We investigate a novel gravitational wave (GW) production mechanism from gravitons generated during the pre-thermal phase of cosmic reheating, where the energy density is dominated by non-thermalized inflaton decay products, dubbed reheatons. We consider multiple production channels, including: $i)$ pure inflaton-inflaton annihilation, $ii)$ graviton Bremsstrahlung from inflaton decay, $iii)$...
In this talk, I will summarize some of our efforts to interpret the GWB-like signal observed by the NANOGrav collaboration as inflationary gravitational waves, by sampling reheating temperature, tensor spectral index, and the running of the tensor spectral index. I will show that there is available parameter space to describe the signal, even if we impose constraints from CMB, LVK, and do not...
