Theory Day Meeting

Friday 25 Feb 2022, 09:00 → 17:00 Europe/Amsterdam

The monthly theory day meeting aims to connect the various institutes of Nikhef. The program contains a light schedule of informal talks (one morning and one afternoon talk for in-person meetings, and only one afternoon talk for online meetings) with a lot of time to interact in between. Students are encouraged to join the student talks that are given by and for students only (no postdocs or staff allowed!). Our community is very broad ranging from low- to high-energy physics, from phenomenology to formal mathematics, so we encourage speakers to keep this in mind.

11:00 → 12:00 Student talk: “The unexplored landscape of the Cosmic Neutrino Background”

The sibling of the well known cosmic microwave background, the CNB, is notoriously difficult to detect and was thought to be unobservable for a long time. Only recently, serious efforts have been made to investigate the challenges we need to overcome to make the detection of these relic neutrinos a reality. The PTOLEMY collaboration is one of the pioneers in this regard. I will present to you the realm of possibilities this field has to offer, what we (believe to) already know about the CNB and what my colleagues and I are contributing to venture further into this unexplored landscape.

Speaker: Fabian Zimmer

14:00 → 14:45 Next-to-leading order corrections for gg->ZH with top quark mass dependence

We present for the first time a calculation of the complete next-to-leading order corrections to the gg→ZH process. We use the method of small mass expansion to tackle the most challenging two-loop virtual amplitude, in which the top quark mass dependence is retained throughout the calculations. We show that our method provides reliable numeric results in all kinematic regions, and present phenomenological predictions for the total and differential cross sections at the Large Hadron Collider and its future upgrades. Our results are necessary ingredients towards reducing the theoretical uncertainties of the pp→ZH cross sections down to the percent-level, and provide important theoretical inputs for future precision experimental collider programs. In this talk, I will start with a brief introduction to the small mass expansion and then show our new results for the ZH production at the LHC.

Speaker: Guoxing Wang

14:45 → 15:05 Plot of the month