Pith Number

pith:55YOKZLB

pith:2004:55YOKZLBRHQ2YUZDG7XXCHJHJK

not attested not anchored not stored refs pending

XMM-Newton EPIC observations of 21 low-redshift PG quasars

D. Porquet (MPE), J.N. Reeves (LHEA, NASA Goddard), P. O'Brien (Leicester), W. Brinkmann (MPE)

arxiv:astro-ph/0404385 v1 · 2004-04-20 · 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{55YOKZLBRHQ2YUZDG7XXCHJHJK}

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	2026-05-18T01:07:32.574159Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

ef70e5656189e1ac532337ef711d274a84ca3c2a585dd60c50541127d37ac372

Aliases

arxiv: astro-ph/0404385 · arxiv_version: astro-ph/0404385v1 · doi: 10.48550/arxiv.astro-ph/0404385 · pith_short_12: 55YOKZLBRHQ2 · pith_short_16: 55YOKZLBRHQ2YUZD · pith_short_8: 55YOKZLB

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/55YOKZLBRHQ2YUZDG7XXCHJHJK \
  | 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: ef70e5656189e1ac532337ef711d274a84ca3c2a585dd60c50541127d37ac372

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "6b5baa902c70033f4b26079e99911b17a7c4402c882860d6469a23ced0fdd402",
    "cross_cats_sorted": [],
    "license": "",
    "primary_cat": "astro-ph",
    "submitted_at": "2004-04-20T13:59:12Z",
    "title_canon_sha256": "fabfd4c17e9b4597b7feb363c7de16b14a1bcd261cdad840c788779df387bd90"
  },
  "schema_version": "1.0",
  "source": {
    "id": "astro-ph/0404385",
    "kind": "arxiv",
    "version": 1
  }
}