Francesco Riggi has been full professor of Experimental Nuclear and Particle Physics in the Department of Physics and Astronomy at the University of Catania, Italy. He has been working in nuclear physics at low and high energy since 1974 and joined, at its inception, the ALICE Collaboration, a large experiment at the CERN Large Hadron Collider to study nuclear matter under extreme conditions. Within the ALICE Collaboration, he has contributed to the construction of the electromagnetic calorimeter and the silicon pixel detector, investigating the production of multistrange particles, short-lived resonances and light (anti)nuclei.

He has also been active in studying the physics of cosmic rays over the last 20 years, leading several projects concerning the use of cosmic muons in tomographic applications, and has served as a member of the educational project EEE, operating a wide network of cosmic ray telescopes. He is the author or the co-author of more than 600 scientific papers in all such areas and has contributed to various international conferences, as well as acting as a referee for various journals of nuclear and applied physics. He has also spent various periods abroad for research, in several European countries, the USA and Australia. As a professor at the Department of Physics and Astronomy in Catania, he has taught several courses in general and nuclear physics for 40 years. He is also the co-author of a textbook in experimental physics.

1 The discovery of the cosmic radiation

1.1 Introduction

1.2 Terrestrial radioactivity and first experiences with electroscopes

1.3 Investigations in the atmosphere

1.4 Victor Hess and the evidence for an extraterrestrial radiation

1.5 Towards a confirmation of Hess's results

2 Confirmation of the existence of a cosmic radiation

2.1 Further investigations in Europe during and after the First World War

2.2 Robert Millikan and the first US contributions to cosmic ray physics

2.3 The acceptance of the idea of a cosmic radiation

3 The nature of the cosmic radiation

3.2 Campaigns for measuring the intensity of cosmic radiation in various geographical locations

3.3 The debate on the corpuscular or radiative nature of cosmic radiation

3.4 Further contributions in Europe and other countries for understanding the nature of cosmic radiation

3.5 Protons as an essential component of primary radiation?

4 New particles and links with cosmic radiation

4.1 The discovery of new particles and the links with the understanding of cosmic radiation

4.2 The properties of the µ mesons

4.3 The discovery of the pion

4.4 The discovery of the neutron

5 The developments of the first techniques for the detection of cosmic radiation

5.1 Introduction

5.2 From Wulf's electroscopes to automatic recording equipment

5.3 Ionization chambers

5.4 Proportional counters

5.5 Wilson cloud chamber

5.6 The Geiger-Müller counters

5.7 Electronics and coincidence techniques

5.8 Nuclear emulsions

5.9 Detectors based on scintillators

6 The interaction of primary cosmics in the atmosphere

6.1 The first evidence of nuclear interactions of cosmic rays

6.2 Interactions in the atmosphere and first evidence of a complex primary radiation

6.3 Production of other particles in nuclear interactions

6.4 The role of high-altitude laboratories

7 Extensive air showers

7.1 Secondary processes and local showers

7.2 First evidence of the existence of extensive atmospheric showers

7.3 An "operational" definition and the first properties of extensive air showers

7.4 Towards a more complete description of the formation of extensive air showers

7.5 The study of atmospheric showers since the 1940s

7.6 The longitudinal development of an air shower

7.7 The transverse development of an air shower

7.8 The time profile of an air shower

8 The detection of extensive air showers

8.1 Direct and indirect methods

8.2 Arrays of particle detectors

8.3 Arrays based on the Cerenkov effect

8.4 Fluorescence detectors

8.5 Detection of radio waves associated with extended showers

8.6 An example of reconstruction of extensive air showers in the 1950s

8.7 Arrays for the reconstruction of extensive air showers

9 The primary cosmic radiation

9.1 Introduction

9.2 The hadronic component and the energy spectrum

9.3 The composition of the hadronic component

9.4 Electrons and positrons

9.5 Other components in the primary radiation

9.6 The intensity of primary radiation at different altitudes

9.7 Possible anisotropies in the primary radiation

10 The secondary cosmic radiation

10.1 Composition of the secondary radiation

10.2 Muons

10.3 Electrons

10.4 Gammas

10.5 Charged hadrons

10.6 Neutrons

10.7 Nuclei

11 The influence of the Earth

11.1 Introduction

11.2 The interaction with the atmosphere and meteorological effects

11.3 Influence of the Earth's magnetic field

11.4 Angular distribution of muons and East-West effect

11.5 The latitude effect

12 The secondary cosmic radiation and the influence of the Sun

12.1 Introduction

12.2 Periodic phenomena in the Sun and solar cycles

12.3 Modulation of the cosmic ray flux due to the Sun

12.4 Forbush variations

12.5 Other effects related to solar activity

13 Interaction of muons with matter

13.1 Introduction

13.2 Energy loss of muons

13.3 Range of muons in matter

13.4 Multiple scattering

14 Cosmic radiations underground, under water and under the ice

14.1 Introduction

14.2 Measurements underground

14.3 Measurements under water and under the ice

15 The origin of cosmic rays

15.1 Introduction

15.2 Some historical considerations about the acceleration mechanisms and the origin of cosmic rays

15.3 The Fermi acceleration mechanism

15.4 The role of supernovae

15.5 The high-energy extragalactic component

16 The impact of cosmic rays in applications and in daily life

16.1 Introduction

16.2 Production of radioactive isotopes by cosmics and dating techniques

16.3 Cosmic ray dating outside the Earth

16.4 The radiation dose produced by cosmic rays on Earth and in the solar system

16.5 Electronics and the effect of cosmic radiation

16.6 Muons and the origin of tomographic techniques

16.7 Tomographic techniques based on the absorption of cosmic muons

16.8 Muon tomography and scattering from materials with a high atomic number

16.9 Imaging techniques based on the production of secondary particles

16.10 Monitoring the stability of buildings by tracking cosmic muons

16.12 The impact of cosmics on cloud formation

16.13 Using extended atmospheric showers in time synchronization

Appendices

A1. A calculation of the flux at the top of the Eiffel Tower due to soil radioactivity

A2. The absorption coefficient in water and the directionality of cosmics. Millikan's calculation.

A3. Geographic and geomagnetic latitude

A4. The magnetic rigidity of particles

A5. The energy loss of charged particles and the estimate of the muon mass

A6. List of high-altitude observation stations in the mid-1950s

A7: An estimate of the particle density in an extensive air shower

A8. The relationship between altitude and atmospheric depth

A9. Gaisser-Hillas parameterization of the longitudinal profile of a shower

A10. The thickness of air crossed by a particle in the atmosphere

A11. Evaluation of the shower direction from the relative timing of several detectors

A12. Parameterizations of the muon spectrum at sea level

A12. The flux of underground muons

A13. Detection of bit-flip errors originated by cosmics