Journal Club

Seminar Room

Monday 25th of May, 2026

Hour: 12:00

Title: When Two Loops Matter: Electroweak Precision in the SMEFT

Presented by: Chiara Giuliano

Ref: https://arxiv.org/abs/2604.26817

Abstract:

We identify a novel next-to-leading order renormalization effect in the dimension-six SMEFT with direct phenomenological impact. The Higgs-Yukawa operator that modifies the top-Higgs coupling κt induces a shift in the W mass at two-loop order through a large anomalous dimension, rendering electroweak precision observables a powerful indirect probe of κt. We show that this effect is essential for the consistent interpretation of data from future Tera-Z and Giga-W factories such as FCC-ee. The effect is realized in a simple renormalizable two-Higgs doublet model.

Hour: 12:30

Title: Probing the Kinematic Dipole with LISA: an analytical treatment

Presented by: Andrii Dashko

Ref: https://arxiv.org/pdf/2604.08968

Abstract:

The motion of the Solar System with respect to the cosmic rest frame induces a kinematic dipole
in the stochastic gravitational-wave background (GWB). Detecting this signal with space-based
interferometers would provide an independent measurement of our peculiar velocity and a GW
probe of cosmic anisotropies. We present a fully analytic derivation of the response of the Laser
Interferometer Space Antenna (LISA) to a kinematic dipole, and construct an optimal estimator
for its detection. We show that the dipolar response is governed by a single frequency-dependent
function fixed by symmetry, and we compute its behaviour across the LISA band. Using Fisher
forecasts, we find that for a scale-invariant background detectability requires h^2ΩGW ≳ 5 × 10−8
for fiducial LISA, and h^2ΩGW ≳ 5 × 10−10 for a detector with characteristic instrumental-noise
amplitudes improved by an order of magnitude. Prospects are more favorable for signals with richer
frequency profile. We also explore the potential of the kinematic dipole to break degeneracies,
particularly in the presence of strong galactic foregrounds or noise features that closely mimic the
primordial signal.