Breakup of 8B and the S17 astrophysical factor reexamined

نویسندگان

  • L. Trache
  • F. Carstoiu
  • C. A. Gagliardi
  • R. E. Tribble
چکیده

Existing experimental data for the breakup of 8B at energies from 30 to 1000 MeV/nucleon on light through heavy targets are analyzed in detail in terms of an extended Glauber model. The predictions of the model are in excellent agreement with independent reaction data (reaction cross sections and parallel momentum distributions for corelike fragments). Final-state interactions have been included in the Coulomb dissociation component. We extract asymptotic normalization coefficients (ANC) from which the astrophysical factor S17s0d for the key reaction for solar neutrino production, 7Besp ,gd8B, can be evaluated. Glauber model calculations using different effective interactions give consistent, though slightly different results. The differences give a measure of the precision one can expect from the method. The unweighted average of all ANCs extracted leads to S17s0d=18.7±1.9 eV b. The results of this new analysis are compared with the earlier one. They are consistent with the values from most direct measurements and other indirect methods.

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تاریخ انتشار 2004