{"record_type":"pith_number_record","schema_url":"https://pith.science/schemas/pith-number/v1.json","pith_number":"pith:2026:62JZO6I2ATH7OKH2NJ3PUQ3YMH","short_pith_number":"pith:62JZO6I2","schema_version":"1.0","canonical_sha256":"f69397791a04cff728fa6a76fa437861f4a419f754ba9750139a9250d0e7d09b","source":{"kind":"arxiv","id":"2602.00285","version":3},"attestation_state":"computed","paper":{"title":"Defects, Corrugation and Temperature Govern Rarefied-Air Drag on Graphene Coatings","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"Coating alumina with graphene reduces the tangential momentum accommodation coefficient of nitrogen, lowering drag in rarefied air.","cross_cats":["physics.chem-ph","physics.flu-dyn"],"primary_cat":"cond-mat.mtrl-sci","authors_text":"Antimo Marrazzo, Davide Bidoggia, Maria Peressi, Samuel Cajahuaringa","submitted_at":"2026-01-30T20:14:33Z","abstract_excerpt":"In rarefied atmospheric environments, where continuum fluid dynamics breaks down, aerodynamic drag is governed by gas-surface momentum exchange, making surface structure and chemistry key design knobs. Using molecular dynamics simulations, we show that coating the $\\alpha$-Al2O3(0001) surface with graphene markedly reduces the tangential momentum accommodation coefficient (TMAC) of N2, shifting scattering toward more specular reflection and thereby lowering drag; we further benchmark this response against graphite. The reduction strengthens up to 900 K. While structural defects can increase TM"},"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":true},"canonical_record":{"source":{"id":"2602.00285","kind":"arxiv","version":3},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.mtrl-sci","submitted_at":"2026-01-30T20:14:33Z","cross_cats_sorted":["physics.chem-ph","physics.flu-dyn"],"title_canon_sha256":"662da5a8e89bc47f69ae9c23a54264e94712a89956c69788666e0c53bdc0d4cc","abstract_canon_sha256":"a5883d97488dea8b6fbd82855cc8c0b43e12c967c40d4b15d6a0273c3b2aed0a"},"schema_version":"1.0"},"receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-06-02T01:03:41.617865Z","signature_b64":"FYJZXgpKX0CN6zuJ/PWoUSmDsFOGZ5xJ+o8yJUGC1ZHHNimseTCdm3LsqXpm1ZkmHhpVdK6V00p8UTDKXlUKAQ==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"f69397791a04cff728fa6a76fa437861f4a419f754ba9750139a9250d0e7d09b","last_reissued_at":"2026-06-02T01:03:41.617381Z","signature_status":"signed_v1","first_computed_at":"2026-06-02T01:03:41.617381Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"graph_snapshot":{"paper":{"title":"Defects, Corrugation and Temperature Govern Rarefied-Air Drag on Graphene Coatings","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"Coating alumina with graphene reduces the tangential momentum accommodation coefficient of nitrogen, lowering drag in rarefied air.","cross_cats":["physics.chem-ph","physics.flu-dyn"],"primary_cat":"cond-mat.mtrl-sci","authors_text":"Antimo Marrazzo, Davide Bidoggia, Maria Peressi, Samuel Cajahuaringa","submitted_at":"2026-01-30T20:14:33Z","abstract_excerpt":"In rarefied atmospheric environments, where continuum fluid dynamics breaks down, aerodynamic drag is governed by gas-surface momentum exchange, making surface structure and chemistry key design knobs. Using molecular dynamics simulations, we show that coating the $\\alpha$-Al2O3(0001) surface with graphene markedly reduces the tangential momentum accommodation coefficient (TMAC) of N2, shifting scattering toward more specular reflection and thereby lowering drag; we further benchmark this response against graphite. The reduction strengthens up to 900 K. While structural defects can increase TM"},"claims":{"count":4,"items":[{"kind":"strongest_claim","text":"coating the α-Al2O3(0001) surface with graphene markedly reduces the tangential momentum accommodation coefficient (TMAC) of N2, shifting scattering toward more specular reflection and thereby lowering drag; the reduction strengthens up to 900 K. While structural defects can increase TMAC via defect-induced corrugation and local atomic and electronic rearrangements, graphene retains its performance at experimentally relevant defect densities.","source":"verdict.strongest_claim","status":"machine_extracted","claim_id":"C1","attestation":"unclaimed"},{"kind":"weakest_assumption","text":"The molecular dynamics simulations provide an accurate representation of the real-world gas-surface momentum exchange for N2 on graphene-coated alumina, including the effects of temperature and