Particle Physics Phenomenology

The most important milestones in particle physics are put in a historical perspective. We follow a century of scattering experiments, from Rutherford to LHC. We introduce successively the concept of the atomic nucleus, the study of β‎-decay and the proposal of the neutrino, the first internal symmetries, the Fermi theory and the Yukawa meson. In parallel we present the technical achievements in accelerator and detector technologies which made these advances possible. We end with the discovery of strange particles, the flavour SU(3) unitary symmetry, and the introduction of the quarks. This chapter follows a descriptive rather than a deductive approach and summa- rises many aspects of particle physics phenomenology which preceded the discovery of the Standard Model.

Deformed Kac–Moody algebra and noncommutative Fermi theory in two dimensions

Starting from noncommutative Fermi theory in two dimensions, we construct a deformed Kac–Moody algebra between its vector and chiral currents. The higher-order corrections to the deformed Kac–Moody algebra are explicitly calculated. We observe that the ordinary Schwinger terms are not affected by noncommutativity. Finally we conclude that the deformed Kac–Moody algebra can be given in term of ordinary Kac–Moody algebra plus infinitely many Lie algebraic structures at each nonzero power of the antisymmetric coefficient [Formula: see text].

Particle physics phenomenology with Python 3: $e^- + \bar{\nu}_e \to e^- + \bar{\nu}_e$ scattering in the Fermi theory

In this work, we develop an algorithm in Python 3 to compute the theoretical prediction of the electron and electron anti-neutrino scattering cross section using two different numerical methods: {\it i)} Riemann sums and {\it ii)} Monte Carlo integration. We compare the precision among these two methods and the theoretical result. Finally, the theoretical prediction is compared with the result obtained with MadGraph 5 which is commonly used to provide theoretical predictions for the LHC. With this project, we would like to encourage students to use programming languages as a tool for the study of new physics.

The thermopower of NiCr- and PtRh-alloys – a new view

For the interpretation of the Seebeck coefficient S(T) of transition metal alloys where one or both of the alloy partners develop a spin moment, so far spincluster models in connection with the standard Boltzmann-Fermi theory S(T)\sim T have been adopted. However, this interpretation suffers from some obvious inconsistencies, in particular with NiCr-alloys. In this contribution we try to alleviate these inconsistencies by implementing the recently proposed correlated electron thermopower terms which appear in the framework of Fermi-Boltzmann statistics when it is applied to Stoner-Slater intraatomic exchange (J) split electronic states. For both NiCr- and PtRh-alloys we recover the typical electron correlation term of the thermoelectric power, {S_{D}}, while former inconsistencies can be removed. As NiCr and PtRh-alloys are often used in high temperature sensing because of their stability, this new interpretation of the thermoelectric power may help to develop a better calibration and compositional choice of alloy-based thermocouples.