First experimental constraints on the interference of 32+ resonances in the F18(p,α)O15 reaction

K. Y. Chae, The University of Tennessee, Knoxville
D. W. Bardayan, ORNL Physics Division
J. C. Blackmon, ORNL Physics Division
D. Gregory, Tennessee Technological University
M. W. Guidry, The University of Tennessee, Knoxville
M. S. Johnson, Oak Ridge Associated Universities
R. L. Kozub, Tennessee Technological University
R. J. Livesay, Colorado School of Mines
Z. Ma, The University of Tennessee, Knoxville
C. D. Nesaraja, The University of Tennessee, Knoxville
S. D. Pain, Rutgers University–New Brunswick
S. Paulauskas, Tennessee Technological University
M. Porter-Peden, Colorado School of Mines
J. F. Shriner, Tennessee Technological University
N. Smith, Tennessee Technological University
M. S. Smith, ORNL Physics Division
J. S. Thomas, Rutgers University–New Brunswick


The interference effects among Jπ=3/2+ resonances in the F18+p system have not been previously measured. R-matrix calculations show that the cross sections above the Ec.m.=665 keV resonance are sensitive to the interference between the Ec.m.=8, 38, and 665 keV resonances. An excitation function for the H1(F18,α)O15 reaction has been measured in the energy range of Ec.m.=663-877 keV using radioactive F18 beams at the Holifield Radioactive Ion Beam Facility (HRIBF). By comparing the observed cross sections with the R-matrix calculations, we provide the first experimental constraints on the interference. Upper limits on proton widths (Γp) of the Ec.m.=827 and 842 keV resonances have been set as well. © 2006 The American Physical Society.