{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"184e7ea19a90b3b48bddbbeb3005815f7494c07e1923760eebd652264c9403f5","created":"2026-10-15T23:43:22Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["6b685a71d394ce7d9d2643fbf7d1920ba56f4c584eb8b55669d69377a2e88983","ce59fb6cd812fc05906d0c60a71c75ea22bc686bcf38e7c3ef7010834d98ee7b"],"salt":"28c9befbf502545db05fa47108e87994e6c44ad3b33fbc562ccb7246c27d4ded","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"value","assisted_by":[],"external_id":"astro.neutron-star-interiors.cw-mountains","kind":"well-posed","literature_status":"open","n":"2","parents":[],"plain":"A spinning neutron star with a tiny bump on its crust would emit a steady gravitational-wave hum. None has been detected, and it is not known how large a bump the crust can support or how large real bumps are.","posed_since":"","precise":"Searches for continuous gravitational waves from known pulsars set upper limits on ellipticity $\\epsilon$ of order $10^{-8}\\ \\text{to}\\ 10^{-9}$ for some nearby millisecond pulsars. Determine the maximum ellipticity a realistic crust can sustain (estimates range from about $10^{-9}\\ \\text{to}\\ 10^{-6}$ depending on how the mountain is built) and whether a floor near $\\epsilon \\sim 10^{-9}$ exists, as suggested by millisecond-pulsar spin-down.","problem_ref":"6b685a71d394ce7d9d2643fbf7d1920ba56f4c584eb8b55669d69377a2e88983","references":"","settled_by":"A detection of continuous gravitational waves, or a crust-elasticity calculation with a self-consistent formation history giving $\\epsilon_{\\max}$ below current limits.","status_note":"Searches of LIGO-Virgo-KAGRA fourth observing run data were in progress in 2026 with no reported detection.","title":"How large are neutron-star mountains, given no continuous gravitational waves?","topic_ref":null},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"4bb1afe535b98c88a088f1b12a2a378fa2c651f4dc51c0656a4b4bcb6d46feca","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"a680bcce6363dc1f2cf537352d12a70dd9d0a59cd24e994bb39a011c82744b32","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"DGZ6BkqPe04OdHxv4tCei2AUsZW35h1ZtCaURU4oJ1tHhjV2cuyYOVHvtLKQEqwr3M2EKHuQoQyJLZQqIlZeBw"},"schema":"pubphys.envelope/1"},"record_hash":"4bb1afe535b98c88a088f1b12a2a378fa2c651f4dc51c0656a4b4bcb6d46feca","leaf_index":2390}