S. Beceiro

Experimental study of the 15O(2p, γ)17Ne cross section by Coulomb Dissociation for the rp process

The time-reversed reaction O-15(2p, gamma) Ne-17 has been studied by the Coulomb dissociation technique. Secondary 17Ne ion beams at 500 AMeV have been produced by fragmentation reactions of Ne-20 in a beryllium production target and dissociated on a secondary Pb target. The incoming beam and the reaction products have been identified with the kinematically complete LAND-(RB)-B-3 experimental setup at GSI. The excitation energy prior to decay has been reconstructed by using the invariant-mass method. The preliminary differential and integral Coulomb Dissociation cross sections (sigma(Coul)) have been calculated, which provide a photoabsorption (sigma(photo)) and a radiative capture cross section (sigma(cap)). Additionally, important information about the nuclear structure of the Ne-17 nucleus will be obtained. The analysis is in progress.

Experimental study of the O-15(2p, gamma) Ne-17 cross section by Coulomb Dissociation for the rp process

The time-reversed reaction O-15(2p, gamma) Ne-17 has been studied by the Coulomb dissociation technique. Secondary 17Ne ion beams at 500 AMeV have been produced by fragmentation reactions of Ne-20 in a beryllium production target and dissociated on a secondary Pb target. The incoming beam and the reaction products have been identified with the kinematically complete LAND-(RB)-B-3 experimental setup at GSI. The excitation energy prior to decay has been reconstructed by using the invariant-mass method. The preliminary differential and integral Coulomb Dissociation cross sections (sigma(Coul)) have been calculated, which provide a photoabsorption (sigma(photo)) and a radiative capture cross section (sigma(cap)). Additionally, important information about the nuclear structure of the Ne-17 nucleus will be obtained. The analysis is in progress.

Coulomb breakup of 17 Ne from the view point of nuclear astrophysics

By the Coulomb breakup of 17Ne, the time-reversed reaction 15O(2p,γ)17Ne has been studied. This reaction might play an important role in the rp process, as a break-out reaction of the hot CNO cycle. The secondary 17Ne ion beam with an energy of 500 MeV/nucleon has been dissociated in a Pb target. The reaction products have been detected with the LAND-R3B experimental setup at GSI. The preliminary differential and integral Coulomb dissociation cross section sCoul has been determined, which then will be converted into a photo-absorption cross section sphot o, and a two-proton radiative capture cross section σcap. Additionally, information about the structure of the 17Ne, a potential two-proton halo nucleus, will be received. The analysis is in progress.

Coulomb dissociation reactions on proton-rich Ar isotopes

The dipole strength response of neutron-deficient Argon isotopes was investigated in a Coulomb dissociation experiment using the LAND setup at GSI. Especially the study of low-lying strength components is interesting in several respects. Recent RQRPA calculations predict the appearance of low-lying E1 strength at excitation energies of Ex ≈ 9 MeV for nuclei at the proton dripline in this mass region [1, 2]. In a macroscopic picture, this is discussed in the context of an out-of-phase oscillation of a thin proton skin against the isospin-saturated core. For nuclear astrophysics the measured (γ, p) reactions are interesting for the calculation of reaction cross-sections and radiative proton capture rates for the rp-process. In this hydrogen burning process a lot of nuclear structure information is still missing, for instance for the bottleneck nuclei S and Ar [3].

Coulomb Dissociation of 27 P

The 26Al nucleus has a shorter life‐time than the Universe showing that the nucleosynthesis of this element might be an ongoing process in stars. The reaction 26Si(p,γ)27 P competes with the production of 26Al. Coulomb dissociation of 27 P is an indirect method to measure that reaction. An experiment was performed at GSI with a 36Ar primary beam at 500 MeV to measure this reaction.

Coulomb dissociation of 27P

The 26Al nucleus has a shorter life‐time than the Universe showing that the nucleosynthesis of this element might be an ongoing process in stars. The reaction 26Si(p,γ)27 P competes with the production of 26Al. Coulomb dissociation of 27 P is an indirect method to measure that reaction. An experiment was performed at GSI with a 36Ar primary beam at 500 MeV to measure this reaction.