Starting in academic year 2013/2014, the research group hosts a regular series of seminars, dedicated to our wide audience that includes physicists, students and engineers. These seminars feature excellent overviews presented by distinguished speakers and provide high value educational material for students . They prove to be the optimal venue for fruitful discussions between external experts and the group members.

The program for academic year 2022-2023 can be found below:

November 15th, 2022

(11:00, Campus Proeftuin (INW) – N3 lecture room)

Speaker: Jan Van Der Linden (KIT)

tt+heavy flavour measurements at the CMS experiment

Abstract: Ten years after the discovery of the Higgs boson at the Large Hadron Collider (LHC), measurements of Higgs boson couplings to other particles are performed at the Compact Muon Solenoid (CMS) experiment with high precision. One area of Higgs boson coupling measurements is the associated production of a pair of top quarks with a Higgs boson (tt+H). In this talk, I will talk about the challenges of a tt+H measurement and its relevancy for probing the consistency of the Standard Model (SM). I will put emphasis on the identification of bottom quarks, which is an important tool for accurate tt+H measurements, as both the Higgs boson and top quark predominantly decay into bottom quarks. Furthermore, I will discuss a dedicated measurement of the most important background process of tt+H, the associated production of a top quark pair and a bottom quark pair (tt+bb), and how improvements in that measurement directly benefit the tt+H measurement.

October 28th, 2022

(16:00, Campus Proeftuin – N3 lecture room)

Speaker: Sumit Kumar (AEI Hannover)

Cosmology in the era of third generation gravitational wave detectors
Abstract: The third-generation (3G) Gravitational wave (GW) detectors such as the Einstein telescope (ET) or Cosmic Explorer (CE) are expected to detect thousands of GW merger events per year with localization volumes less than a degree square. This will enable us to probe the large-scale structure (LSS) features such as baryon acoustic oscillations (BAO), clustering bias, etc, solely from the GW observations. In this talk, I will talk about the methods to detect LSS features such as BAO and clustering bias in 3G detectors era and their implications to do precision cosmology. Detection of LSS features as a function of redshift will help us in i) providing a complementary and independent probe to precision cosmology, and ii) strengthening the science case for the 3G detectors. I will show how detecting BAO features with GW observations might help in constraining the parameters for various cosmological models. The evolution of clustering bias can also help us in understanding the relation between clustering of baryonic matter and dark matter.