Particle Oscillations

Oscillations of particles are fascinating quantum-mechanical phenomenons. In October 2015 the discovery of neutrino oscillations was honoured by the Nobel price for physics. It is th first direct and experimental hint for physics beyond the standard model. Also the discovery of oscillation of neutral kaons lead to new insights of very fundamental questions. In this case it was the inititive for the discovery of CP-violation in weak interaction, which is one of the three Sacharov-conditions for explaining the assymmetry between matter and antimatter in the universe.

In detail we will discuss the following topics:

- Particle- antiparticle oscillations of neutral mesons. Fundamental experiments and theoretical description. Link to CP-violation in the quark system.

- Neutrinooscillations. Fundamental experiments and theoretical description. Conditions for coherence. Matter effects of solar neutrinos. Open questions and new ideas.

- Search for sterile neutrinos. Theoretical models and experimental status. Link to the question of dark matter in the universe

After successful completion of the module the students are able to:

• understand the basical quantummechanical descriptions which lead to the phenomenon of particle oscillations
• understand common aspects but also differences betwenn oscillations of hadrons (consisting of quark-antiquark systems)
• differentiate (pros and cons) between several experimental approaches to neutrino oscillations.

The module should motivate students to think deeper about open problems in particle physics and finally act as a bridge towards a successful MSc-thesis in this field of physics.

PH0016: Introduction in nuclear, particle and astrophysics are recommended. Students would benefit from the lectures Astroparticle physics I and II, but knowledge of both is not mandatory.

This module consists of a lecture and an exercise class.

In the thematically structured lecture the learning content is presented. With cross references between different topics the universal concepts in physics are shown. In scientific discussions the students are involved to stimulate their analytic-physics intellectual power.

In the exercise the learning content is deepened and exercised using problem examples and calculations. Thus the students are able to explain and apply the learned physics knowledge independently. In the exercise we will also explain and discuss the most important experiment in the field of particle oscillations in detail. This part is linked to the proseminar 'Methoss and detectors in Astroparticle physics'.

PPTX presentations and use of the blackboard.

Intensive discussion with students.

• F. Suekane: Neutrino Oscillations, Lecture Notes in Physics 898, Springer, (2014)
• F. Böhm & P. Vogel: Physics of Massive Neutrinos, Cambridge University Press, (1992)
• D. Perkins: High Energy Physics, Cambridge University Press, (2000)
• M. Thompson: Modern Particle Physics, Cambridge University Press, (2013)
• L. u. J. Oberauer: Neutrinophysik, Springer-Verlag, (2019)

The achievement of the competencies given in section learning outcome is tested exemplarily at least to the given cognition level using presentations independently prepared by the students. The exam of 20 minutes consists of the presentation of the results and a subsequent discussion.

For example an assignment in the exam might be:

• Direct and indirect CP-violation in oscillations of neutral mesons
• Experimental challenges to detect so-called "Mößbauer"-neutrinos
• How can we get hands on the neutrino mass ordering?
• How can we probe sterile neutrino oscillations?
• How can we measure CP-violation in the neutrino sector?
• Atmospheric ans solar neutrino experiments