{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"8ffb48f9ce879b1d67ae670cc5974f4a7236438a96635aa60e576faf9fa32aa7","created":"2026-10-03T07:18:07Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011","b0d27b024dda5c8e0cec401c72938e3b092a75c446fec39468840f6b4d022efb"],"salt":"a5e04859bb2dd2fc77f19353f63a5446801cdf8435110e2c1d547848d506514c","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"value","assisted_by":[],"external_id":"nuc.hypernuclei.lambda-potential-density","kind":"well-posed","literature_status":"open","n":"1","parents":[{"note":"","parent_revision":"b0d27b024dda5c8e0cec401c72938e3b092a75c446fec39468840f6b4d022efb","relation":"special_case"}],"plain":"Binding energies of $\\Lambda$ hyperons in heavy hypernuclei show that a $\\Lambda$ feels an attraction of about $30\\,\\mathrm{MeV}$ inside ordinary nuclear matter. Whether this attraction turns into repulsion at two to three times nuclear density decides whether Lambdas appear in neutron stars.","posed_since":"","precise":"Determine the Lambda single-particle potential $U_{\\Lambda}(n)$ in symmetric and pure neutron matter for n from $n_0\\ \\text{to}\\ 3n_0$ ($n_0=0.16\\ \\mathrm{fm}^{-3}$), given $U_{\\Lambda}(n_0)$ of about $-30\\ \\mathrm{MeV}$ from hypernuclear binding systematics. Answer: $U_{\\Lambda}(n)$ with quantified uncertainty from $\\Lambda N$ and $\\Lambda NN$ interactions constrained by hypernuclear binding energies, femtoscopic correlations and lattice QCD, and the resulting Lambda threshold density in beta-equilibrated matter.","problem_ref":null,"references":"","settled_by":"A $\\Lambda NN$ three-body force fixed by $p-p-\\Lambda$ and $d-\\Lambda$ femtoscopy and by binding energies of medium and heavy hypernuclei, used in quantum Monte Carlo or chiral many-body calculations of hyperonic matter.","status_note":"STAR reported the first deuteron-$\\Lambda$ correlation measurement at RHIC in 2025 (arXiv 2511.15493), a new constraint on the three-body sector.","title":"Density dependence of the $\\Lambda$ potential in nuclear matter","topic_ref":"b93128f3a78b7cdd64b4bdf89e7fe762d0a049e1f70709bf3ef2e95bbc4cfc00"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"e4ef000d25ea6c0dcc101782bf5fcd2af2a911e6aa7f8f770653c6d57206ae4b","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"98c042d59747ee82332e81dfb628c63bb8d4cfde504664f1e130bdd809b31254","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"SjwuM9m3J5z3mOAUfEyNRibjEiUgWzr_sHiOcl69KTqfZRpJKLP5cv9oFeJ8LeEAhzjR7_CQh9FzWD2w3FBVDg"},"schema":"pubphys.envelope/1"},"record_hash":"e4ef000d25ea6c0dcc101782bf5fcd2af2a911e6aa7f8f770653c6d57206ae4b","leaf_index":1778}