# 📐 L2 Spec — Contrast-Enhanced Ultrasound (CEUS) Mismatch-Only Spec
**ID:** `L2-062-001` · **Status:** ⊙ Testnet (genesis catalog)
**Parents:** ⬆ Principle [`L1-062`](/artifact/l1/L1-062)
> **🎯 Tolerance (ε):** expression
> **⚖ Difficulty score:** 0.5 · **Delta tier:** 5
> **⛓ On-chain block:** 41553362
---
## 1. Domain Ω
**Type:** `range`
| Parameter | Unit | Range |
|---|---|---|
| Mi | — | 0.05 – 0.5 |
| F mhz | MHz | 1 – 15 |
| Snr db | dB | 0.0 – 35.0 |
| N frames | — | 30 – 1000 |
| N elements | — | 32 – 256 |
| Flow artifacts | — | 0.0 – 0.3 |
| Contrast washout | — | 0.0 – 0.5 |
| Bubble destruction | — | 0.0 – 0.3 |
| Nonlinear tissue harmonics | — | 0.0 – 0.3 |
## 2. Tolerance (ε)
**Type:** `fn`
```
14.0 + 0.3 * SNR_dB - 8.0 * bubble_destruction - 6.0 * nonlinear_tissue_harmonics
```
## 3. Difficulty
| Property | Value |
|---|---|
| Difficulty score | 0.5 |
| Delta tier | 5 |
## 4. Fingerprint
`45bd8d623f32257169d4f05c0ffe23af72b247087005c17b092446d48c2a6e60`
## 5. On-chain Registration
- **Chain hash:** `0x24007239a5d0c20afa42033ecafe50298c0869ceda3df4214326d7758b058dc4`
- **Chain tx hash:** `0x203595627759af733f8054388e129dce93b8b36783808f6a249d535d9d3bd429`
- **Chain block:** `41553362`
---
## File Mapping
This bundle consists of: `L2-062-001.md`, `L2-062-001.json`.
| File | Role | How to regenerate |
|------|------|-------------------|
| `L2-062-001.md` | Source of truth — edit this | Human or LLM |
| `L2-062-001.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 `L2-062-001`._
_Edit it, regenerate the JSON, and submit at [/submit](/submit) to claim the artifact._