Constraining the electron-capture rates of neutron rich nuclei with (d,²He) reaction in inverse kinematics.

Nuclear charge-exchange reactions can be used to estimate the electron-capture rates which are key quantities in a variety of astrophysical scenarios. Over the past decades, great progress has been made to constrain electron-capture rates on stable nuclei by using reactions in forward kinematics. However, the unstable neutron-rich nuclei capturing the most during, for example, the core-collapse supernovae, remained inaccessible. Recently a (d,²He) charge-exchange reaction in inverse kinematics with the Active-Target Time-Projection Chamber and the S800 Spectrograph was developed at NSCL, for extracting Gamow-Teller strengths in the β+ direction on unstable nuclei. This makes it possible, for the first time, to constrain electron-capture rates on neutron-rich nuclei. In this talk I will discuss recent results of the pilot ¹⁴O(d,²He) experiment.