# 📐 L2 Spec — Computed Tomography (CT) — fan/cone-beam X-ray reconstruction Mismatch-Only Spec
**ID:** `L2-029-001` · **Status:** ⊙ Testnet (genesis catalog)
**Parents:** ⬆ Principle [`L1-029`](/artifact/l1/L1-029)
> **🎯 Tolerance (ε):** expression
> **⚖ Difficulty score:** 0.5 · **Delta tier:** 5
> **⛓ On-chain block:** 41552308
---
## 1. Domain Ω
**Type:** `range`
| Parameter | Unit | Range |
|---|---|---|
| H | px | 256 – 2048 |
| W | px | 256 – 2048 |
| Z | — | 32 – 4096 |
| Kvp | — | 60 – 140 |
| Mas | — | 1 – 1000 |
| Scatter | — | 0.0 – 0.3 |
| Pixel mm | mm | 0.1 – 5.0 |
| Truncation | — | 0.0 – 0.2 |
| N projections | — | 60 – 2880 |
| Beam hardening | — | 0.0 – 0.3 |
| Metal artifact | — | 0.0 – 0.5 |
| Patient motion | — | 0.0 – 0.3 |
## 2. Tolerance (ε)
**Type:** `fn`
```
24.0 + 2.0 * log10(mAs / 10) - 10.0 * beam_hardening - 8.0 * scatter - 5.0 * patient_motion
```
## 3. Difficulty
| Property | Value |
|---|---|
| Difficulty score | 0.5 |
| Delta tier | 5 |
## 4. Fingerprint
`8d3e069284612147a44b702f22598992880f419e999c0d9117d7c61689fe0e84`
## 5. On-chain Registration
- **Chain hash:** `0x3fbe8630819ad5a439088893d00a9fc8ed9598477cf96a7b4ab2b76b0b9ef84e`
- **Chain tx hash:** `0x8d80638760baad8a099acefe6538449e265735deacd2a246c8c0ce7a8344cd8a`
- **Chain block:** `41552308`
---
## File Mapping
This bundle consists of: `L2-029-001.md`, `L2-029-001.json`.
| File | Role | How to regenerate |
|------|------|-------------------|
| `L2-029-001.md` | Source of truth — edit this | Human or LLM |
| `L2-029-001.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 `L2-029-001`._
_Edit it, regenerate the JSON, and submit at [/submit](/submit) to claim the artifact._