Transcript Collisions: Cosmic Accelerators

Collisions: Cosmic Accelerators
• the sky
> 10 GeV photon energy
< 10-14 cm wavelength
• > 108 TeV particles exist
• they should not
• more/better data
arrays of air Cherenkov telescopes
104 km2 air shower arrays
~ km3 neutrino detectors
f.halzen
CMB
Radio
Visibe
GeV g-rays
Flux
Energy (eV)
1 TeV
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/ TeV sources!
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cosmic
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rays
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n
With 103 TeV energy, photons do not
reach us from the edge of our galaxy
because of their small mean free path
in the microwave background.
g+g
+
e
+
e
Cosmic
Ray
spectrum
Atmospheric
neutrinos
Extragalactic flux
sets scale for many
Accelerator models
Telescope = Earth’s Atmosphere
Particle initiates electromagnetic + hadronic
cascade detected by:
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Electron/photon shower
Muon component
Cerenkov radiation
Nitrogen fluorescence
Neutrinos
fluorescence from atmospheric nitrogen
cosmic ray
o
+
_

+
_
 g
 n
fluorescent light
Acceleration to 1021eV?
~102 Joules
~ 0.01 MGUT
dense regions with exceptional
gravitational force creating relativistic
flows of charged particles, e.g.
•annihilating black holes/neutron stars
•dense cores of exploding stars
•supermassive black holes
Cosmic Accelerators
E ~ GcBR
R~
2
GM/c
energy
magnetic
field
E ~ GBM
boost
factor
mass
E~GBM
E > 1019 eV ?
•quasars
•blasars
•neutron stars
black holes
..
•grb
G @ 1 B @ 103G M @ 109 Msun
>
~ 10
G @ 1 B @ 1012G M @ Msun
>
~
102
emit highest energy g’s!
Supernova shocks
expanding in
interstellar medium
Crab nebula
Active Galaxies: Jets
20 TeV gamma rays
Higher energies obscured by IR light
VLA image of Cygnus A
Profile of Gamma Ray Bursts
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Total energy: one solar mass
Photon energy: 0.1 MeV to TeV
Duration: 0.1 secs -- 20 min
Several per day
Brightest object in the sky
Complicated temporal structure:
no ‘typical’ burst profile
Gamma
Ray
Burst
Two Puzzles or One?
• Gamma ray
bursts
• Source of the
highest energy
cosmic rays
Particles >
20
10
eV ?
•not protons
cannot reach us from cosmic accelerators
lint < 50 Mpc
no diffusion in magnetic fields
doublets, triplet
•not photons
g + Bearth e+ + e- not seen
showers not muon-poor
•not neutrinos
snp @ 10-5 spp
no air showers
Interaction length of protons
in microwave background
p + gCMB
lgp = (
 + ….
nCMB s
p+g
CMB
) -1
@ 10 Mpc
GZK cutoff
Forthcoming AGASA Results
• The highest energy cosmic rays do come
from point sources: 5 sigma correlation
between directions of pairs of particles.
Birth of proton astronomy!
• Are the highest energy cosmic rays Fe?
GKZ cutoff at ~2 1020 eV ?
Particles > 1020 eV ?
•not protons
new
astrophysics?
cannot reach us from cosmic accelerators
lint < 50 Mpc
no diffusion in magnetic fields
doublets, triplet trouble for top-down
scenarios
•not photons
g + Bearth e+ + e- not seen
showers not muon-poor
•not neutrinos
snp @ 10-5 spp
no air
snp @ spp with
showers
TeV - gravity unitarity?
24
10 eV
=
15
10
GeV ~_ MGUT
are cosmic rays the decay product of
•topological defects
(vibrating string, annihilating monopoles)
•heavy relics?
Top. Def.
X,Y
g
W,Z
quark + leptons
>> p
n
g
•top-down spectrum
•hierarchy n
g
p
The Oldest Problem in
Astronomy:
• No accelerator
• No particle candidate (worse than dark
matter!)
• Not photons (excludes extravagant
particle physics ideas)
What Now?
black hole
radiation
enveloping
black hole
cosmic ray
puzzle
protons
TeV g - rays
neutrinos
3
~
1
km
~
•atmospheric Cherenkov
high energy
air shower
•space-based
detectors
arrays
•AMANDA / Ice Cube
•Veritas,
Hess,
Magic
…
•Hi
Res,
Auger,
e.g.
