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 HAL : in2p3-00024273, version 1
 Physics Letters B 615 (2005) 167-174
 $^{16}$O Coulomb dissociation: towards a new means to determine the $^{12}$C+$\alpha$ fusion rate in stars
 (2005)
 A feasibility study was made of an important aspect of the Coulomb-dissociation method, which has been proposed for the determination of the rate of the astrophysically important $^{12}C(\alpha, \gamma)^{16}O$ reaction. A crucial aspect is the disentanglement of nuclear and Coulomb interactions on one hand and the separation of dipole and quadrupole contributions on the other. As a first step the resonant breakup via two well-known 2$^+$ states of $^{16}O$ was measured. The differential cross section of $^{208}Pb(^{16}O, ^{16}O*)^{208}Pb$ and the angular correlations of the fragments $^{12}C$ and $\alpha$ in the center of mass were measured and compared to theoretical predictions calculated in DWBA and the coupled-channel method. The best agreement was found for the state at 11.52 MeV associated to a one-step excitation from the ground state, while the 9.84 MeV requires coupling to the first-excited 2$^+$ state and is not well described.
 Thème(s) : Physique/Physique Nucléaire Expérimentale
 in2p3-00024273, version 1 http://hal.in2p3.fr/in2p3-00024273 oai:hal.in2p3.fr:in2p3-00024273 Contributeur : Suzanne Robert <> Soumis le : Lundi 20 Juin 2005, 16:16:52 Dernière modification le : Samedi 1 Octobre 2005, 15:37:33