Pith Number

pith:SOTXRVK4

pith:2026:SOTXRVK4VWFKK5KWA2M3WRNMMI

not attested not anchored not stored refs resolved

The compact neutron star in 4U 1746-37 revisited: Reassessing the mass and radius

Chang-Hwan Lee, Kwang Hyun Sung, Kyujin Kwak, Myungkuk Kim, Young-Min Kim

Significant X-ray flux blocking allows the neutron star in 4U 1746-37 to match standard mass and radius values.

arxiv:2605.14264 v1 · 2026-05-14 · astro-ph.HE · astro-ph.SR

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\usepackage{pith}
\pithnumber{SOTXRVK4VWFKK5KWA2M3WRNMMI}

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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.

Claims

C1strongest claim

Significant blocking factors (B ≳ 0.8, reducing the observed flux to ∼17% of the intrinsic emission) permit neutron star parameters consistent with the canonical values: M = 1.59 ± 0.69 M⊙, R = 13.0 ± 5.45 km, or M = 2.12 ± 1.08 M⊙, R = 9.80 ± 4.13 km.

C2weakest assumption

The assumption that significant flux blocking (B ≳ 0.8) occurs and varies with photospheric radius, thereby explaining the anomalously large peak-to-touchdown flux ratio of ∼2.0.

C3one line summary

Significant X-ray flux blocking in 4U 1746-37 allows the neutron star to have canonical mass and radius values of 1.59 solar masses and 13 km or 2.12 solar masses and 9.8 km.

References

114 extracted · 114 resolved · 32 Pith anchors

[1] Antoniadis, J. et al. 2013, Science, 340, 6131 2013

[2] & Zwicky , F 1934

[3] 2009, , 138, 50 2009

[4] J., & Smale , A 2004

[5] 1971, , 170, 299 1971

Formal links

2 machine-checked theorem links

Receipt and verification

First computed	2026-05-17T23:39:10.455548Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

93a778d55cad8aa575560699bb45ac6212704d59a63239b6601853ca35059e5c

Aliases

arxiv: 2605.14264 · arxiv_version: 2605.14264v1 · doi: 10.48550/arxiv.2605.14264 · pith_short_12: SOTXRVK4VWFK · pith_short_16: SOTXRVK4VWFKK5KW · pith_short_8: SOTXRVK4

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/SOTXRVK4VWFKK5KWA2M3WRNMMI \
  | 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: 93a778d55cad8aa575560699bb45ac6212704d59a63239b6601853ca35059e5c

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "22ad526f2cadd70187bf71d4f8ad08f969fd2083350b7070b8ce725f19bcbc55",
    "cross_cats_sorted": [
      "astro-ph.SR"
    ],
    "license": "http://creativecommons.org/licenses/by-nc-nd/4.0/",
    "primary_cat": "astro-ph.HE",
    "submitted_at": "2026-05-14T02:08:14Z",
    "title_canon_sha256": "7bcb9d11c5184035b271d8d0574acd1fde12bbf90a538865868b955ae20f394a"
  },
  "schema_version": "1.0",
  "source": {
    "id": "2605.14264",
    "kind": "arxiv",
    "version": 1
  }
}