Antares, Nestor,
•GLAST…
Airwatch,
NEMO
OWL, TA…
•particle physics
•short-wavelength
also
and cosmology
study of supernova
remnants and galaxies
•dark matter search
•discovery
104 km2
Array
=> Very large effective area (105 m2)
=> 3-dim shower reconstruction
=> Dramatic improvements in
- Energy Resolution
- Background Rejection
STACEE
Solar Tower Atmospheric Cherenkov Effect Experiment
Gamma-ray Astrophysics between 50-500 GeV
•Infrequently, a cosmic
neutrino is captured in
the ice, i.e. the neutrino
interacts with an ice
nucleus
•In the crash a muon
(or electron, or tau)
is produced
•The muon radiates blue light in its wake
•Optical sensors capture (and map) the light
Another example:
velocity muon > velocity light
Optical Cherenkov
Neutrino Telescope Projects
ANTARES
La-Seyne-sur-Mer, France
NEMO
Catania, Italy
BAIKAL
Russia
DUMAND
Hawaii
(cancelled 1995)
NESTOR
Pylos, Greece
AMANDA, South Pole, Antarctica
ANTARES SITE
40 km
Submarine cable
-2400m
40Km SE Toulon
Depth 2400m
Shore Base
La Seyne-sur-Mer
Atmospheric Muons and Neutrinos
Lifetime: 135 days
Triggered
Reconstructed
upgoing
Pass Quality Cuts
(Q ≥ 7)
Observed
Data
Predicted
Neutrinos
1,200,000,000
4574
5000
571
204
273
...online 2001 analysis
2 recent events:
October 7, 2001
October 10, 2001
...online 2001 analysis
Zenith angle comparison with signal MC
atmospheric muons
atmospheric n‘s
 real-time filtering at Pole
 real-time processing (Mainz)
Left plot:
 20 days (Sept/Oct 2001)
 90 ncandidates above 100°
4.5 ncandidates / day
(data/MC normalized above 100°)
IceCube
IceTop
AMANDA
South Pole
Skiway
• 80 Strings
• 4800 PMT
• Instrumented volume:
1 km3 (1 Gt)
• IceCube is designed to 1400 m
detect neutrinos of all
flavors at energies from
107 eV (SN) to 1020 eV
2400 m
South Pole
South Pole
Dark sector
Skiway
AMANDA
Dome
IceCube
Planned Location 1 km east
South Pole
Dark sector
Skiway
AMANDA
Dome
IceCube
The IceCube Collaboration
Institutions: 11 US and 9 European institutions
(most of them are also AMANDA member institutions)
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Bartol Research Institute, University of Delaware
BUGH Wuppertal, Germany
Universite Libre de Bruxelles, Brussels, Belgium
CTSPS, Clark-Atlanta University, Atlanta USA
DESY-Zeuthen, Zeuthen, Germany
Institute for Advanced Study, Princeton, USA
Dept. of Technology, Kalmar University, Kalmar, Sweden
Lawrence Berkeley National Laboratory, Berkeley, USA
Department of Physics, Southern University and A\&M College, Baton Rouge, LA, USA
Dept. of Physics, UC Berkeley, USA
Institute of Physics, University of Mainz, Mainz, Germany
Dept. of Physics, University of Maryland, USA
University of Mons-Hainaut, Mons, Belgium
Dept. of Physics and Astronomy, University of Pennsylvania, Philadelphia, USA
Dept. of Astronomy, Dept. of Physics, SSEC, PSL, University of Wisconsin, Madison, USA
Physics Department, University of Wisconsin, River Falls, USA
Division of High Energy Physics, Uppsala University, Uppsala, Sweden
Fysikum, Stockholm University, Stockholm, Sweden
University of Alabama, Tuscaloosa, USA
Vrije Universiteit Brussel, Brussel, Belgium
µ-event in
IceCube
AMANDA-II
Low Noise:
≈ 2 photoelectrons /
(5000 PMT x µsec)
1 km
Muon events
Eµ=6 PeV
Eµ=10 TeV
Measure energy by counting the number of fired PMT.
(This is a very simple but robust method)
ne+ e
W  + n
6400 TeV
PeV
t
(300m)
nt t
t decays
Why is Searching for n’s from GRBs
of Interest?
•Search for vacuum oscillations (n
Dm2 >~
10-17 eV2
•Test weak equivalence principle: 10-6
•Test
Cphoton - Cn : 10-16
Cn
nt):
Summary
• the sky
> 10 GeV photon energy
< 10-14 cm wavelength
• > 108 TeV particles exist
Fly’s Eye/Hires
• they should not
• more/better data
arrays of air Cherenkov telescopes
104 km2 air shower arrays
~ km3 neutrino detectors
/
/
/
/
/
/ TeV sources!
/
/
/
cosmic
/
/
rays
/
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/
/
n
A few more results …
• Gamma Ray Bursts (GRBs)
– Observation of single 3 s excess (GRB 970417a)
within 1997 BATSE trigger.
• Flux limit for unidentified TeV point sources
– For E spectrum
Flux (>1 TeV) < 2 – 30 x 10-7 cm-2 s-1 @ 90%
AMANDA II will probe this flux for
n/g = 1
However, g spectrum probably softer due to
reprocessing (core) and absorption in photon BG