Fig. 3: Enhancement of the Hoyle radiative-width via neutron upscattering as a function of temperature.
From: Neutron-upscattering enhancement of the triple-alpha process

Contributions from upscattering to the 12C ground state (green dashed) and to the 12C first-excited state (black solid). The sum of these is shown in dotted blue for a neutron density of 106 g cm−3. The comparable contribution from protons as calculated in ref. 3 is shown by the dot-dashed red line.