KUTS14

7 Apr 2025, 08:00 → 9 Apr 2025, 22:00 Europe/Berlin

Gustav-Mie-Haus (ground floor) (University of Freiburg)

The "Precision SUSY Higgs Mass Calculation Initiative" (also known as KUTS) was launched in 2014 to provide a forum for discussions between the different groups involved in Higgs-mass calculations in supersymmetric (SUSY) models.

After eleven biannual meetings held in nine different European institutes (see the web page https://sites.google.com/site/kutsmh/), a working-group report was published at the end of 2020 (Eur.Phys.J.C 81 (2021) 5, 450). The report provided a comprehensive overview of Higgs-mass calculations in SUSY models, documented all of the developments discussed during the KUTS meetings, and outlined the prospects for future improvements. After a COVID-imposed hiatus, the scope of the initiative was broadened to include other kinds of precision calculations in BSM models. The 12th meeting was held at CERN in 2023, and the 13th meeting was held in DESY in 2024.

It is now time for the 14th meeting, which will take place at University of Freiburg from Monday, 7 April to Wednesday, 9 April. Participants are encouraged to present any BSM precision calculation they have been particularly interested in since the last meeting. Topics may range from Higgs-mass calculations in SUSY models, to precision calculations of several Higgs-boson properties – and possibly of other observables in the EW sector, such as the W-boson mass – in both SUSY and non-SUSY BSM models. Some time will also be left aside for further discussions on the aims and boundaries of the renewed KUTS initiative.

The meeting will follow the same format as in the original KUTS workshops: three days (one afternoon, one full day, one morning) in which relatively few talks are presented and discussions proceed freely, without a strict schedule.

Warning: Please beware! Some participants may receive fraudulent emails claiming to be from a company tasked with arranging accommodations for participants. These emails are scams.

 

Organizing Committee                      

• M. Gabelmann (U. Freiburg, LOC) 
• H. Rzehak (U. Freiburg, LOC)
• S. Heinemeyer (IFT/CSIC Madrid)
• P. Slavich (LPTHE)

Monday 7 April

1 LOC: Welcome

KUTSstart.pdf

2 Opening

Speaker: Pietro Slavich (LPTHE Paris)

KUTS14.pdf

3 Sparticle Decays at NLO QCD and Intelligent Scans in the NMSSM

The next-to-minimal supersymmetric extension of the Standard Model (NMSSM) belongs to the most prominent, best motivated and experimentally widely tested beyond-SM extensions. For a meaningful interpretation of the experimental results and in order to be able to pin down the model underlying nature from the theory side, precise predictions for observables and parameters are crucial. Moreover, in view of the SM-like nature of the Higgs boson all relevant experimental and theoretical constraints have to be considered to corner valid new physics models. The code NMSSMCALC computes Higgs potential parameters and decays, including higher-order corrections. As an additional step in obtaining observables and predictions, the supersymmetric particle decays have to be calculated. Finally, because of the non-minimal number of input parameters, an intelligent scan procedure of the parameter space is required in order to investigate the parameter space, taking into account all relevant constraints and then providing interesting benchmark points. In this talk, we present our recent progress in incorporating the supersymmetric particle decays (including 2-body decays with NLO QCD corrections, 3-body decays, and radiative decays). We then also discuss the setup of a program chain for the performance of intelligent scans (e.g. via Markov chain Montecarlo or active learning) in the NMSSM with the tool BSMArt and other tools to check for experimental limits and constraints. Finally, we present some sample benchmark results.

Speaker: Felix Egle

Presentation_KUTS_FelixEgle.pdf

16:30 Coffee

4 Effective Field Theories for Heavy Higgs Bosons in Standard Model Extensions

We integrate out the heavy scalar mass eigenstate in a real Higgs singlet extension of the Standard Model at one-loop order, taking into account full mixing and renormalization. We discuss the choice of a proper decoupling limit and matching of the result on SMEFT versus HEFT. Finally we validate convergence of predictions from the effective theory to the full result for a chosen set of electroweak precision observables.

