Making carbon in stars

The triple alpha (3α) process plays an important role in the production of C in stars. Its rate is known with an accuracy of about 12%. We examine the corresponding uncertainties introduced in the description of pre-supernova stars, of nucleosynthesis in a core-collapse SN explosion, and of the production of C during the third dredge-up in asymptotic giant branch (AGB) stars. For the AGB case we consider also the effects of uncertainties in the N(p, γ)O rate. We conclude that the present accuracy of the 3α rate is inadequate and describe new experiments that will lead to a more accurate value.