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Delve into the fascinating realm of cosmic accelerators and high-energy phenomena in the universe, analyzing collisions, cosmic rays, gamma-ray bursts, neutrinos, and more. Discover the mysteries behind the sources of the highest-energy cosmic rays, study the dynamics of extragalactic flux, and explore the intriguing puzzles surrounding gamma-ray bursts. Unravel the secrets of cosmic accelerators such as active galaxies, supernova shocks, and cosmic ray spectrum, shedding light on the most energetic processes in the cosmos. Venture into the forefront of astrophysics with groundbreaking research and cutting-edge technologies in the field of high-energy astrophysics.
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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
Energy (eV) 1 TeV Radio CMB Visibe GeV g-rays Flux
n / / / / / / / / / / / / / / / / / TeV sources! cosmic rays
With103 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 Extragalactic flux sets scale for many Accelerator models Atmospheric neutrinos
Telescope = Earth’s Atmosphere • Electron/photon shower • Muon component • Cerenkov radiation • Nitrogen fluorescence • Neutrinos Particle initiates electromagnetic + hadronic cascade detected by:
fluorescence from atmospheric nitrogen + _ cosmic ray + _ o fluorescent light electromagnetic shower
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 ~ GM/c2 magnetic field energy E ~GBM mass boost factor
E > 1019 eV ? E ~ GB M > ~ quasars G@ 1 B @ 103G M @109 Msun blasars 10 neutron stars G@ 1 B @ 1012G M @ Msun black holes . . grb 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 • 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 > 1020 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 10-5sppno air showers
Interaction length of protons in microwave backgroundp + gCMBp + …. lgp = (nCMBs ) -1 @10 Mpc p+gCMB 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 ? new astrophysics? • 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 10-5spp no air showers trouble for top-down scenarios snp@spp with TeV - gravity unitarity?
_ 1024 eV = 1015 GeV ~ MGUT are cosmic rays the decay product of • topological defects • (vibrating string, annihilating monopoles) • heavy relics? Top. Def. X,Y W,Z quark + leptons >> p g • top-down spectrum • hierarchy n gp
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 neutrinos protons TeV g - rays ~ 1 km3 high energy detectors ~ 104 km2 air shower arrays • atmospheric Cherenkov • space-based • AMANDA / Ice Cube • Antares, Nestor, • NEMO • Veritas, Hess, Magic … • GLAST… • Hi Res, Auger, • Airwatch, • OWL, TA… e.g. • particle physics • and cosmology • dark matter search • discovery • short-wavelength • study of supernova • remnants and galaxies also
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
Optical CherenkovNeutrino Telescope Projects ANTARES La-Seyne-sur-Mer, France BAIKAL Russia NEMO Catania, Italy DUMAND Hawaii (cancelled 1995) NESTOR Pylos, Greece AMANDA, South Pole, Antarctica
40Km SE Toulon Depth 2400m Shore Base La Seyne-sur-Mer ANTARES SITE 40 km Submarine cable -2400m