Speaker: Sebastian Schuhmacher

KUTS2025Slides.pdf

Tuesday 8 April

5 Renormalization of the general Two-Higgs-Doublet Model

The Two-Higgs-Doublet Model (THDM) is one of the simplest and most extensively studied extensions of the Standard Model of particle physics (SM). It offers a rich phenomenology, and can, depending on the region in parameter space, address phenomena such as the observed matter-antimatter asymmetry in the universe and dark matter, which cannot be fully explained by the SM.\\ When computing perturbative predictions for observables in the THDM (or any given QFT model), the choice of renormalization scheme should have no effect on all-order results. However, due to the truncation of the perturbation series, this choice affects the properties of finite-order predictions, such as gauge (in)dependence and perturbative stability. Therefore, it is valuable to study and compare different renormalization schemes with the goal of optimizing for such properties.\\ In this talk, we will give a brief description of the general THDM and explain the renormalization procedure we performed. Different renormalization schemes will be compared.

Speaker: Robin Feser

6 Renormalization of the C2HDM and the role of m3

Speaker: Duarte Fontes

C2HDM_DFontes.pdf

11:00 Coffee

7 Two-Loop Corrections to Trilinear Higgs Couplings in Higgs BSM models

The precise determination of the Higgs self-couplings is an essential task for understanding electroweak symmetry breaking and probing physics beyond the Standard Model (SM). The calculation of two-loop corrections is important to provide a critical test of the perturbative stability, especially in the case of large one-loop corrections that can occur in scenarios with extended scalar sectors. Morever, they need to be taken into account for the future perspective of precisely measuring the Higgs self-couplings. In this talk, we will present our work on the leading two-loop corrections to the trilinear Higgs couplings in the two-Higgs-doublet model (THDM) and other models beyond the SM. We focus in particular on the couplings hhh, hhH , which are the most important for di-Higgs production at the (HL-)LHC. We will discuss the technical details of the calculation, in particular concerning the renormalization of the alignment limit, and briefly illustrate the phenomenological impact of our results.

Speaker: Alain Verduras Schaeidt (DESY)

KUTS25 (2).pdf

12:30 Lunch

For payment you need to obtain a guest card at the info desk of the canteen (located in the ground floor of the canteen). It costs a deposit of 7EUR and needs to be charged (can be charged using cash, Visa or Debit card). You should get back the deposit and the left-over amount at return.

8 Generic two-loop results for trilinear and quartic scalar self-interactions

Speaker: Martin Gabelmann (DESY)

slides.pdf

9 Two-loop BSM corrections to h->gammagamma in a triplet extension of the SM

Speaker: Pietro Slavich (LPTHE Paris)

Triplet.pdf

16:30 Coffee

10 Update on Higgs mass calculation with FlexibleEFTHiggs ( cancelled :( )

FlexibleEFTHiggs is a hybrid method for the calculation of the SM-like Higgs mass in SUSY-models and is implemented in the spectrum generator FlexibleSUSY. This talk will include a recap of the method and some of its subtleties like the usage of the full-model parametrization in the calculation. The recent modifications of FlexibleEFTHiggs will be presented like the inclusion of 3-loop QCD matching corrections in the calculation of the Higgs mass in the NMSSM. Also, some new analyses and parameter scans will be shown.

Speaker: Johannes Wünsche

11 Confronting a Standard Model extension with a dark $U(1)$ gauge sector with the prediction for the $W$-boson mass

Speaker: Heidi Angelika Rzehak

KUTS2025.pdf

20:00 Dinner (self-paid)

https://maps.app.goo.gl/L5qJCJYBR2TsKgB38

Wednesday 9 April

12 Interference effects in extended Higgs sectors (online)

Speaker: Georg Ralf Weiglein (Deutsches Elektronen-Synchrotron (DE))

KUTS_interfer_25.pdf

10:30 Coffee

13 Discussion on the future of KUTS