Zeit, Ort:

11:15 Uhr, Otto Hahn lecture hall, library building, in-person or https://zoom.us/j/92430938606?pwd=NlZJMktybGU5UVlXYkd1OXVLT05VUT09

Redner:

Jun. Prof. Dr. Felix Kahlhöfer (KIT, Karlsruhe)

Titel:

The collider cosmology connection

Abstract: At first sight, the Large Hadron Collider (LHC) and Early Universe Cosmology have little in common, probing respectively the smallest and largest scales in nature. Nevertheless, one of the greatest successes of modern physics has been to demonstrate the deep connections between the two fields: The properties of fundamental particles affect the evolution of the early universe, and many models that modify cosmological observables can be tested at colliders. In my talk, I will illustrate this connection with three specific examples. First, I will demonstrate that searches for long-lived particles at the LHC can probe models that modify the expansion rate of the universe through non-thermal dark radiation. Second, I will show that early universe structure formation points towards self-interacting dark matter particles, which may give rise to highly unusual collider signatures. Finally, I will discuss how a global analysis of LHC searches may help us pin down the properties of dark matter particles.

Zeit, Ort:

11:15 Uhr, hybrid format: Otto Hahn lecture hall, library building or login via zoom: https://zoom.us/j/93897582983?pwd=c3V5UUxnTDRUOTAxM1hlSjM3VFN1UT09, Meeting-ID: 938 9758 2983, Kenncode: 138928

Redner:

Prof. Sera Markoff, Astronomical Institute Anton Pannekoek, University of Amsterdam

Titel:

What Event Horizon Telescope imaging can teach us about astroparticle physics

The physicist John Wheeler famously said “black holes have no hair”, however astrophysical black holes do end up driving pretty "hairy" systems around themselves when they accrete surrounding material. By the time the infalling gas approaches the event horizon, it has become a turbulent plasma hotter than the solar corona that generates and amplifies strong, and strongly ordered, magnetic fields. The most dramatic outcome of this process is the launching of enormous magnetised plasma structures called 'jets', that can extend well beyond their host galaxy and may be tapping the rotational energy of the black hole. These jets are also of great interest for astroparticle physics as primary candidates for the origin of ultra-high energy cosmic rays, neutrinos, and gamma-rays, attaining particle energies far beyond that of the LHC. After a brief refresher about the Event Horizon Telescope (EHT) and our key results so far, I will highlight their broader implications for our understanding of high-energy particle acceleration. In particular I will focus on what can be gained by combining EHT observations with those from other multi-wavelength and eventually also multi-messenger facilities. I will also give some perspective on what is (literally) on the horizon for these topics in the coming ~decade.

Zeit, Ort:

11:15 Uhr, Abteilungsseminarraum Lindner/Gentner Lab or Zoom

Redner:

Prof. Robert Ziegler (Freiburg)

Titel:

Looking for Axion Dark Matter with Flavor

https://zoom.us/j/93922533499?pwd=U2tscmt6RFJPenp3MzRBbzdNSTBqdz09Standard Model extensions with light axions are well-motivated by the observed Dark Matter abundance and the Peccei-Quinn solution to the Strong CP Problem. In general such axions can have large flavor-violating couplings to SM fermions, which naturally arise in scenarios where the Peccei-Quinn symmetry also explains the hierarchical pattern of fermion masses and mixings. After a pedagogical introduction, I will discuss how these couplings allow for efficient axion production from the decays of SM particles, giving the opportunity to probe axion Dark Matter with precision flavor experiments, astrophysics and cosmology

Zeit, Ort:

11:15 Uhr, hybrid format: Otto Hahn Lecture Hall, library building or login via zoom: https://zoom.us/j/93897582983?pwd=c3V5UUxnTDRUOTAxM1hlSjM3VFN1UT09, Meeting-ID: 938 9758 2983, Kenncode: 138928

Redner:

Christoph Langenbruch, RWTH Aachen

Titel:

Flavour anomalies: Status and Prospects

Abstract:Precision measurements of heavy flavour decays constitute powerful tests of the Standard Model of particle physics. New heavy particles beyond the Standard Model can significantly affect flavour observables through virtual quantum corrections. Precision measurements of these observables can reveal potential deviations from Standard Model predictions, and thereby probe energy scales far beyond the beam energies currently available at colliders. The talk will focus on flavour observables that have shown tensions with Standard Model predictions, the so-called flavour anomalies. I will discuss the current experimental status of the anomalies, and in particular focus on recent results on lepton universality.