Study of the $^{19}$O$(d,p)$ reaction in inverse kinematics with HELIOS*

The neutron single-particle components of states in $^{20}$O have been probed through the $(d,p)$ reaction in inverse kinematics. The experiment consisted of a 125 MeV radioactive $^{19}$O beam, produced by the ATLAS In-Flight facility at Argonne National Laboratory, impinging on a [(C$_{2}$D$_{4}$)$_{\rm n}$] target located inside the HELIcal Orbit Spectrometer (HELIOS). A Q-value resolution of $\sim150$~KeV was achieved for states in $^{20}$O. Absolute cross sections and angular distributions have been determined for a number of levels in $^{20}$O up to 7~MeV in excitation energy. A strong candidate for the previously unobserved $\ell=0$ $3^{+}$ level at 5.2~MeV has been identified. The extracted spectroscopic factors for $\ell=2$ (presumably $\nu0d_{5/2}$) and $\ell=0$ ($\nu1s_{1/2}$) transitions will be compared to those along the $Z=8$ isotopic chain and to microscopic calculations.