Brasil!Bolivia*!Czech Republic!France # # !Germany !Italy!Mexico!Netherlands!Poland!
> 300 PhD scientists from !> 70 Institutions !and 17 countries!
Portugal# !Slovenia !Spain !UK#!USA!Vietnam*!
*Associate Countries!
Auger South Area !
Auger North Area!
Auger North in SE Colorado
Auger SOUTH & NORTH !Auger SOUTH
3,000 km2 = 1,157 mile2
Hexagonal grid -
1.5 km separation
FD sites - 4 (180o)
Auger NORTH
20,000 km2 ~ 8,000 mile2
SQUARE GRID -
1.414 mile separation
(2.26 km)
1 large PMT / tank 40 FD telescopes 7x Area for 2x the price
Auger NORTH !
1609 m!
1 mile!
Auger SOUTH
3,000 km2 = 1,157 mile2
Hexagonal grid - 1.5 km separation
FD sites - 4 (180o)
Auger NORTH
20,000 km2 ~ 8,000 mile2
SQUARE GRID -
1.414 mile separation
1 large PMT / tank 40 FD telescopes
Apertures & Energy Threshold!
Anisotropies
Nadir (2 yrs)
35o tilt (3 yrs)
- 3 x area, but
Eth > 1020 eV
Fluorescence only
~ 20% duty cycle
no muons info
Lin
dsle
ys
A New Era of AstroParticle Physics!Beginning to unveil the nature of !
the Most Energetic Accelerators in Nature!
UHE Cosmic Rays: Pierre Auger North, JEM-EUSO
HE Gamma-rays: FGST, HAWC, AGIS, CTA
HE Neutrinos: IceCube, Km3Net
A New Era of AstroParticle Physics!Beginning to unveil the nature of !
the Most Energetic Accelerators in Nature!
UHE Cosmic Rays: Pierre Auger North, JEM-EUSO
HE Gamma-rays: FGST, HAWC, AGIS, CTA
HE Neutrinos: IceCube, Km3Net
Particle Astrophysics @ UHEs!The Energy Frontier
TeV PeV EeV ZeV 12 15 18 21
12 15 18 21
12 15 18 21 !
&
CR
Leading & FUTURE Projects
IceCube Auger S
IceRay ANITA II
TA/TALE
Auger South
Auger S HAWC ! desert
ARIANNA
Auger North
Auger N
JEM EUSO
JEM EUSO
JEM EUSO Auger N KM3net
CTA
AGIS
FGST
AstroParticle Physics @ UHEs!The Energy Frontier
TeV PeV EeV ZeV 12 15 18 21
12 15 18 21
12 15 18 21 !
&
CR
Leading & FUTURE Projects
IceCube Auger S
IceRay ANITA II
TA/TALE
Auger South
Auger S HAWC ! desert
ARIANNA
Auger North
Auger N
JEM EUSO
JEM EUSO
JEM EUSO Auger N KM3net
CTA
AGIS GLAST