Pith Number

pith:26Z5KMYL

pith:1998:26Z5KMYLGQ42YLBBH2AY3ZCW6E

not attested not anchored not stored refs pending

The X-ray Spectral Variability of the Seyfert Galaxy NGC 3227

A.Ptak, H.Netzer, I.M.George, K.Nandra, R.F.Mushotzky, T.J.Turner, T.Yaqoob

arxiv:astro-ph/9806392 v1 · 1998-06-30 · 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{26Z5KMYLGQ42YLBBH2AY3ZCW6E}

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	2026-05-18T01:07:37.274442Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

d7b3d5330b3439ac2c213e818de456f12660e8e93e84711b5ab7067239318fee

Aliases

arxiv: astro-ph/9806392 · arxiv_version: astro-ph/9806392v1 · doi: 10.48550/arxiv.astro-ph/9806392 · pith_short_12: 26Z5KMYLGQ42 · pith_short_16: 26Z5KMYLGQ42YLBB · pith_short_8: 26Z5KMYL

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/26Z5KMYLGQ42YLBBH2AY3ZCW6E \
  | 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: d7b3d5330b3439ac2c213e818de456f12660e8e93e84711b5ab7067239318fee

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "796f30a91ea609df4119e94200cb904e02f51afe9c5b14d25597367d6248f7c0",
    "cross_cats_sorted": [],
    "license": "",
    "primary_cat": "astro-ph",
    "submitted_at": "1998-06-30T16:09:52Z",
    "title_canon_sha256": "5dca4264c3c152e87b0bb52efbc98e263f5ea1267a6a1fda90b328b5fae64e63"
  },
  "schema_version": "1.0",
  "source": {
    "id": "astro-ph/9806392",
    "kind": "arxiv",
    "version": 1
  }
}