Particles and Astrophysics (eBook)

Maurizio Spurio is a Professor of Physics at the University of Bologna where he teaches Particle and Astroparticle physics. With his research he is involved in experimental physics, with particular interest in high-energy physics without particle accelerators and astroparticle physics.He was member of the MACRO experiment at Gran Sasso underground laboratory, which provided a deep study of the penetrating component of the cosmic radiation including the observation of atmospheric neutrino oscillations. Since 2001 he is member of the ANTARES experiment (the first neutrino telescope in the sea), currently in charge as deputy spokesperson.Professor Spurio has already co-authored/edited 4 Springer books.

Preface 7
Contents 9
1 An Overview of Astroparticle Physics 17
1.1 Introduction 17
1.1.1 Astrophysics and Astroparticle Physics 19
1.1.2 Discoveries and Experiments Not Covered in This Book 22
1.2 Cosmic Rays 23
1.3 Gamma-Rays of GeV and TeV Energies 26
1.4 Neutrino Astrophysics 27
1.5 The Dark Universe 31
1.6 Laboratories and Detectors for Astroparticle Physics 32
1.6.1 Space Experiments 32
1.6.2 Experiments in the Atmosphere 33
1.6.3 Ground-Based Experiments 34
1.7 Underground Laboratories for Rare Events 34
References 37
2 The Cosmic Rays and Our Galaxy 38
2.1 The Discovery of Cosmic Rays 38
2.2 Cosmic Rays and the Early Days of Particle Physics 41
2.3 The Discovery of the Positron and Particle Detectors 42
2.3.1 The Motion in a Magnetic Field and the Particle Rigidity 42
2.3.2 The Identification of the Positron 44
2.4 A Toy Telescope for Primary Cosmic Rays 47
2.5 Differential and Integral Flux 49
2.6 The Energy Spectrum of Primary Cosmic Rays 52
2.7 The Physical Properties of the Galaxy 55
2.7.1 The Galactic Magnetic Field 57
2.7.2 The Interstellar Matter Distribution 59
2.8 Low-Energy Cosmic Rays from the Sun 60
2.9 The Effect of the Geomagnetic Field 62
2.10 Number and Energy Density of the Cosmic Rays 65
2.11 Energy Considerations on Cosmic Ray Sources 67
References 68
3 Direct Cosmic Rays Detection: Protons, Nuclei, Electrons and Antimatter 70
3.1 Generalities on Direct Measurements 71
3.2 The Calorimetric Technique 72
3.2.1 Hadronic Interaction Length and Mean Free Path 73
3.2.2 The Electromagnetic Radiation Length 74
3.2.3 Hadronic Interaction Length and Mean Free Path in the Atmosphere 75
3.3 Balloon Experiments 76
3.4 Satellite Experiments 79
3.4.1 The IMP Experiments 79
3.4.2 The PAMELA Experiment 81
3.5 The AMS-02 Experiment on the International Space Station 82
3.6 Abundances of Elements in the Solar System and in CRs 85
3.6.1 Cosmic Abundances of Elements 88
3.7 Energy Spectrum of CR Protons and Nuclei 91
3.8 Antimatter in Our Galaxy 93
3.9 Electrons and Positrons 95
3.9.1 The Positron Component 97
3.9.2 Considerations on the e+,e- Components 99
References 100
4 Indirect Cosmic Rays Detection: Particle Showers in the Atmosphere 102
4.1 Introduction and Historical Information 103
4.2 The Structure of the Atmosphere 104
4.3 The Electromagnetic (EM) Cascade 107
4.3.1 Heitler's Model of EM Showers 108
4.3.2 Analytic Solutions 110
