Angular Distribution Of Tritons Research Articles

Evidence of E1 excited states in 19F from the (γ, t) reaction

The 19F(γ, t) 16O reaction was studied over an energy region of 18 to 23 MeV. Two resonances were observed at 18.8 MeV and 20.1 MeV. The angular distribution of tritons from these resonances indicated that the tritons are emitted predominantly in a p-wave, implying j π = 1 2 −, or 3 2 − with T = 1 2 for both levels. A comparison with other experiments i the states could be attributed to 16O+t cluster configurations. In addition, from the measured ratio σ(γ, α)/σ(γ, t) ⪅ 0.01 it is concluded that the formation of 15N+α cluster states is small in this region of excitation.

The (d, t) Reactions on N=50 Nuclei

Angular distribution of tritons in (d, t) reactions induced by 21.4 MeV deuterons on 88 Sr, 89 Y, 90 Zr and 92 Mo targets was measured to obtain the l -values and the spectroscopic factors of transitions. In the reaction on 88 Sr, all of the expected spectroscopic strengths for T < states are found for the transitions leading to 1g 9/2 , 2p 1/2 , 2p 3/2 , and 1f 5/2 shell-model states. In contrast with this situation, severe fragmentation of the strength as a function of proton numbers was found in the other isotones. Any apparent spectra for 1f 7/2 neutron shell-model orbit have not been observed so characteristic as for 1g 9/2 , 2p 1/2 , 2p 3/2 or 1f 5/2 orbits. The shell-model forbidden l =2 transitions to (2d 5/2 ) -1 states were observed in the 89 Zr and 91 Mo nuclei. From these strengths the amount of shell-model impurities in the ground-state correlation of the target N =50 nuclei is estimated as a function of proton numbers.

Angular distribution of tritons from the 11B(n, t) 9Be reaction at 14.4 MeV

The angular distribution of tritons from the (n, t) reaction on 11B has been measured at the neutron bombarding energy of 14.4 MeV. The results obtained have been compared with the DWBA predictions. The shape of the (n, t) angular distribution is reasonably well reproduced by the DWBA calculations, while the absolute values are in disagreement.

Energy Levels ofAu195

The energy levels of ${\mathrm{Au}}^{195}$ were studied by observation of conversion electrons following the ($p,2n$) reaction on ${\mathrm{Pt}}^{196}$, and by measurement of the energy spectrum and angular distribution of tritons from the ${\mathrm{Au}}^{197}(p,t)$ reaction. Many new energy levels are reported, and several new $I\ensuremath{-}\ensuremath{\pi}$ assignments are made by combining information from the two experiments.

A study of (n, d) and (n, t) reactions on 7Li

Charged-particle spectra from neutron irradiation of 7Li were measured at several angles. The angular distribution of deuterons from the 7Li(n, d) 6He(g.s.) transition was compared with the DWBA prediction. The absolute value of the cross section was in satisfactory agreement, but the shape of the measured angular distribution was not well reproduced by the calculations. The angular distribution of tritons in the peak of the spectra was compared with the DWBA prediction for the pickup of two nucleons. The shape of the angular distribution was reproduced reasonably well. A discrepancy in the absolute value was interpreted as a consequence of quasi-free n-t scattering.

Study of states in 16O by the reaction 15N( τ, d) 16O

Angular distributions of deuterons emitted in the reaction 15N( τ, d) 16O at E τ = 11 MeV were measured for transitions to 18 states. DWBA fits were made and spectroscopic factors extracted, where possible. The results are in many cases in agreement with recent theoretical predictions; some discrepancies are discussed. Also the angular distribution of tritons from the reaction 15N( τ, t 0) 15O was measured.

Angular distribution of tritons from the reaction B 10+n at 14.4 MeV

The angular distributions of tritons from the reactions B 10(n, t)Be g.s. 8 and B 10(n, t)Be 2.9 MeV 8 have been measured. Both angular distributions have two pronounced maxima, one at small angles and the other at about 80°. This indicates that the reaction proceeds via the direct interaction mechanism. The Butler theory fits the first maximum in the B 10(n, t)Be g.s. 8 angular distribution quite well. The deformation of Be 8 and B 10 nuclei makes the analysis more difficult, since higher values for the total angular momentum of the transferred deuteron are allowed. There is no possibility of distinguishing between the pickup (n, t) and the sequential pickup (n-d-t). The plane wave theory does not give a satisfactory explanation of the angular distribution of tritons from the reaction B 10(n, t)Be 2.9 MeV 8.

Distribution angulaire des tritons émis dans la réaction 6Li(n,t) 4He (1)

The angular distribution of tritons emitted in the /sup 6/Li(n,t)/sup 4/ He reaction is measured for E/sub n/= 190 kev. The tritons are detected with photographic plates placed around the /sup 6/Li target. The angular distribution obtained is not symmetric backward-forward. (auth)

The Theory of (d, t) Reactions

Expressions for the angular distribution of tritons emitted from nuclei bombarded with deuterons have been obtained using Born's approximation and the non-perturbation method of Butler. Discussion of the effect of different forms of the triton wave function on the angular distribution is given. The theory is shown to explain the experimental angular distributions satisfactorily.