defects.","source":"verdict.weakest_assumption","status":"machine_extracted","claim_id":"C2","attestation":"unclaimed"},{"kind":"one_line_summary","text":"Graphene coating on alumina reduces TMAC of N2 in rarefied conditions, lowering drag, with the effect strengthening to 900 K and remaining robust to defects.","source":"verdict.one_line_summary","status":"machine_extracted","claim_id":"C3","attestation":"unclaimed"},{"kind":"headline","text":"Coating alumina with graphene reduces the tangential momentum accommodation coefficient of nitrogen, lowering drag in rarefied air.","source":"verdict.pith_extraction.headline","status":"machine_extracted","claim_id":"C4","attestation":"unclaimed"}],"snapshot_sha256":"ca6f436407fbf8a4be8a8fad7b977f9105cf12933e62bd313f656ef58c030ce4"},"source":{"id":"2602.00285","kind":"arxiv","version":3},"verdict":{"id":"4a78897a-e7c6-4b11-a3f6-b405aa15d310","model_set":{"reader":"grok-4.3"},"created_at":"2026-05-16T09:04:20.291111Z","strongest_claim":"coating the α-Al2O3(0001) surface with graphene markedly reduces the tangential momentum accommodation coefficient (TMAC) of N2, shifting scattering toward more specular reflection and thereby lowering drag; the reduction strengthens up to 900 K. While structural defects can increase TMAC via defect-induced corrugation and local atomic and electronic rearrangements, graphene retains its performance at experimentally relevant defect densities.","one_line_summary":"Graphene coating on alumina reduces TMAC of N2 in rarefied conditions, lowering drag, with the effect strengthening to 900 K and remaining robust to defects.","pipeline_version":"pith-pipeline@v0.9.0","weakest_assumption":"The molecular dynamics simulations provide an accurate representation of the real-world gas-surface momentum exchange for N2 on graphene-coated alumina, including the effects of temperature and defects.","pith_extraction_headline":"Coating alumina with graphene reduces the tangential momentum accommodation coefficient of nitrogen, lowering drag in rarefied air."},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2602.00285/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":2,"snapshot_sha256":"4921788eacd5e1d3787dff13e6e853972fc82527b9507946eaf8d0669b6a01f7"},"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":"2602.00285","created_at":"2026-06-02T01:03:41.617439+00:00"},{"alias_kind":"arxiv_version","alias_value":"2602.00285v3","created_at":"2026-06-02T01:03:41.617439+00:00"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2602.00285","created_at":"2026-06-02T01:03:41.617439+00:00"},{"alias_kind":"pith_short_12","alias_value":"62JZO6I2ATH7","created_at":"2026-06-02T01:03:41.617439+00:00"},{"alias_kind":"pith_short_16","alias_value":"62JZO6I2ATH7OKH2","created_at":"2026-06-02T01:03:41.617439+00:00"},{"alias_kind":"pith_short_8","alias_value":"62JZO6I2","created_at":"2026-06-02T01:03:41.617439+00:00"}],"events":[],"event_summary":{},"paper_claims":[],"inbound_citations":{"count":0,"internal_anchor_count":0,"sample":[]},"formal_canon":{"evidence_count":2,"sample":[],"anchors":[]},"links":{"html":"https://pith.science/pith/62JZO6I2ATH7OKH2NJ3PUQ3YMH","json":"https://pith.science/pith/62JZO6I2ATH7OKH2NJ3PUQ3YMH.json","graph_json":"https://pith.science/api/pith-number/62JZO6I2ATH7OKH2NJ3PUQ3YMH/graph.json","events_json":"https://pith.science/api/pith-number/62JZO6I2ATH7OKH2NJ3PUQ3YMH/events.json","paper":"https://pith.science/paper/62JZO6I2"},"agent_actions":{"view_html":"https://pith.science/pith/62JZO6I2ATH7OKH2NJ3PUQ3YMH","download_json":"https://pith.science/pith/62JZO6I2ATH7OKH2NJ3PUQ3YMH.json","view_paper":"https://pith.science/paper/62JZO6I2","resolve_alias":"https://pith.science/api/pith-number/resolve?arxiv=2602.00285&json=true","fetch_graph":"https://pith.science/api/pith-number/62JZO6I2ATH7OKH2NJ3PUQ3YMH/graph.json","fetch_events":"https://pith.science/api/pith-number/62JZO6I2ATH7OKH2NJ3PUQ3YMH/events.json","actions":{"anchor_timestamp":"https://pith.science/pith/62JZO6I2ATH7OKH2NJ3PUQ3YMH/action/timestamp_anchor","attest_storage":"https://pith.science/pith/62JZO6I2ATH7OKH2NJ3PUQ3YMH/action/storage_attestation","attest_author":"https://pith.science/pith/62JZO6I2ATH7OKH2NJ3PUQ3YMH/action/author_attestation","sign_citation":"https://pith.science/pith/62JZO6I2ATH7OKH2NJ3PUQ3YMH/action/citation_signature","submit_replication":"https://pith.science/pith/62JZO6I2ATH7OKH2NJ3PUQ3YMH/action/replication_record"}},"created_at":"2026-06-02T01:03:41.617439+00:00","updated_at":"2026-06-02T01:03:41.617439+00:00"}