4.4 Showers Initiated by Protons and Nuclei 114
4.4.1 The Muon Component in a Proton-Initiated Cascade 117
4.4.2 The EM Component in a Proton-Initiated Cascade 118
4.4.3 Depth of the Shower Maximum for a Proton Shower 121
4.4.4 Showers Induced by Nuclei: The Superposition Model 122
4.5 The Monte Carlo Simulations of Showers 125
4.6 Detectors of Extensive Air Showers at the Energy of the Knee 127
4.6.1 A Toy Example of an EAS Array 128
4.6.2 Some EAS Experiments 131
4.6.3 Cherenkov Light Produced by EAS Showers 133
4.7 The Time Profile of Cascades 135
4.8 The Arrival Direction of CRs as Measured with EAS Arrays 136
4.9 The CR Flux Measured with EAS Arrays 139
4.10 Mass Composition of CRs Around the Knee 141
4.10.1 The Ne Versus N? Method 142
4.10.2 Depth of the Shower Maximum 143
References 145
5 Diffusion of Cosmic Rays in the Galaxy 147
5.1 The Overabundance of Li, Be, and B in CRs 148
5.1.1 Production of Li, Be, and B During Propagation 149
5.2 Dating of Cosmic Rays with Radioactive Nuclei 153
5.2.1 Unstable Secondary-to-Primary Ratios 155
5.3 The Diffusion-Loss Equation 156
5.3.1 The Diffusion Equation with Nuclear Spallation 159
5.3.2 Numerical Estimate of the Diffusion Coefficient D 160
5.4 The Leaky box Model and its Evolutions 161
5.5 Energy-Dependence of the Escape Time ?esc 163
5.6 Energy Spectrum of Cosmic Rays at the Sources 165
5.7 Anisotropies due to the Diffusion 166
5.7.1 The Compton--Getting Effect 169
5.8 The Electron Energy Spectrum at the Sources 169
5.8.1 Synchrotron Radiation 170
5.8.2 Measured Energy Spectrum of Electrons 174
5.8.3 Average Distance of Accelerators of Electrons 175
References 176
6 Acceleration Mechanisms and Galactic Cosmic Ray Sources 178
6.1 Second- and First-Order Fermi Acceleration Mechanisms 179
6.1.1 Magnetic Mirrors 180
6.1.2 The Second-Order Fermi Acceleration Mechanism 182
6.1.3 The First-Order Fermi Acceleration Mechanism 184
6.1.4 The Power-Law Energy Spectrum from the Fermi Model 187
6.2 Diffusive Shock Acceleration in Strong Shock Waves 187
6.2.1 Supernova Explosions and Cosmic Rays Acceleration 189
6.2.2 Relevant Quantities in a Supernova Explosion 190
6.3 Maximum Energy Attainable in the Supernova Model 193
6.4 The Spectral Index of the Energy Spectrum 195
6.4.1 The Escape Probability 197
6.4.2 A Shock Front in a Mono-Atomic Gas 198
6.5 Success and Limits of the Standard Model of Cosmic Ray Acceleration 201
6.6 White Dwarfs and Neutron Stars 203
6.6.1 White Dwarfs 204
6.6.2 Neutron Stars and Pulsars 206
6.7 Possible Galactic Sources of Cosmic Rays Above the Knee 210
6.7.1 A Simple Model Involving Pulsars 211
6.7.2 A Simple Model Involving Binary Systems 212
References 213
7 Ultra High Energy Cosmic Rays 215
7.1 The Observational Cosmology and the Universe 216
7.2 The Large-Scale Structure of the Universe 218
7.3 Anisotropy of UHECRs: The Extragalactic Magnetic Fields 220
7.4 The Quest for Extragalactic Sources of UHECRs 222
7.5 Propagation of UHECRs 227
7.5.1 The Adiabatic Energy Loss 227
7.5.2 The Propagation in the CMB: The GZK Cut-Off 227
7.5.3 epm Pair Production by Protons on the CMB 230
