# 📐 L2 Spec — Neutron Powder Rietveld Spec
**ID:** `L2-135-001` · **Status:** ⊙ Testnet (genesis catalog)
**Parents:** ⬆ Principle [`L1-135`](/artifact/l1/L1-135)
> **🎯 Tolerance (ε):** expression
> **⚖ Difficulty score:** 0.35 · **Delta tier:** 5
> **⛓ On-chain block:** 41554218
---
## 1. Domain Ω
**Type:** `range`
| Parameter | Unit | Range |
|---|---|---|
| N atoms | — | 1 – 1000 |
| N points | — | 1000 – 100000 |
| Lambda a | — | 0.5 – 6.0 |
| Absorption correction | — | 0.0 – 0.3 |
| Magnetic interference | — | 0.0 – 0.5 |
| Preferred orientation | — | 0.0 – 0.5 |
| Background model error | — | 0.0 – 0.2 |
| Thermal diffuse scatter | — | 0.0 – 0.2 |
## 2. Tolerance (ε)
**Type:** `fn`
```
0.03 + 0.1 * preferred_orientation + 0.1 * absorption_correction + 0.1 * magnetic_interference + 0.05 * thermal_diffuse_scatter
```
## 3. Difficulty
| Property | Value |
|---|---|
| Difficulty score | 0.35 |
| Delta tier | 5 |
## 4. Fingerprint
`ddf887093587d0168290ce91eb56a42457a27bce66d56811ff171c780a6b2a55`
## 5. On-chain Registration
- **Chain hash:** `0xfae2a0889f233f4272a7b160de29f827071f9a887b31688d4e346bf8ebf872e5`
- **Chain tx hash:** `0x3eaa0ee97554c4419fcd0012d9bfd846837604f85300fc9f9420ba55c0f95a69`
- **Chain block:** `41554218`
---
## File Mapping
This bundle consists of: `L2-135-001.md`, `L2-135-001.json`.
| File | Role | How to regenerate |
|------|------|-------------------|
| `L2-135-001.md` | Source of truth — edit this | Human or LLM |
| `L2-135-001.json` | Structured metadata for the registry | LLM regenerates from the sections above |
**Prompt for your LLM after editing this Markdown:**
> Read the attached Markdown. Regenerate the sibling `.json` so every field matches.
> Preserve the schema documented in the rows above.
> Output each file in its own fenced code block tagged with the filename.
> Output only the JSON object.
_This Markdown was auto-synthesized from the catalog row for `L2-135-001`._
_Edit it, regenerate the JSON, and submit at [/submit](/submit) to claim the artifact._