The ${}_{}{}^{86}{}_{}{}^{}\mathrm{Kr}\mathrm{}(d,p)\mathrm{}{}_{}{}^{87}{}_{}{}^{}\mathrm{Kr}$ reaction leading to three strong low-lying states in ${}_{}{}^{87}{}_{}{}^{}\mathrm{Kr}(d_{\frac{5}{2}}\mathrm{g}.\mathrm{s}.\mathrm{}, 0.53 \mathrm{MeV}{s}_{\frac{1}{2}}, \mathrm{and} 1.47 \mathrm{MeV}{d}_{\frac{3}{2}})$ has been studied as a function of energy from 5.0 to 10.5 MeV at 100, 120, 140, and 160° laboratory angles. The strong, unusually shaped threshold cusp observed in the ${}_{}{}^{86}{}_{}{}^{}\mathrm{Kr}\mathrm{}(d,p)\mathrm{}{}_{}{}^{87}{}_{}{}^{}\mathrm{Kr}$($d_{\frac{5}{2}}$ g.s.) excitation curve near 7.56 MeV, threshold of the ${}_{}{}^{86}{}_{}{}^{}\mathrm{Kr}\mathrm{}(d,n)\mathrm{}{}_{}{}^{87}{}_{}{}^{}\mathrm{Rb}_{}^A{}_{}{}^{}$ ($d_{\frac{5}{2}}$ isobaric analog resonance) reaction, is discussed in terms of its position in a systematic study and classification of such threshold effects, using simple quantitative physical considerations. The ${}_{}{}^{86}{}_{}{}^{}\mathrm{Kr}$ data are fit with coupled-channel Born-approximation calculations.

• Received 9 April 1971

DOI:https://doi.org/10.1103/PhysRevC.4.836