Beschreibung
Particle production is common to many microphysical models of inflation and can imprint observable features in the cosmic microwave background (CMB) anisotropies. Based on arxiv: 2606.26823, 2509.23123, we consider a scenario in which the inflaton couples to an extremely massive field ($m_\chi \gtrsim \mathcal{O}(100 H_I)$, where $H_I$ is the inflationary Hubble scale). In this model, particle production happens in a burst at a characteristic conformal time, $\eta_*$, which sources localised features in the CMB. We explore these localised features both through a position space search, adapting techniques from thermal Sunyaev-Zeldovich (tSZ) cluster finding, to search Planck data, and through a more conventional power spectrum analysis, computing the full contribution to the power spectrum, and searching for these features in Planck and Atacama Cosmology Telescope (ACT) data. From here we put bounds on the underlying inflationary model, and compare the constraining power of the two methods.