7.5.4 Propagation in the Extragalactic Magnetic Field 231
7.6 The Fluorescence Light and Fluorescence Detectors 232
7.7 UHECR Measurements with a Single Technique 237
7.7.1 Results from HiRes and AGASA 238
7.8 Large Hybrid Observatories of UHECRs 240
7.9 The Flux of UHECRs 245
7.10 The Chemical Composition of UHECRs 246
7.11 Correlation of UHECRs with Astrophysical Objects 248
7.12 Constraints on Top-Down Models 250
7.13 Summary and Discussion of the Results 251
References 253
8 The Sky Seen in ?-rays 254
8.1 The Spectral Energy Distribution (SED) and Multiwavelength Observations 255
8.2 Astrophysical ?-rays: The Hadronic Model 257
8.2.1 Energy Spectrum of ?-rays from ?0 Decay 258
8.3 Galactic Sources and ?-rays 260
8.3.1 A Simple Estimate of the ?-ray Flux from a Galactic Source 261
8.4 Astrophysical ?-rays: The Leptonic Model 262
8.4.1 The Synchrotron Radiation from a Power-Law Spectrum 263
8.4.2 Synchrotron Self-Absorption 265
8.4.3 Inverse Compton Scattering and SSC 266
8.5 The Compton Gamma Ray Observatory Legacy 270
8.5.1 The EGRET ?-ray Sky 270
8.6 Fermi-LAT and Other Experiments for ?-ray Astronomy 273
8.6.1 The Fermi-LAT 273
8.6.2 AGILE and Swift 275
8.7 Diffuse ?-rays in the Galactic Plane 275
8.7.1 An Estimate of the Diffuse ?-ray Flux 278
8.8 The Fermi-LAT Catalogs 279
8.9 Gamma Ray Bursts 284
8.9.1 Classification of GRBs 287
8.10 Limits of ?-ray Observations from Space 290
References 291
9 The TeV Sky and Multiwavelength Astrophysics 292
9.1 The Imaging Cherenkov Technique 293
9.1.1 Gamma-Ray Versus Charged CR Discrimination 295
9.1.2 HESS, VERITAS and MAGIC 296
9.2 EAS Arrays for ?-astronomy 299
9.2.1 Sensitivity of ?-ray Experiments 300
9.3 TeV Astronomy: The Catalog 301
9.4 Gamma-Rays from Pulsars 304
9.5 The CRAB Pulsar and Nebula 305
9.6 The Problem of the Identification of Galactic CR Sources 307
9.7 Extended Supernova Remnants 308
9.7.1 The SED of Some Peculiar SNRs 310
9.8 Summary of the Study of Galactic Accelerators 314
9.9 Active Galaxies 315
9.10 The Extragalactic ?-ray Sky 318
9.11 The Spectral Energy Distributions of Blazars 319
9.11.1 Quasi-Simultaneous SEDs of Fermi-LAT Blazars 320
9.11.2 Simultaneous SED Campaigns and Mrk 421 322
9.12 Jets in Astrophysics 324
9.12.1 Time Variability in Jets 325
9.13 The Extragalactic Background Light 326
References 330
10 High-Energy Neutrino Astrophysics 331
10.1 The CRs, ?-rays and Neutrino Connection 332
10.1.1 Neutrino Detection Principle 333
10.2 Background in Large Volume Neutrino Detectors 335
10.3 Neutrino Detectors and Neutrino Telescopes 337
10.3.1 Muon Neutrino Detection 338
10.3.2 Showering Events 340
10.4 Cosmic Neutrino Flux Estimates 341
10.4.1 A Reference Neutrino Flux from a Galactic Source 341
10.4.2 Extragalactic Diffuse Neutrino Flux 343
10.4.3 Neutrinos from GRBs 345
10.4.4 Cosmogenic Neutrinos 348
10.5 Why km3-Scale Telescopes 348
10.5.1 The Neutrino Effective Area of Real Detectors 351
10.5.2 Number of Optical Sensors in a Neutrino Telescope 352
10.6 Water and Ice Properties 353
10.7 Operating Neutrino Telescopes 355
10.7.1 A Telescope in the Antarctic Ice 355
10.7.2 A Telescope in the Mediterranean Sea 357
