¹⁴Be$(p,n)$¹⁴B reaction at 69 MeV in inverse kinematics

Abstract

A Gamow–Teller (GT) transition from the drip-line nucleus ¹⁴Be to ¹⁴B was studied via the $(p,n)$ reaction in inverse kinematics using a secondary ¹⁴Be beam at 69 MeV/nucleon. The invariant mass method is employed to reconstruct the energy spectrum. A peak is observed at an excitation energy of 1.27(2) MeV in ¹⁴B, together with bumps at 2.08 and 4.06(5) MeV. The observed forward peaking of the state at 1.27 MeV and a good description for the differential cross section, obtained with a DWBA calculation provide support for the $1^{+}$ assignment to this state. By extrapolating the cross section to zero momentum transfer the GT-transition strength is deduced. The value is found to compare well with that reported in a β-delayed neutron emission study.