Speaker
Description
The $^{12}$C+$^{12}$C fusion reaction is an important pathway for the synthesis of elements with mass A$\geq$20 and for the later stages of stellar evolution. Information on cross-section of $^{12}$C+$^{12}$C reaction below E$_{cm}$ = 2.2 MeV is sparse and previous measurements reported by different groups exhibit substantial inconsistencies. A new measurement of this reaction has been performed directly via $\gamma$-rays detection within the LUNA experiment at the Bellotti Ion Beam Facility (BIBF), located in the deep underground laboratory of Gran Sasso National Laboratory. The background intrinsic to the detection methods causes a significant uncertainty in the measured cross-section at sub barrier energies. Therefore, background reduction using both active and passive shielding is necessary. In this campaign, the $\gamma$-rays were detected using a high-efficiency (150$\%$), high-resolution HPGe detector, paired with two large-volume NaI(Tl) annulus detectors, each divided into eight sections. The entire detection system is enclosed by passive shielding consisting of 25 cm of lead and 1 cm of copper. Here, we present our detailed detector characterization leading to a major reduction in target contamination. The experimental spectra were benchmarked against GEANT4 simulations, validating the detection setup and enabling us to present the first preliminary results of our direct reaction cross-section
measurements.