Pith Number

pith:HHKS2QK2

pith:2008:HHKS2QK2OJ27YWXQ2KKTHHSNRL

not attested not anchored not stored refs pending

A Deep XMM-Newton Observation of the Quasar 3C 287

(2) Harvard-Smithsonian CfA), A. Siemiginowska (2) ((1) University of Michigan, E. Cackett (1), G. Salvesen (1), J. M. Miller (1)

arxiv:0809.4691 v1 · 2008-09-26 · astro-ph

Open paper page JSON Open Graph Bundle Merged state Verified badge What is a Pith Number?

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{HHKS2QK2OJ27YWXQ2KKTHHSNRL}

Prints a linked badge after your title and injects PDF metadata. Compiles on arXiv. Learn more · Embed verified badge

Record completeness

1 Bitcoin timestamp

2 Internet Archive

3 Author claim open · sign in to claim

4 Citations open

5 Replications open

✓ Portable graph bundle live · download bundle · merged state

The bundle contains the canonical record plus signed events. A mirror can host it anywhere and recompute the same current state with the deterministic merge algorithm.

Receipt and verification

First computed	2026-05-18T04:29:26.416971Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

39d52d415a7275fc5af0d295339e4d8af1cfc1186bdbbfd686d12c44de92629c

Aliases

arxiv: 0809.4691 · arxiv_version: 0809.4691v1 · doi: 10.48550/arxiv.0809.4691 · pith_short_12: HHKS2QK2OJ27 · pith_short_16: HHKS2QK2OJ27YWXQ · pith_short_8: HHKS2QK2

Agent API

Resolver JSON Graph JSON Events JSON Schema Signing key

Verify this Pith Number yourself

curl -sH 'Accept: application/ld+json' https://pith.science/pith/HHKS2QK2OJ27YWXQ2KKTHHSNRL \
  | jq -c '.canonical_record' \
  | python3 -c "import sys,json,hashlib; b=json.dumps(json.loads(sys.stdin.read()), sort_keys=True, separators=(',',':'), ensure_ascii=False).encode(); print(hashlib.sha256(b).hexdigest())"
# expect: 39d52d415a7275fc5af0d295339e4d8af1cfc1186bdbbfd686d12c44de92629c

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "c43988e1d71fc7676490505a7ae245b489f7e14195ca47a020b13e49329e2c02",
    "cross_cats_sorted": [],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "astro-ph",
    "submitted_at": "2008-09-26T19:01:31Z",
    "title_canon_sha256": "0185ca8afa6ac4d48c2de39ab9a21fb74c254e2fed141a4e205a025cc2e974ef"
  },
  "schema_version": "1.0",
  "source": {
    "id": "0809.4691",
    "kind": "arxiv",
    "version": 1
  }
}