Ljubljana Summer School on Particle Physics and Cosmology

Session

Poster session

29 Aug 2023, 19:00

Faculty for mathematics and physics

28. LHC tau-pair production constraints on $a_τ$ and $d_τ$

Joachim Weiss

29/08/2023, 19:00

Poster

We point out that relevant constraints on the anomalous magnetic ($a_τ$) and electric ($d_τ$) moment of the tau lepton can be derived from tau-pair production measurements performed at the LHC. Our conclusion is based on the observation that the leading relative deviations from the Standard Model prediction for $pp \to τ^+ τ^−$ due to $a_τ$ and $d_τ$ are enhanced at high energies. Less precise...

29. The shift-invariant orders of an ALP

Jonathan Kley (DESY)

29/08/2023, 19:20

Poster

Usually, effective field theories (EFTs) for axion-like particles (ALPs) are built assuming a shift symmetry for the ALP due to the global U(1) Peccei-Quinn (PQ) symmetry that is at the heart of the axion mechanism. However, it is generally believed that global symmetries, in particular axion shift symmetries, can only be approximate. Therefore, it is important to include shift-breaking...

30. An updated view on the Atomki anomalies

Claudio Toni (Università degli studi di Roma La Sapienza)

29/08/2023, 19:40

Poster

In view of the latest experimental results recently released by the ATOMKI collaboration, we critically re-examine the possible theoretical interpretation of the observed anomalies in terms of a new BSM boson X with mass ∼ 17 MeV. Employing a multipole expansion method, we estimate the range of values of the nucleon couplings to the new light state in order to match the experimental...

31. Investigating new physics in $\tau-\mu$ sector via LFU ratios $R_K^{\tau \mu}$ and $R_{K^*}^{\tau \mu}$

Ms NEETU RAJ SINGH CHUNDAWAT (Indian Institute of Technology, Jodhpur, India)

29/08/2023, 20:00

Poster

We explore the potential of the ratios $R^{\tau \mu}$ in the decays $B \to K \ell \ell$ and $B \to K^* \ell \ell$ ($\ell=\mu,\tau$) as a means to probe new physics effects within the $\tau-\mu$ sector.We find that these ratios deviate from their SM predictions even for universal couplings. This indicates that the observed deviation of these ratios from their SM predictions alone is...

32. New tests of short-distance dynamics in $b\to s \bar{\ell} \ell$ decays

Arianna Tinari (University of Zürich)

29/08/2023, 20:20

Poster

The rare $B \to K^{(*)} \bar{\ell} \ell$ decays exhibit a long-standing tension with Standard Model (SM) predictions, which can be attributed to a lepton-universal short-distance $b \to s \bar{\ell} \ell$ interaction.
We present two novel methods to disentangle this effect from long-distance dynamics: one based on the determination of the inclusive $b \to s \bar{\ell} \ell$ rate at high...

33. NNLO+PS event generation for $p p \rightarrow Z h$ with contributions from electroweak SMEFT operators

Luc Schnell

29/08/2023, 20:40

Poster

The associated production of a Higgs boson, i.e. $p p \rightarrow Z h$, allows for precise measurements of the Higgs boson couplings. In particular, $Z h$ with $Z \rightarrow \ell^{+} \ell^{-}$and $h \rightarrow b \bar{b}$ is the most sensitive channel for detecting $h \rightarrow b \bar{b}$ decays at the LHC. It will be probed extensively in future LHC runs. We present a comprehensive...