Comunicazione
Investigating deuterium destruction in BBN with the Felsenkeller accelerator.
Sreekala A.R., Caciolli A., Bemmerer D., Broggini C., Bruno C.G., Campostrini M., Corvisiero P., Depalo R., Ferraro F., Glorius J., Lossin T., Masha E., Menegazzo R., Piatti D., Rigato V., Skowronski J., Zavatarelli S.
The $^{2}H(p, \gamma)^{3}He$ reaction is the dominant process responsible for the destruction of deuterium during the Big Bang Nucleosynthesis(BBN) that changes the primordial deuterium abundance ratio (D/H). D/H ratio can be measured through direct observations at high precision, but theoretical models come up short due to lack of precise measurements of reaction cross-sections over the whole energy range. In this study, we perform the reaction at the Felsenkeller Underground facility at 5--10 $\mu$A, 400 keV to 2 MeV energy using two deuterated targets $ZrD_2$ and TiD and measure the gamma rays produced with 6 germanium detectors at different angles. The cross-section is measured over a range of energies that covers the low-energy LUNA Collaboration data, too, enabling a comparison through independent setups to reduce uncertainties on the final cross-section. The efficiency of the detectors is calibrated using 4 radioactive sources ($^{88}Y$, $^{137}Cs$, $^{60}Co$ and $^{22}Na$) which covers up to 1.8 MeV, and then extended to higher energies using $^{27}Al(p, \gamma)^{28}Si$. The detector setup also allows a study on the angular distribution of the cross-sections.