Impact of theoretical uncertainties on model parameter reconstruction from gravitational wave signals sourced by cosmological phase transitions

26 Sept 2024, 16:46
16m
Main Auditorium (DESY Hamburg)

Main Auditorium

DESY Hamburg

Notkestr. 85 D-22607 Hamburg, Germany
Cosmology & Astroparticle Physics Parallel Thursday Cosmo 1

Speaker

Daniel Schmitt

Description

Different thermal resummation techniques impact the gravitational wave (GW) spectra from cosmological first-order phase transitions predicted in a given particle physics model. To investigate this effect, we perform large-scale parameter scans of the electroweak phase transition (EWPT) in the dynamical real-singlet extension of the Standard Model (SM) using three different perturbative approximations of the effective potential. While predictions of the GW amplitudes from the common, four-dimensional (4D) Daisy-resummed potentials are unreliable compared to state-of-the-art dimensionally reduced (3D) potentials, I will demonstrate that the overall detectable parameter spaces are robust up to a few percent in uncertainty. Regarding the reconstruction of the model parameters given a GW signal, I will illustrate that theoretical uncertainties however remain dominant over the experimental ones when using 4D standard techniques. Three-dimensional thermal effective theory, on the other hand, is accurate already at one-loop order, therefore providing the most promising route towards robust predictions for upcoming GW observatories.

Primary authors

Daniel Schmitt Laura Sagunski (Goethe University Frankfurt) Dr Marco Merchand Dr Marek Lewicki Philipp Schicho (Goethe University Frankfurt)

Presentation materials