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Calendar of Physics Talks Vienna
| An Informal Introduction to Higher Dagger Structures |
| Speaker: | Tim Lueders (University of Vienna) |
| Abstract: | The classical notion of a dagger structure enters physics for instance in certain formalizations of unitary quantum mechanics or in the description of very simple topological D-branes in orientifolds. More generally, the theory of higher dagger structures is meant to encode some of the rich structure of unitarity and defects in arbitrary (topological) quantum field theories.
We aim to keep our account elementary; no prior knowledge of higher category theory will be assumed.
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| Date: | Tue, 14.04.2026 |
| Time: | 14:00 |
| Duration: | 60 min |
| Location: | Erwin-Schroedinger-HS, Boltzmanngasse 5, 1090 Wien, 5.Stock |
| Contact: | S. Fredenhagen, M. Sperling |
| A precise alpha s determination from the R-improved QCD Static Energy |
| Speaker: | Jose Mena Valle (University of Salamanca) |
| Abstract: | The strong coupling alpha s is the most important parameter of Quantum Chromodynamics (QCD) therefore it is essential to determine it with high precision.This work presents an improved approach for extracting comparing the numerical results of lattice QCD simulations to the perturbative expansion of the QCD static energy. We apply R-improvement to its 3-loop fixed-order prediction, enabling the subtraction of the u=1/2 renormalon and the corresponding summation of large logarithms. We also perform resummation of large ultra-soft logs to LL accuracy using renormalization group equations.A new and more flexible parametrization of the renormalization scale has been implemented, allowing us to extend perturbation theory to distances of the order of 0.5 fm. |
| Date: | Tue, 14.04.2026 |
| Time: | 16:15 |
| Duration: | 60 min |
| Location: | Erwin-Schroedinger-HS, Boltzmanngasse 5, 1090 Wien, 5.Stock |
| Contact: | A. Hoang, M. Procura, J. Pradler |
| Free Neutron Decay with PERC |
| Speaker: | Johannes Schilberg (Atominstitut, TU Wien) |
| Abstract: | The PERC (Proton and Electron Radiation Channel) facility, located at the neutron source FRM II of the Technical University of Munich (TUM), serves as a clean source of neutron decay products (protons and electrons). PERC aims to contribute to the determination of the Cabibbo-Kobayashi-Maskawa quark-mixing element (Vud), measure the correlation coefficients of free neutron decay (a, A, b, C ) and search for new physics at the TeV scale. For this, all systematic errors will be controlled at 10-4 level. In order to achieve this, the PERC detector system will consist of a primary detector and two backscattering detectors to detect the 2% of electrons that are backscattered from the main detector. To ensure a low background for the detectors as well as to fulfil all radiation protection requirements, the PERC beamstop has been designed. Its components will consist of boron carbide (B4C) and |
| Date: | Wed, 15.04.2026 |
| Time: | 16:15 |
| Duration: | 45 min |
| Location: | Atominstitut, Helmut Rauch Hörsaal |
| Contact: | Elena Redchenko |
| Towards continuous mHz-superradiance in strontium |
| Speaker: | Elisa Wenzel (University of Amsterdam) |
| Abstract: | Superradiance is a collective light-matter phenomenon with the potential of significantly enhancing the short-term stability of optical clocks. Our goal is to generate continuous superradiant lasing on the millihertz-linewidth transition in strontium. While pulsed superradiance on this transition has already been demonstrated, achieving continuous operation requires a steady supply of ultracold atoms actively transported through the lasing region. I will present our experimental setup designed towards this goal, including my work on transport, molasses cooling, and laser intensity stabilization. |
| Date: | Thu, 16.04.2026 |
| Time: | 09:00 |
| Duration: | 45 min |
| Location: | Library Atominstitut |
| Contact: | Tim Langen |
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