Séminaire / Seminar GReCO |
| « Constraining Axion-U(1) Inflation with Lattice Simulations » |
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Drew Jamieson |
| Inflationary models where the inflaton is an axion-like field coupled to gauge fields give rise to a rich phenomenology, including modifications to the primordial power spectrum, non-Gaussianity, parity violation, and gravitational waves. In this talk, I will present new results from lattice simulations of an axion–U(1) inflation model with an alpha-attractor potential. This potential leads to a significantly blue-tilted correction to the primordial power spectrum at small scales, which is tightly constrained by CMB observations. The leading-order non-Gaussianity is dominated by a blue-tilted equilateral bispectrum, which is similarly constrained by current CMB bispectrum analyses. I will present the simulation predictions for these observables and discuss the resulting bounds on the axion–gauge coupling strength derived from the absence of a bispectrum signal. Finally, I will outline the observable targets motivated by this model that could be strongly constrained—or potentially ruled out—by upcoming CMB and large-scale structure experiments. |
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lundi 5 mai 2025 - 11:00 Salle des séminaires Évry Schatzman Institut d'Astrophysique de Paris |
| Pages web du séminaire / Seminar's webpage |