CTMP/UCT-CERN School on High-Energy Physics 2019

The school is open to students at the University of Cape Town and in South Africa and abroad with an in interest in particle physics, both theoretical and experimental.

Join us for a furious week of learning, discussions and interactions.

Dates:	Monday 18 - Friday 22 November 2019
Place:	Department of Physics, University of Cape Town
Organizers:	Heribert Weigert Cesareo Dominguez Tom Dietel Hubert Spiesberger

Timetable

This timetable is tentative and may be updated again before the start of the school.

Monday 18 Nov	Tuesday 19 Nov	Wednesday 20 Nov	Thursday 21 Nov	Friday 22 Nov
	9:00-10:30 Parallel QCD-B / TRD	9:00-10:30 Parallel T-QFT / TRD	9:00-10:30 Parallel QCD-B / TRD	9:00-10:30 Parallel T-QFT / TRD
	Coffee
	11:00-12:30 Plenary Thermal QFT Matias Säppi	11:00-12:30 Plenary QCD in B-fields Alejandro Ayala	11:00-12:00 Plenary Quark Masses Cesareo Dominguez	11:00-12:30 Plenary TBD
			Lunch
	Lunch			Closing
13:30-14:00 Welcome			13:00-14:00 Plenary Stong Coupling Constant Cesareo Dominguez
14:00-15:30 Parallel T-QFT / TRD	14:00-15:30 Parallel QCD-B / TRD	14:00-15:30 Parallel T-QFT / TRD	14:00-15:30 Parallel QCD-B / TRD
Discussion

Legend:

T-QFT	Putting a second T in QFT (Matias Säppi)
QCD-B	Quantum Chromo-Dynamics with Magnetic Fields (Alejandro Ayala)
TRD	Astroparticle Physics with the ALICE TRD(Tom Dietel)

Programme

The school covers selected topics related to research within the Centre for Theoretical and Mathematical Physics (CTMP) and the UCT-CERN Research Centre. The format consists of a few overview talks intended for a broad audience, as well as parallel streams of lectures and experimtal, hands-on activities. There will be ample time for discussions and interaction with the lecturers and other students.

Putting a second T in QFT

Speaker: Matias Säppi (University of Helsinki, Helsinki Institute of Physics)

In these five lectures, the goal is to introduce the formalism for including thermal effects in field theory. Starting with the knowledge of elementary nonthermal QFT, we will first discuss the standard modifications needed to formulate the path integral formalism of QFT at finite temperature in thermal equilibrium for different types of fields. Some standard limits familiar from classical statistical mechanics will appear from the QFT description (lec. 1-2). The formalism can be applied to gauge theories, using QCD as the main example, where it can be used to study systems like quark-gluon plasma in heavy-ion collisions and the early universe. (lec. 3) Some problems, such as IR divergences, specific to this setting arise, and addressing them with methods such as hard thermal loop resummation and dimensional reduction is introduced. (lec. 4) The lectures will finish with a quick look into another aspect of thermal field theory: QCD at finite density, and a brief discussion on its applications to neutron star physics (lec. 5).

 

Quantum Chromo-Dynamics with Magnetic Fields

Speaker: Alejandro Ayala (Universidad Nacional Autónoma de México)

 

Magnetic fields are present in a large variety of physical systems of interest including heavy-ion collisions, the interior of compact astrophysical objects and even the early universe. It has been estimated that the magnetic field strength |eB| in peripheral heavy-ion collisions reaches values equivalent to a few times the pion mass squared, both at RHIC and at the LHC. The effects of such magnetic fields cannot be overlooked in a complete description of these systems and its understanding contributes, at a fundamental level, to a better characterization of the properties of QCD matter. In these five lectures I will introduce the formalism to include magnetic fields within the QCD field theoretical framework. I will first introduce Schwinger’s proper time method (lects. 1 and 2) to include the effects of a constant and homogeneous magnetic field in the propagator of charged scalars, fermions and gauge bosons. I will then proceed to discuss the one-loop calculation for the modification of the gluon propagation properties in a magnetized medium with and without thermal effects (lect. 3). I will then discuss the modification of the strong coupling constant in a magnetized medium also with and without thermal effects (lect. 4). Finally, I will discuss some possible physical scenarios where experimental observations can be linked to the existence of magnetic fields. These include the chiral magnetic effect and the photon puzzle in relativistic heavy-ion collisions (lect. 5).

 

 

Determination of QCD Quark Masses and the Strong Coupling

Speaker: Cesareo Dominguez (UCT)

 

 

Determination of QCD Quark Masses: The analytical determination of the Quantum Chromodynamics quark masses, will be discussed, after a general introduction to the Renormalization Group Equation, QCD current correlation functions, and the notion of QCD-Hadron Duality.

Determination of the QCD strong coupling: The analytical determination of the strong quark-gluon coupling of Quantum Chromodynamics at the scale of the tau-lepton mass will be discussed, after a general introduction to the Renormalization Group Equation, QCD current correlation functions, and the notion of QCD-Hadron Duality.

 

 

Astroparticle Physics with the ALICE Transition Radiation Detector

Organizer: Thomas Dietel (UCT)

 

 

Every square metre of the Earth's surface is bombarded by about one hundred cosmic ray muons per second. These muons originate from primary cosmich rays, i.e. high-energy particles such as protons, nuclei, electrons or photons that hit the upper atmosphere. These collision of the primary cosmic rays with air molecules produce air showers that contain a multitude of intermediate particles that finally decay into mostly muons and photons.

We will use a readout chamber of the ALICE Transition Radiation Detector and two scintillationd detectors to measure these cosmic ray muons. In the course of this, we will learn more about primary and secondary cosmic rays and particle detectors.

The focus of this stream will be on hands-on work with the detector: setting up the detectors, operation and data taking with the available setup, the analysis of the recorded data and the interpretation of these measurements. The hands-on work will be complemented by short presentations and lectures on specific topics.