Key measurements at the future electron-ion collider (EIC), including first-of-their-kind studies of kaon structure, require the detection of ${\mathrm{\Lambda }}^0$ at forward angles. We present a feasibility study of ${\mathrm{\Lambda }}^0\to n{\pi }^0$ measurements using a high-granularity zero-degree calorimeter to be located about 35 m from the interaction point. We introduce a method to address the unprecedented challenge of identifying ${\mathrm{\Lambda }}^0\mathrm{s}$ with energy $O(100)\mathrm{GeV}$ that produce displaced vertices of $O(10)\mathrm{m}$. In addition, we present a reconstruction approach using graph neural networks. We find that the energy and angle resolution for ${\mathrm{\Lambda }}^0$ is similar to that for neutrons, both of which meet the requirements outlined in the EIC Yellow Report. Furthermore, we estimate performance for measuring the neutron’s direction in the ${\mathrm{\Lambda }}^0$ rest frame, which reflects the ${\mathrm{\Lambda }}^0$ spin polarization. We estimate that the neutral-decay channel ${\mathrm{\Lambda }}^0\to n{\pi }^0$ will greatly extend the measurable energy range for the charged-decay channel ${\mathrm{\Lambda }}^0\to p{\pi }^{-}$, which is limited by the location of small-angle trackers and the accelerator magnets. This work paves the way for EIC studies of kaon structure and spin phenomena.

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• Electron-ion collisions
• QCD in nuclear reactions
• Quantum chromodynamics