Neutron-upscattering enhancement of the triple-alpha process

The neutron inelastic scattering of carbon-12, populating the Hoyle state, is a reaction of interest for the triple-alpha process. The inverse process (neutron upscattering) can enhance the Hoyle state’s decay rate to the bound states of ¹²C, effectively increasing the overall triple-alpha reaction rate. The cross section of this reaction is impossible to measure experimentally but has been determined here at astrophysically-relevant energies using detailed balance. Using a highly-collimated monoenergetic beam, we measured neutrons incident on the Texas Active Target Time Projection Chamber (TexAT TPC) filled with CO₂ gas, measuring the 3α-particles (arising from the decay of the Hoyle state following inelastic scattering) and a cross section was extracted. The results of this recently-published work will be discussed.