honest per-material rebuild: N(E_F)xA_d(delta) verified + published pipeline + CC-BY-NC

PROVENANCE.md

@@ -1,37 +1,53 @@
-# Data Provenance and Attribution
-
-The OSC candidate list is a **derived, enriched dataset**. The underlying material
-records come from the **Computational 2D Materials Database (C2DB)** and are
-redistributed here under **CC-BY 4.0** with attribution. We do not claim ownership of
-the source records.
-
-## Source
-- **C2DB - Computational 2D Materials Database**, CAMD / Technical University of Denmark.
-  Web: https://c2db.fysik.dtu.dk , https://2dhub.org
-- Primary references:
-  - S. Haastrup et al., *The Computational 2D Materials Database: high-throughput
-    modeling and discovery of atomically thin crystals*, 2D Mater. 5, 042002 (2018).
-  - M. N. Gjerding et al., *Recent progress of the Computational 2D Materials Database
-    (C2DB)*, 2D Mater. 8, 044002 (2021).
-- Twistability / superconductivity context (candidate motivation):
-  - Jiang et al., Science (2026), doi:10.1126/science.adu1550.
-  - Petralanda et al., Science (2026), doi:10.1126/science.adu2107.
-
-## What we changed (our contribution)
-Starting from C2DB fields (formula, magnetic state, band gap PBE, energy above hull,
-layer group, C2DB UID), we added and edited:
-- `osc_id` - a stable OSC identifier.
-- `family` - materials-family tag (TMD / MNX / TM-oxide / ...), computed from composition.
-- `is_metal` - metallic flag from the band gap.
-- `weight_class` + `score_mult` - a structure-only compute-cost class (light/medium/heavy)
-  we define for participant hardware matching.
-- `sc_relevance` - **our triage prior** (0-1) for which materials to try first. This is a
-  screening heuristic, **not** a prediction or a C2DB quantity.
-- Light editing: removed unparseable rows, normalized formulas, sorted by relevance.
-
-The `sc_relevance`, `weight_class`, `family`, and `osc_id` fields are OSC-original and are
-released under Apache-2.0 as part of this challenge. The source physical quantities remain
-attributable to C2DB under CC-BY 4.0.
-
-## How the source was accessed
-Public C2DB web interface (dynamically-stable subset). No private or gated data was used.
+# Provenance & License
+
+## Source data — C2DB
+
+The crystal structures and the base electronic-structure properties in OSC are derived from the
+**Computational 2D Materials Database (C2DB)**, Technical University of Denmark.
+
+- **License: Creative Commons Attribution-NonCommercial 4.0 International (CC-BY-NC 4.0).**
+  https://creativecommons.org/licenses/by-nc/4.0/
+- C2DB material pages: https://c2db.fysik.dtu.dk/
+
+Please cite C2DB when using OSC:
+> S. Haastrup et al., *The Computational 2D Materials Database: high-throughput modeling and
+> discovery of atomically thin crystals*, 2D Materials 5, 042002 (2018); and
+> M. N. Gjerding et al., 2D Materials 8, 044002 (2021).
+
+## What OSC adds (and how)
+
+From each C2DB structure, OSC computes — with the open scripts in `instrument/` and the
+organizer pipeline published in `pipeline/` — a single-band effective Hubbard model:
+
+- **N(E_F)**: Gaussian-broadened density of states at the Fermi level from a QE calculation
+  (states/eV/atom). Grid: the SCF k-mesh (coarse) for the active set, refined on a dense NSCF
+  grid for finalists.
+- **filling (δ)**: occupation of the band crossing E_F, weighted over the k-mesh, giving the
+  doping the many-body solver is run at.
+- **t**: nearest-neighbour hopping from the single active-band width (t = W_band / z).
+- **U/t = 8**: a documented correlated-regime convention (control parameter, cRPA pending).
+
+These derived quantities are **also released under CC-BY-NC 4.0**, consistent with the source.
+
+## Non-commercial scope of the challenge
+
+Because the source data is CC-BY-NC 4.0, **OSC is a non-commercial, academic open-science
+challenge**:
+
+- The data and derived models may be used for research and education, **not for commercial
+  purposes**, with attribution to C2DB.
+- Prizes are **research awards** (recognition + co-authorship + a token honorarium), not a sale
+  or commercial licensing of the data.
+- Participants retain the rights to their own methods and code; winners share reproducible code
+  under an open contributor license.
+
+If you intend any commercial use of the underlying materials data, obtain permission from C2DB
+directly — OSC does not and cannot grant commercial rights to C2DB-derived data.
+
+## Verification engine
+
+The precise strongly-correlated solver used to set the *verified* scores is operated by the
+organizers and is not redistributed. Its **inputs** (per-material t, U, N(E_F), filling) and its
+**outputs** (the d-wave amplitude A_d(δ) per filling) are fully published here, so every verified
+score is reproducible in its construction; only the internal solver implementation is withheld
+to keep the ranking hard to game.