Kibédi, T.Stuchbery, A. E.Dracoulis, G. D.Robertson, K. A.2025-12-172025-12-172101-6275ORCID:/0000-0002-9205-7500/work/160797536ORCID:/0000-0002-0198-9901/work/162367336https://hdl.handle.net/1885/733795942The triple-alpha process leading to the formation of stable carbon in the Universe is one of the most important nuclear astrophysical processes. The radiative width of the so-called Hoyle state, involving the 7.654 MeV E0 and the 3.2148 MeV E2 transitions, is known with 10-12% accuracy. A novel, more direct approach to determining the width is proposed here, based on the measurement of the E0 and the E2 internal pair conversion intensities. We report on the development of a new magnetic pair spectrometer with high sensitivity for electron-positron pairs and with excellent energy resolution.en201210.1051/epjconf/2012350600184883012270