A new direct measurement of the absolute cross section of the 'H(Be-7,gamma)B-8 reaction has been performed in inverse kinematics at E-cm = 990 keV. A radioactive Be-7 beam (E-lab = 8 MeV) and a windowless H-2 gas target were used; B-8 recoils were identified and counted by a recoil mass separator. The reaction cross section was derived by normalization to the elastic scattering cross section, measured in a separate run. The resulting value sigma (r) = 0.40 +/- 0.12 mub yielded an astrophysical S-factor at zero energy S-0 = 15.3 +/- 4.5 eV b, in fair agreement with recommended values.
Direct measurement of the absolute cross section of p(7Be,γ)8B / F., Terrasi; L., Gialanella; Imbriani, Gianluca; F., Strieder; L., Campajola; A., D'Onofrio; U., Greife; G., Gyurky; C., Lubritto; A., Ordine; Roca, Vincenzo; C., Rolfs; Romano, Mario; D., Rogalla; C., Sabbarese; E., Somorjai; H. P., Trautvetter. - In: NUCLEAR PHYSICS. A. - ISSN 0375-9474. - STAMPA. - 688:(2001), pp. 539-542. [10.1016/S0375-9474(01)00781-3]
Direct measurement of the absolute cross section of p(7Be,γ)8B
IMBRIANI, GIANLUCA;ROCA, VINCENZO;ROMANO, MARIO;
2001
Abstract
A new direct measurement of the absolute cross section of the 'H(Be-7,gamma)B-8 reaction has been performed in inverse kinematics at E-cm = 990 keV. A radioactive Be-7 beam (E-lab = 8 MeV) and a windowless H-2 gas target were used; B-8 recoils were identified and counted by a recoil mass separator. The reaction cross section was derived by normalization to the elastic scattering cross section, measured in a separate run. The resulting value sigma (r) = 0.40 +/- 0.12 mub yielded an astrophysical S-factor at zero energy S-0 = 15.3 +/- 4.5 eV b, in fair agreement with recommended values.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
