{"record_type":"pith_number_record","schema_url":"https://pith.science/schemas/pith-number/v1.json","pith_number":"pith:2015:E2QRQR5LWYK5VSOBLMACF4I3AA","short_pith_number":"pith:E2QRQR5L","schema_version":"1.0","canonical_sha256":"26a11847abb615dac9c15b0022f11b000ea63a62be08abf157d7731040709dfa","source":{"kind":"arxiv","id":"1505.04575","version":1},"attestation_state":"computed","paper":{"title":"Small-scale dynamos on the solar surface: dependence on magnetic Prandtl number","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.SR","authors_text":"H.C. Spruit, I. Thaler","submitted_at":"2015-05-18T10:00:51Z","abstract_excerpt":"The question of possible small-scale dynamo action in the surface layers of the Sun is revisited with realistic 3D MHD simulations. As in other MHD problems, dynamo action is found to be a sensitive function of the magnetic Prandtl number ${\\rm P_{\\rm m} }=\\nu/\\eta$; it disappears below a critical value ${\\rm P_{\\rm c}}$ which is a function of the numerical resolution. At a grid spacing of 3.5 km, ${\\rm P_{\\rm c}}$ based on the hyperdiffusivities implemented in the code (STAGGER) is $\\approx 1$, increasing with increasing grid spacing. As in other settings, it remains uncertain whether small s"},"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":"1505.04575","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.SR","submitted_at":"2015-05-18T10:00:51Z","cross_cats_sorted":[],"title_canon_sha256":"a5f276ebf7207515cfa57676d05cad04187ebb8b3caa3216fbd4c4f55fd011d4","abstract_canon_sha256":"7c7ba79f147636f28753c16b8dcaa4209e7ee2a1266c1ad39b9e12029dc18f48"},"schema_version":"1.0"},"receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T01:55:00.373418Z","signature_b64":"a1fLVvS8WHWzyJr3A/+TbZyrevVlSAc7YM6y+FGq3TbEjZ6ecOCdWNOXnlYWdEw3Ej59+t5yBYA5MWDIkEOADQ==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"26a11847abb615dac9c15b0022f11b000ea63a62be08abf157d7731040709dfa","last_reissued_at":"2026-05-18T01:55:00.372635Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T01:55:00.372635Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"graph_snapshot":{"paper":{"title":"Small-scale dynamos on the solar surface: dependence on magnetic Prandtl number","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.SR","authors_text":"H.C. Spruit, I. Thaler","submitted_at":"2015-05-18T10:00:51Z","abstract_excerpt":"The question of possible small-scale dynamo action in the surface layers of the Sun is revisited with realistic 3D MHD simulations. As in other MHD problems, dynamo action is found to be a sensitive function of the magnetic Prandtl number ${\\rm P_{\\rm m} }=\\nu/\\eta$; it disappears below a critical value ${\\rm P_{\\rm c}}$ which is a function of the numerical resolution. At a grid spacing of 3.5 km, ${\\rm P_{\\rm c}}$ based on the hyperdiffusivities implemented in the code (STAGGER) is $\\approx 1$, increasing with increasing grid spacing. As in other settings, it remains uncertain whether small s"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1505.04575","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":""},"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":"1505.04575","created_at":"2026-05-18T01:55:00.372755+00:00"},{"alias_kind":"arxiv_version","alias_value":"1505.04575v1","created_at":"2026-05-18T01:55:00.372755+00:00"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1505.04575","created_at":"2026-05-18T01:55:00.372755+00:00"},{"alias_kind":"pith_short_12","alias_value":"E2QRQR5LWYK5","created_at":"2026-05-18T12:29:17.054201+00:00"},{"alias_kind":"pith_short_16","alias_value":"E2QRQR5LWYK5VSOB","created_at":"2026-05-18T12:29:17.054201+00:00"},{"alias_kind":"pith_short_8","alias_value":"E2QRQR5L","created_at":"2026-05-18T12:29:17.054201+00:00"}],"events":[],"event_summary":{},"paper_claims":[],"inbound_citations":{"count":0,"internal_anchor_count":0,"sample":[]},"formal_canon":{"evidence_count":0,"sample":[],"anchors":[]},"links":{"html":"https://pith.science/pith/E2QRQR5LWYK5VSOBLMACF4I3AA","json":"https://pith.science/pith/E2QRQR5LWYK5VSOBLMACF4I3AA.json","graph_json":"https://pith.science/api/pith-number/E2QRQR5LWYK5VSOBLMACF4I3AA/graph.json","events_json":"https://pith.science/api/pith-number/E2QRQR5LWYK5VSOBLMACF4I3AA/events.json","paper":"https://pith.science/paper/E2QRQR5L"},"agent_actions":{"view_html":"https://pith.science/pith/E2QRQR5LWYK5VSOBLMACF4I3AA","download_json":"https://pith.science/pith/E2QRQR5LWYK5VSOBLMACF4I3AA.json","view_paper":"https://pith.science/paper/E2QRQR5L","resolve_alias":"https://pith.science/api/pith-number/resolve?arxiv=1505.04575&json=true","fetch_graph":"https://pith.science/api/pith-number/E2QRQR5LWYK5VSOBLMACF4I3AA/graph.json","fetch_events":"https://pith.science/api/pith-number/E2QRQR5LWYK5VSOBLMACF4I3AA/events.json","actions":{"anchor_timestamp":"https://pith.science/pith/E2QRQR5LWYK5VSOBLMACF4I3AA/action/timestamp_anchor","attest_storage":"https://pith.science/pith/E2QRQR5LWYK5VSOBLMACF4I3AA/action/storage_attestation","attest_author":"https://pith.science/pith/E2QRQR5LWYK5VSOBLMACF4I3AA/action/author_attestation","sign_citation":"https://pith.science/pith/E2QRQR5LWYK5VSOBLMACF4I3AA/action/citation_signature","submit_replication":"https://pith.science/pith/E2QRQR5LWYK5VSOBLMACF4I3AA/action/replication_record"}},"created_at":"2026-05-18T01:55:00.372755+00:00","updated_at":"2026-05-18T01:55:00.372755+00:00"}