New measurement of the Hoyle state radiative transition width

• DOI: 10.1016/j.physletb.2024.139083
• Publication Date: 2024-10-18T13:58:18Z
• Authors: T.K. Rana; Deepak Pandit; S. Manna; Samir Kundu; K. Banerjee; A. Sen; R. Pandey; G. Mukherjee; T.K. Ghosh; S.S. Nayak; R. Shil; P. Karmakar; K. Atreya; K. Rani; D. Paul; R. Santra; A. Sultana; S. Basu; S. Pal; S. Sadhukhan; Debasish Mondal; S. Mukhopadhyay; Srijit Bhattacharya; Surajit Pal; P. Pant; Pratap Roy; Sk M. Ali; S. Mondal; A. De; Balaram Dey; R. Datta; S. Bhattacharya; C. Bhattacharya
• Keywords: Inelastic scattering; Radiative decay of Hoyle state; Complete kinematics reaction; 12C(p,p)12C reaction; Physics; QC1-999; 0103 physical sciences; The Hoyle state decay; 01 natural sciences

The radiative decay of the Hoyle state serves as the gateway to the production of heavier elements in a stellar environment. Here, we present an exclusive measurement of electric quadruple (E2) transitions of the Hoyle state to the ground state of 12C through the 12C(p, p′γγ)12C reaction. A triple coincidence measurement yields the radiative branching ratio Γrad/Γ = 4.01 (30) × 10−4. This result was corroborated by an independent experiment based on the complete kinematical measurement via 12C(p, p′)12C reaction, yielding a consistent result of Γrad/Γ = 4.04 (30) × 10−4. Combining our results with the currently adopted values of Γπ(E0)/Γ and Γπ(E0), the radiative width of the Hoyle state is determined to be 3.75 (40) × 10−3 eV. It is important to note that our finding do not align with a recently reported 34% increase in the radiative decay width of the Hoyle state but is consistent with the currently accepted value.