COSMIC RAY PHYSICS

The learning objectives of the Cosmic Ray Physics course consist of providing an overview on the properties of the charged "Cosmic Radiation" (Cosmic Rays): astrophysical sources of cosmic rays, transportation, propagation and acceleration of the primary cosmic rays in the galactic and extra-galactic environment, interaction and production of particle showers (secondary cosmic rays) in the terrestrial atmosphere, investigation of their Energy Spectrum, Mass Composition and Anisotropy in thei arrival direction on the Earth (at the top of atmosphere) with a particular attention to the high and ultra high energy intervals.

Moreover the techniques of direct and indirect measuremerements of the low, medium, high, very-high, ultra-high and extreme energy cosmic rays will be examined. The scientific results of the main past and present experiments in the Cosmic Ray Physics will be analysed, the status of works and the future perspectives will be discussed.

In particular, concerning the Dublin Descriptors, the course proposes the following objectives:

Knowledge and understanding:

• Critical understanding of the most advanced developments of Cosmic RAy Physics, both theoretical and experimental and phenomenological, and their interrelations, also across different subjects (Particle Physics, Astroparticle Physics, Astrophysics, Cosmology, Detector Techniques, Statistcs).
• Remarkable acquaintance with the scientific method, understanding of nature, and of the research in Cosmic Ray Physics by means of the study of the historical path, discoveries, development of the experimental methods and use of the instruments.

Applying knowledge and understanding

• Ability to identify the essential elements in a phenomenon, in terms of orders of magnitude and approximation level, and being able to perform the required approximations by means of investigation and understanding of different phenomena in Cosmic Ray Physics, in particular concerning the complex phenomenon of the Extensive Air Shower and on the capability to infer the properties of the primary cosmic rays starting from the measurements of the observables at ground by means of a backwards step-by-step well-structured process.
• Ability to plan and apply experimental and theoretical procedures to solve problems in academic or applied research, or to improve existing results by means of the detailed study, for instance, of the design regarding the main experiments in the field and the technological challenges needed to achieve the current knolewdge.
• Ability to develop new and innovative approaches and methods by means of detailed study and understanding of novel data analysis methods, statistical approaches and treatments od statistical and systematics errors used by the present experiments in the field.

Making judgements:

The

• ability to convey own interpretations of physical phenomena (discriminating reasoning)
• ability to identify the most proper methods to analyse critically, understand and process the experimental data
• ability to identify the predictions of a given theory or model

of the student are trained and tested during the course by means the introduction of three ongoing tests, named "In-depth Analysis" . In that test the student must individually study in detail one of the topics presented during the course. His in-depth analysis is based on the study of scientific peer-reviewed papers, on their elaboration and critical presentation in the form of seminar, by using blackboard or slides, during specific days within in the presence of other students that participate asking questions and discussing in a round table.

Communication skills

The

• ability to discuss about advanced physical concepts, both in Italian and in English
• ability to present one's own research activity or a review topic both to an expert and to an non-expert audience
• ability to explain in oral form with correct use of language and strictness in terminology a scientific topic, describing motivation and results
• ability to explain in writing form with correct use of language and strictness in terminology a scientific topic, describing motivation and results

of the student are trained and tested during the course, a part from the "In-Depth Analyses", by means of writing an essay (25 pages at maximum) and presenting a seminar on a selected topic based on the detailed study of original literature (three papers at minimum). That project represents the final examination for the student.

Learning skills

All the following main topics, considered in the Dublin Descriptor, in particular case:

• ability to acquire adequate tools for the continuous update of one's knowledge
• ability to access to specialized literature both in the specific field of one's expertise, and in closely related fields.
• ability to exploit databases and bibliographical and scientific resources to extract information and suggestions to better frame and develop one's study and research activity.
• ability to acquire, through individual study, knowledge in new scientific fields.

of the student are properly formed, encouraged, trained and testes during the Cosmic Ray Physics Course on the basis of the course contents (in particular concerning the study of main present experiments, the opportunity to access to the corresponding databases and bibliographic and scientific resources) and the custom of on-going seminars - a part from the final examination - that oblige the student to exercise oneself and implemnt all the above-mentioned abilities.

Lectures (class taught lessons) developed by the faculty member using slides projected by means of an overhead projector and partially carried out on the blackboard. Reading, in depth analysis and detailed study of reference scientific articles in the Cosmic Ray Physics sector. Articles and references will be provided lecture by lecture, before or during each lecture; collection of the slides used during each lecture will be given at the end of the course.

PLEASE NOTE: Should the circumstances require online or blended teaching, appropriate modifications to what is hereby stated may be introduced, in order to achieve the main objectives of the course. Moreover the exams may take place online, depending on circumstances.

0) Introduction: Cosmic Ray Physics in the context of the Astroparticle Physics

1) The discovery of the Cosmic Rays or Cosmic Radiation: the hystorical path

2) Introduction to the Cosmic Ray Physics: properties, origin, acceleration and propagation of the primary Cosmic Rays

3) The Extensive Air Showers (EAS)

4) Measurements of the Cosmic Rays for E<10^15eV (direct measurements)

5) Measurements of the Cosmic Rays for E>10^15 eV (indirect measurements): use of the Surface Detectors

6) Indirect measurements of the primary Cosmic Rays: use of the Fluorescence Detectors

7) The hybrid technique for the detection of the Extensive Air Showers

8) The Pierre Auger Observatory

1. T. Stanev "High Energy Cosmic Rays", Springer (Berlin, 2004)
2. M.S. Longair “High Energy Astrophysics” Cambridge University Press (Cambridge, 1990)
3. T.K. Gaisser "Cosmic Rays and Particle Physics", Cambridge University Press (Cambridge, 1990)
4. D. Perkins "Particle Astrophysics", Oxford University Press (Oxford, 2003)
5. Dr. Peter K.F. Grieder "Extensive Air Showers - High Energy Phenomena and Astrophysical Aspects A Tutorial, Reference Manual and Data Book" - Volume 1 & Volume 2 (Springer Verlag Berlin Heidelberg 2010)
6. A. De Angelis, M.Pimenta "Introduction to Particle and Astroparticle Physics - Multimessenger Astronomy and its Particle Physics Foundations" - Springer (1st edition, 2015)