$(d,n)$ proton-transfer reactions on ${}^9\mathrm{Be}, {}^{11}\mathrm{B}, {}^{13}\mathrm{C}, {}^{14,15}\mathrm{N}$, and ${}^{19}\mathrm{F}$ and spectroscopic factors at $E_d=16\mathrm{MeV}$

The $(d,n)$ reaction has been studied with targets of ${}^9\mathrm{Be}, {}^{11}\mathrm{B}, {}^{13}\mathrm{C}, {}^{14,15}\mathrm{N}$, and ${}^{19}\mathrm{F}$ at $E_d=16\mathrm{MeV}$ using a deuterated liquid-scintillator array. Advanced spectral unfolding techniques with accurately measured scintillator response functions were employed to extract neutron energy spectra without the need for long-path neutron time-of-flight. An analysis of the proton-transfer data at forward angles to the ground states of the final nuclei, using finite-range distorted-wave Born approximation analysis with common bound-state, global, and local optical-model parameter sets, yields a set of self-consistent spectroscopic factors. These are compared with the results of several previous time-of-flight measurements, most done many years ago for individual nuclei at lower energy and often analyzed using zero-range transfer codes. In contrast to some of the earlier published data, our data generally compare well with simple shell-model predictions, with little evidence for uniform quenching (reduction from shell-model values) that has previously been reported from analysis of nucleon knock-out reactions. Data for low-lying excited states in ${}^{14}\mathrm{N}$ from ${}^{13}\mathrm{C}(d,n)$ also is analyzed and spectroscopic information relevant to nuclear astrophysics obtained. A preliminary study of the radioactive ion beam induced reaction ${}^7\mathrm{Be}(d,n), E\left({}^7\mathrm{Be}\right)=30\mathrm{MeV}$ was carried out and indicates further improvements are needed for such measurements, which require detection of neutrons with $E_n<2\mathrm{MeV}$.

Figure 1

The experimental setup used in the $(d,n)$ measurements. The array of $4\times 6$ EJ315 detectors is shown positioned with the detector entrance windows 1 m from the target.

Figure 2

Light-response spectrum from the $d+{\left[{\mathrm{C}}_2{\mathrm{D}}_4\right]}_n$ reaction at ${10}^{\circ }$ (lab) and incident $E_d=16\mathrm{MeV}$ in electron-equivalent energy units. The software threshold is indicated.

Figure 3

Unfolded neutron energy spectrum from the $d+{\left[{\mathrm{C}}_2{\mathrm{D}}_4\right]}_n$ reaction at ${10}^{\circ }$ (lab) and incident $E_d=16\mathrm{MeV}$ (Fig. 2). The offline software threshold is indicated.

Figure 4

Light-response spectrum (top) and unfolded neutron energy spectrum (bottom) from the ${}^{13}\mathrm{C}\left(d,n\right){}^{14}\mathrm{N}$ reaction at ${20}^{\circ }$ (lab) and $E_d=16\mathrm{MeV}$. The offline software threshold is indicated. Known states in ${}^{14}\mathrm{N}$ are indicated by their excitation energy, spin, and parity (see text).

Figure 5

Light-response spectrum (top) and unfolded neutron energy spectrum (bottom) from the ${}^{14}\mathrm{N}\left(d,n\right){}^{15}\mathrm{O}$ reaction at $5^{\circ }$ (lab) and incident $E_d=16\mathrm{MeV}$. The offline software threshold is indicated.

Figure 6

Deuteron elastic scattering optical-model calculations (using global, modified global, and local OMPs compared with various published $(d,d)$ elastic scattering data sets [16], displayed as ratio to Rutherford scattering.

Figure 7

Measured ${}^9\mathrm{Be}\left(d,n\right){}^{10}\mathrm{B}$(g.s.) cross section compared to the $n$-ToF data of Park et al., from 1973 [23]. FR-DWBA calculations with global and local OMPs also are shown.

Figure 8

Measured ${}^{11}\mathrm{B}\left(d,n\right){}^{12}\mathrm{C}$(g.s.) cross sections compared with a FR-DWBA calculation using global OMPs.

Figure 9

Measured ${}^{13}\mathrm{C}\left(d,n\right){}^{12}\mathrm{N}$(g.s.) differential cross sections compared with a FR-DWBA calculation using global OMPs.

Figure 10

Measured ${}^{14}\mathrm{N}\left(d,n\right){}^{15}\mathrm{O}$(g.s.) differential cross sections compared with a FR-DWBA calculation using global OMPs.

Figure 11

Measured ${}^{15}\mathrm{N}\left(d,n\right){}^{16}\mathrm{O}$(g.s.) differential cross section compared with a FR-DWBA calculation using global OMPs.

Figure 12

Measured ${}^{19}\mathrm{F}\left(d,n\right){}^{20}\mathrm{Ne}$(g.s.) differential cross sections compared with a FR-DWBA calculation using global OMPs.

Figure 13

DSP-gated UM-DSA $d\left({}^7\mathrm{Be},n\right){}^8\mathrm{B}$ short-path $n$-ToF spectrum showing summed $(d,n)$ events near ${90}^{\circ }$ (lab), $E\left({}^7\mathrm{Be}\right)=30\mathrm{MeV}$.