10.8 Results from Neutrino Telescopes 359
10.8.1 Point-Like Sources 359
10.8.2 Limits from GRBs and Unresolved Sources 362
10.9 The First Measurement of Cosmic Neutrinos 363
References 367
11 Atmospheric Muons and Neutrinos 368
11.1 Nucleons in the Atmosphere 369
11.2 Secondary Mesons in the Atmosphere 372
11.3 Muons and Neutrinos from Charged Meson Decays 376
11.3.1 The Conventional Atmospheric Neutrino Flux 378
11.3.2 The Prompt Component in the Muon and Neutrino Flux 378
11.4 The Particle Flux at Sea Level 379
11.5 Measurements of Muons at Sea Level 382
11.6 Underground Muons 383
11.6.1 The Depth--Intensity Relation 384
11.6.2 Characteristics of Underground/Underwater Muons 384
11.7 Atmospheric Neutrinos 386
11.7.1 Early Experiments 388
11.8 Oscillations of Atmospheric Neutrinos 390
11.9 Measurement of Atmospheric ?? Oscillations in Underground Experiments 391
11.9.1 Event Topologies in Super-Kamiokande 391
11.9.2 The Iron Calorimeter Soudan 2 Experiment 396
11.9.3 Upward-Going Muons and MACRO 397
11.10 Atmospheric ?? Oscillations and Accelerator Confirmations 400
11.11 Atmospheric Neutrino Flux at Higher Energies 402
References 403
12 Connections Between Physics and Astrophysics of Neutrinos 405
12.1 Stellar Evolution of Solar Mass Stars 406
12.2 The Standard Solar Model and Neutrinos 408
12.3 Solar Neutrino Detection 413
12.4 The SNO Measurement of the Total Neutrino Flux 417
12.5 Oscillations and Solar Neutrinos 420
12.6 Oscillations Among Three Neutrino Families 422
12.6.1 Three Flavor Oscillation and KamLAND 424
12.6.2 Measurements of ?13 425
12.7 Matter Effect and Experimental Results 426
12.8 Summary of Experimental Results and Consequences for Neutrino Astrophysics 429
12.8.1 Effects of Neutrino Mixing on Cosmic Neutrinos 430
12.9 Formation of Heavy Elements in Massive Stars 432
12.10 Stellae Novae 433
12.11 Core-Collapse Supernovae (Type II) 434
12.11.1 GRB Supernovae 439
12.12 Neutrino Signal from a Core-Collapse SN 439
12.12.1 Supernova Rate and Location 439
12.12.2 The Neutrino Signal 440
12.12.3 Detection of Supernova Neutrinos 441
12.13 The SN1987A 444
12.14 Stellar Nucleosynthesis of Trans-Fe Elements 445
References 446
13 Microcosm and Macrocosm 448
13.1 The Standard Model of the Microcosm: The Big Bang 449
13.2 The Standard Model of Particle Physics and Beyond 452
13.3 Gravitational Evidence of Dark Matter 453
13.4 Dark Matter 455
13.5 Supersymmetry 457
13.5.1 Minimal Standard Supersymmetric Model 458
13.5.2 Cosmological Constraints and WIMP 459
13.6 Interactions of WIMPs with Ordinary Matter 461
13.6.1 WIMPs Annihilation 462
13.6.2 WIMPs Elastic Scattering 463
13.7 Direct Detection of Dark Matter: Event Rates 465
13.8 WIMPs Direct Detection 468
13.8.1 Solid-State Cryogenic Detectors 469
13.8.2 Scintillating Crystals 470
13.8.3 Noble Liquid Detectors 471
13.8.4 Present Experimental Results and the Future 472
13.9 Indirect WIMPs Detection 474
13.9.1 Neutrinos from WIMP Annihilation in Massive Objects 474
13.9.2 Gamma-Rays from WIMPs 477
13.9.3 The Positron Excess: A WIMP Signature? 478
13.10 What's Next? 480
References 482
Index 484