CPT

Calendar of Physics Talks Vienna

Holography for Flatspace: The Carroll Perspective.
Speaker:Arjun Bagchi (Indian Inst. Tech., Kanpur)
Abstract:Recent attempts at constructing holography for asymptotically flat spacetimes have followed two distinct directions: Celestial and Carrollian holography. In this talk, we provide an overview of the Carroll perspective which has had successes in lower dimensions previously. We then provide an answer to one of the most pressing questions in this formulation: how does one understand scattering in flat space from Carrollian CFTs.
Date: Tue, 14.06.2022
Time: 14:00
Duration: 60 min
Location:Sem.R. DA, gruen 05 (TU Wien, Freihaus)
Contact:D. Grumiller, S. Fredenhagen, E. Battista, R. Ruzziconi

Towards Operando Modelling in Zeolites: Solvation, Encapsulation, Diffusion
Speaker:Christopher Heard (Charles University, Dep. Of Physical and Macromolecular Chemistry)
Abstract:Zeolites represent an important class of environmentally friendly and commercially available solid catalysts and are produced at the Mega-tonne scale. Optimal utilization requires an atomistic understanding of framework structure, as well as both reactive and non-reactive processes occurring within the micropore. However, intercage diffusion, cluster agglomeration and redispersion are complex processes which generally occur on timescales too long for traditional computational modelling methods. We tackle this problem via the development of flexible, reactive neural network potentials with density functional theory accuracy, which dramatically extend sampling quality, and allow for investigations of complex, reactive environments in zeolites. In this talk I will discuss recent developments from our group towards operando modelling of zeolites, including the training of multi-elemental, re
Date: Tue, 14.06.2022
Time: 16:00
Location:TU Wien, Institut für Angewandte Physik, E134 1040 Wien, Wiedner Hauptstraße 8-10 Yellow Tower „B“, 5th floor, SEM.R. DB gelb 05 B; The seminar will be also held as a Zoom Meeting https://tuwien.zoo
Contact:Prof. Gareth Parkinson PhD

Top mass calibration for Monte-Carlo event generators
Speaker: Oliver Jin (Universität Wien)
Abstract:The relation between the top quark mass parameters of Monte-Carlo event generators and renormalized and well-defined Lagrangian masses is not very well understood and a subject of intense discussions in the community given that the current experimental uncertainties in direct top mass determinations is at the level of 300 MeV. A calibration framework has been developed to determine this relation numerically by using hadron level N2LL accurate theoretical predictions for e+e- to ttbar event shapes expressed in the pole or MSR mass. In this presentation I will talk about crucial improvements to this framework and provide a first look at observable universality and a preliminary comparison between the major Monte-Carlo event generators Pythia, Herwig and Sherpa.
Date: Tue, 14.06.2022
Time: 16:15
Duration: 60 min
Location:Erwin Schroedinger Hoersaal, Fakultaet für Physik, Boltzmanngasse 5, 5. Stock ZOOM https://univienna.zoom.us/j/93427906843?pwd=YjhSejdUVW16QjVQYUh5TVNSNFNhQT09 Meeting I
Contact:A. Hoang, M. Procura

Sub-eV neutrino mass limit from KATRIN
Speaker:Prof. Christian Weinheimer (Westfaelische Wilhelms-Universitaet, Muenster, Germany)
Abstract:Since the discovery of neutrino oscillation, we know that neutrinos have a non-zero mass, but we do not know the absolute neutrino mass scale, which is as important for cosmology as for particle physics. The direct search for a non-zero neutrino mass using weak decay endpoint spectra is complementary to the search for 0nu2b-decays and the analysis of cosmological data. The Karlsruhe tritium neutrino experiment KATRIN investigates the endpoint region of the tritium beta decay. KATRIN uses a powerful, windowless, gaseous molecular tritium source in combination with a giant MAC-E filter as an electron spectrometer. To achieve its sub-eV sensitivity, KATRIN has pushed many technologies to their limits and uses sophisticated calibration techniques. From early 2019, KATRIN is taking highly statistical tritium data... [full abstract available here: https://indico.cern.ch/event/1167510/]
Date: Wed, 15.06.2022
Time: 17:00
Duration: 60 min
Location:SMI Seminarraum, Kegelgasse 27, 3. Stock (online participation possible: request zoom link before 12:00 of June 15th via email martin.simon at oeaw.ac.at)
Contact:Eberhard Widmann, Martin Simon