{"record_type":"pith_number_record","schema_url":"https://pith.science/schemas/pith-number/v1.json","pith_number":"pith:2023:LLOPTUV4TYCG2H4PRWPYOSXC3A","short_pith_number":"pith:LLOPTUV4","schema_version":"1.0","canonical_sha256":"5adcf9d2bc9e046d1f8f8d9f874ae2d81669a661a2b41b71f189becc462c413d","source":{"kind":"arxiv","id":"2311.04989","version":1},"attestation_state":"computed","paper":{"title":"GR-Athena++: General-relativistic magnetohydrodynamics simulations of neutron star spacetimes","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.HE","astro-ph.IM"],"primary_cat":"gr-qc","authors_text":"Boris Daszuta, David Radice, Francesco Zappa, Jacob Fields, Peter Hammond, Sebastiano Bernuzzi, Simone Albanesi, William Cook","submitted_at":"2023-11-08T19:08:28Z","abstract_excerpt":"We present the extension of GR-Athena++ to general-relativistic magnetohydrodynamics (GRMHD) for applications to neutron star spacetimes. The new solver couples the constrained transport implementation of Athena++ to the Z4c formulation of the Einstein equations to simulate dynamical spacetimes with GRMHD using oct-tree adaptive mesh refinement. We consider benchmark problems for isolated and binary neutron star spacetimes demonstrating stable and convergent results at relatively low resolutions and without grid symmetries imposed. The code correctly captures magnetic field instabilities in no"},"verification_status":{"content_addressed":true,"pith_receipt":true,"author_attested":false,"weak_author_claims":0,"strong_author_claims":0,"externally_anchored":false,"storage_verified":false,"citation_signatures":0,"replication_records":0,"graph_snapshot":true,"references_resolved":false,"formal_links_present":false},"canonical_record":{"source":{"id":"2311.04989","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"gr-qc","submitted_at":"2023-11-08T19:08:28Z","cross_cats_sorted":["astro-ph.HE","astro-ph.IM"],"title_canon_sha256":"a5867be77f9caadfd18b93298baed1b744296f95bac80fee30812e2452345cd4","abstract_canon_sha256":"f341fafe5628873455cb4b7964e9dd8ef3e2f7e68793ad5ce81120a3bdee63fa"},"schema_version":"1.0"},"receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-05T07:10:53.191342Z","signature_b64":"4/2I8RmDfyklbZHw3EaBaq3SMZAtesRNX0MXqxR+j4yE1vmFx/hh1tQ+FTFwvJpim2YimUZaQVYeT+xnUJnMDw==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"5adcf9d2bc9e046d1f8f8d9f874ae2d81669a661a2b41b71f189becc462c413d","last_reissued_at":"2026-07-05T07:10:53.190857Z","signature_status":"signed_v1","first_computed_at":"2026-07-05T07:10:53.190857Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"graph_snapshot":{"paper":{"title":"GR-Athena++: General-relativistic magnetohydrodynamics simulations of neutron star spacetimes","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.HE","astro-ph.IM"],"primary_cat":"gr-qc","authors_text":"Boris Daszuta, David Radice, Francesco Zappa, Jacob Fields, Peter Hammond, Sebastiano Bernuzzi, Simone Albanesi, William Cook","submitted_at":"2023-11-08T19:08:28Z","abstract_excerpt":"We present the extension of GR-Athena++ to general-relativistic magnetohydrodynamics (GRMHD) for applications to neutron star spacetimes. The new solver couples the constrained transport implementation of Athena++ to the Z4c formulation of the Einstein equations to simulate dynamical spacetimes with GRMHD using oct-tree adaptive mesh refinement. We consider benchmark problems for isolated and binary neutron star spacetimes demonstrating stable and convergent results at relatively low resolutions and without grid symmetries imposed. The code correctly captures magnetic field instabilities in no"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2311.04989","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2311.04989/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"},"aliases":[{"alias_kind":"arxiv","alias_value":"2311.04989","created_at":"2026-07-05T07:10:53.190913+00:00"},{"alias_kind":"arxiv_version","alias_value":"2311.04989v1","created_at":"2026-07-05T07:10:53.190913+00:00"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2311.04989","created_at":"2026-07-05T07:10:53.190913+00:00"},{"alias_kind":"pith_short_12","alias_value":"LLOPTUV4TYCG","created_at":"2026-07-05T07:10:53.190913+00:00"},{"alias_kind":"pith_short_16","alias_value":"LLOPTUV4TYCG2H4P","created_at":"2026-07-05T07:10:53.190913+00:00"},{"alias_kind":"pith_short_8","alias_value":"LLOPTUV4","created_at":"2026-07-05T07:10:53.190913+00:00"}],"events":[],"event_summary":{},"paper_claims":[],"inbound_citations":{"count":3,"internal_anchor_count":0,"sample":[{"citing_arxiv_id":"2606.21659","citing_title":"Subgrid Modelling for Relativistic Magnetohydrodynamics with Machine Learning","ref_index":88,"is_internal_anchor":false},{"citing_arxiv_id":"2605.30430","citing_title":"Exact Mass Conservation in Binary Neutron Star Merger Simulations","ref_index":5,"is_internal_anchor":false},{"citing_arxiv_id":"2605.22921","citing_title":"Magnetic field dynamics in isolated neutron stars with an external dipole field","ref_index":62,"is_internal_anchor":false}]},"formal_canon":{"evidence_count":0,"sample":[],"anchors":[]},"links":{"html":"https://pith.science/pith/LLOPTUV4TYCG2H4PRWPYOSXC3A","json":"https://pith.science/pith/LLOPTUV4TYCG2H4PRWPYOSXC3A.json","graph_json":"https://pith.science/api/pith-number/LLOPTUV4TYCG2H4PRWPYOSXC3A/graph.json","events_json":"https://pith.science/api/pith-number/LLOPTUV4TYCG2H4PRWPYOSXC3A/events.json","paper":"https://pith.science/paper/LLOPTUV4"},"agent_actions":{"view_html":"https://pith.science/pith/LLOPTUV4TYCG2H4PRWPYOSXC3A","download_json":"https://pith.science/pith/LLOPTUV4TYCG2H4PRWPYOSXC3A.json","view_paper":"https://pith.science/paper/LLOPTUV4","resolve_alias":"https://pith.science/api/pith-number/resolve?arxiv=2311.04989&json=true","fetch_graph":"https://pith.science/api/pith-number/LLOPTUV4TYCG2H4PRWPYOSXC3A/graph.json","fetch_events":"https://pith.science/api/pith-number/LLOPTUV4TYCG2H4PRWPYOSXC3A/events.json","actions":{"anchor_timestamp":"https://pith.science/pith/LLOPTUV4TYCG2H4PRWPYOSXC3A/action/timestamp_anchor","attest_storage":"https://pith.science/pith/LLOPTUV4TYCG2H4PRWPYOSXC3A/action/storage_attestation","attest_author":"https://pith.science/pith/LLOPTUV4TYCG2H4PRWPYOSXC3A/action/author_attestation","sign_citation":"https://pith.science/pith/LLOPTUV4TYCG2H4PRWPYOSXC3A/action/citation_signature","submit_replication":"https://pith.science/pith/LLOPTUV4TYCG2H4PRWPYOSXC3A/action/replication_record"}},"created_at":"2026-07-05T07:10:53.190913+00:00","updated_at":"2026-07-05T07:10:53.190913+00:00"}