Missing mass spectroscopy of Λ hypernuclei using the (e,e′K+) reaction has been performed at the Thomas Jefferson National Accelerator Facility (JLab) with several experiments in the past in Hall A and Hall C.
One experiment, expected to run in 2026 in Hall C, will provide the first study of the isospin dependence in medium-mass hyperisotopes by populating Λ-K-40 and Λ-K-48 using an isotopically enriched calcium target [JLab E12-15-008]. In the same campaign, it will be possible to study Λ interactions in nuclear matter using a lead target [JLab E12-20-013]. Further solid-state targets such as aluminum are also considered for this campaign.
The high-resolution spectrometers together with thin target foils and high beam currents guarantee an energy resolution on the sub-MeV level, much better than in hadron beam experiments.
The measurement of precise and accurate energy spectra of different hyperisotopes probes the Λ-N interaction in nuclei including the Λ-N-N three-body force. The latter is assumed to play a key role for the stiffness of the nuclear equation-of-state relevant for the stability of neutron stars.
(On behalf of JLab Hypernuclear Collaboration)