Neutron correlations in the 41K ground state and T = 1 2p-2h states in 40K

Differential cross sections have been measured for ⁴¹(d, t)⁴⁰K and ⁴¹K(p, d)⁴⁰K at 15 MeV using a magnetic spectrograph with electronic detection by proportional-counter-scintillator telescopes or semiconductor detectors. Knowledge of the structure of the ⁴⁰K multiplets ($\text{ν}\text{f}{}_{\mathrm{<mtext>7</mtext><mtext>2</mtext>}}\text{, π}\text{d}{}_{\mathrm{<mtext>3</mtext><mtext>2</mtext>}}{}^{\mathrm{?1}}$) and ($\text{ν}\text{p}{}_{\mathrm{<mtext>3</mtext><mtext>2</mtext>}}\text{, π}\text{d}{}_{\mathrm{<mtext>3</mtext><mtext>2</mtext>}}{}^{\mathrm{?1}}$) permits the determination of amplitudes and relative phases for various configurations and neutron correlations in the ⁴¹K ground state. Spectroscopic factors for neutron pick-up to states in ⁴⁰K are strongly influenced by the interference of transition amplitudes. In the (d, t) reaction T= 1, 2p-2h states are also observed.