Pith Number

pith:HFV7IGDL

pith:1997:HFV7IGDL5DERCDF2V4SVVZHIYU

not attested not anchored not stored refs pending

The FIRST Radio-Loud Broad Absorption Line QSO and Evidence for a Hidden Population of Quasars

David J. Helfand (Columbia), Isobel M. Hook (ESO), Michael D. Gregg (IGPP/LLNL), Richard G. McMahon (Cambridge), Richard L. White (STScI), Robert H. Becker (UC Davis)

arxiv:astro-ph/9702012 v1 · 1997-01-31 · 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{HFV7IGDL5DERCDF2V4SVVZHIYU}

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	2026-05-18T02:40:35.228574Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

396bf4186be8c9110cbaaf255ae4e8c51f2da5181b6b6866286001141f6d1a04

Aliases

arxiv: astro-ph/9702012 · arxiv_version: astro-ph/9702012v1 · doi: 10.48550/arxiv.astro-ph/9702012 · pith_short_12: HFV7IGDL5DER · pith_short_16: HFV7IGDL5DERCDF2 · pith_short_8: HFV7IGDL

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/HFV7IGDL5DERCDF2V4SVVZHIYU \
  | 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: 396bf4186be8c9110cbaaf255ae4e8c51f2da5181b6b6866286001141f6d1a04

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "3ad851f6b71fe1b4ac68dba200bff2bfba64a30a7c397f405d6163bbf2e1459a",
    "cross_cats_sorted": [],
    "license": "",
    "primary_cat": "astro-ph",
    "submitted_at": "1997-01-31T18:40:45Z",
    "title_canon_sha256": "f9c3944ecf1816a268aca089af9922baae458f1924061721f5cb3db0726b80b8"
  },
  "schema_version": "1.0",
  "source": {
    "id": "astro-ph/9702012",
    "kind": "arxiv",
    "version": 1
  }
}