This book focuses on a new determination of the radiative width, rad of the Hoyle state from the observation of proton-gamma-gamma triple coincidences using the 12C (p, p' )12C reaction at 10.7 MeV bombarding energy. The angular correlation of the cascading 3.215 MeV and 4.439 MeV Gamma-rays corresponding to the 0+ 2 - 2+ 1 - 0+ 1 transitions in 12C was also measured for the first time, which uniquely confirms a spin and parity of 0+ for the Hoyle state. The two Gamma-rays from the Hoyle state were studied in coincidence with inelastically scattered protons using the CACTUS and SiRi arrays at the Oslo Cyclotron Laboratory.