MATTOCCIA LABS / RESEARCH ENGINES / FUSION

Magnetic Plasma Dynamics — Quantitative Analysis of Public MAST Discharges

Study context

Problem addressed
Can the selected MAST discharge measurements be compared consistently across shots?
Contribution relative to existing methods
The experiment documents diagnostic selection, processing windows and reproducible signal summaries on public data.
Potential commercial use
Use the workflow as a starting point for comparing post-shot analysis procedures.

Market context and value assumptions on the engine page

FPE-001

Experiment conclusions

The ten signals from five MAST discharges yielded 757,500 valid samples. Plasma-current RMS levels were similar in the selected window, around 590–595 kA, while the probe’s spectral peaks varied between discharges.

Study limits. The comparison uses source-processed diagnostics. Peaks and transients are signal features. Physical identification requires further checks and calibration information.

Real experimental retrospective analysis. Version0.1.0; computational verification does not establish a new physical discovery.

Abstract and objective

Characterize comparable MAST diagnostic signals, their temporal/spectral properties and method sensitivity. Candidate events remain unclassified.

Dataset, selection and provenance

{
  "dataset": {
    "source": "UKAEA FAIR-MAST",
    "catalog_url": "https://s3.echo.stfc.ac.uk/mast/fairmast-meta/l2_shots.parquet",
    "catalog_sha256": "696f34fcfb8ef6e2bfa648f477b495e1c0ed40d460936af9d3057a4b1db21bf3",
    "license": "https://creativecommons.org/licenses/by-sa/4.0/",
    "data_level": 2,
    "type": "real_experimental_diagnostic_data_source_processed"
  },
  "configuration": {
    "shot_count": 5,
    "window_seconds": [
      0.05,
      0.35
    ]
  },
  "counts": {
    "catalog_shots": 11573,
    "selected_shots": 5,
    "selected_diagnostic_types": 2,
    "signals": 10,
    "samples": 757500,
    "valid_samples": 757500,
    "candidate_shots_examined": 5,
    "excluded_candidates": 0,
    "computed_signals": 10,
    "inconclusive_signals": 0
  }
}

Computational methods

Methods and all parameters are in the accompanying METHODOLOGY and manifest. Originals and transformed displays remain distinct. Units and unknown calibrations are explicit.

Verified quantitative findings

MCF-01 / DERIVED

Coverage and quality of comparable MAST diagnostics

Catalog selection fixed before values; explicit unit conversion and finite/regular-sampling checks

{
  "catalog_shots": 11573,
  "selected_shots": 5,
  "selected_diagnostic_types": 2,
  "signals": 10,
  "samples": 757500,
  "valid_samples": 757500,
  "candidate_shots_examined": 5,
  "excluded_candidates": 0,
  "computed_signals": 10,
  "inconclusive_signals": 0
}

Units: shots/signals/samples

Uncertainty: Missingness is counted; source calibration uncertainty unknown

Limits: Source Level2 diagnostic processing release retained; instrument/physics validation is not asserted.

MCF-02 / DERIVED

Temporal and spectral characterization of source measurements

Finite contiguous regular segments, SciPy FFT/Welch/STFT, explicit Hann/overlap/resolution, derivative excursions

[
  {
    "shot_id": 30421,
    "diagnostic": "magnetics/ip",
    "unit": "A",
    "rms": 592831.2924338278,
    "peak_hz": 19.53125000000215,
    "resolution_hz": 19.53125000000215,
    "candidate_events": 1
  },
  {
    "shot_id": 30421,
    "diagnostic": "magnetics/b_field_pol_probe_omv_voltage",
    "unit": "V",
    "rms": 0.006361044050117094,
    "peak_hz": 366.21093749963376,
    "resolution_hz": 122.07031249987791,
    "candidate_events": 0
  },
  {
    "shot_id": 30424,
    "diagnostic": "magnetics/ip",
    "unit": "A",
    "rms": 591866.5020935973,
    "peak_hz": 19.53125000000215,
    "resolution_hz": 19.53125000000215,
    "candidate_events": 2
  },
  {
    "shot_id": 30424,
    "diagnostic": "magnetics/b_field_pol_probe_omv_voltage",
    "unit": "V",
    "rms": 0.006344997549364238,
    "peak_hz": 244.14062499975583,
    "resolution_hz": 122.07031249987791,
    "candidate_events": 0
  },
  {
    "shot_id": 30417,
    "diagnostic": "magnetics/ip",
    "unit": "A",
    "rms": 595148.1644974579,
    "peak_hz": 19.53125000000215,
    "resolution_hz": 19.53125000000215,
    "candidate_events": 5
  },
  {
    "shot_id": 30417,
    "diagnostic": "magnetics/b_field_pol_probe_omv_voltage",
    "unit": "V",
    "rms": 0.006528670436586266,
    "peak_hz": 366.21093749963376,
    "resolution_hz": 122.07031249987791,
    "candidate_events": 1
  },
  {
    "shot_id": 30425,
    "diagnostic": "magnetics/ip",
    "unit": "A",
    "rms": 589717.8580495752,
    "peak_hz": 19.53125000000215,
    "resolution_hz": 19.53125000000215,
    "candidate_events": 3
  },
  {
    "shot_id": 30425,
    "diagnostic": "magnetics/b_field_pol_probe_omv_voltage",
    "unit": "V",
    "rms": 0.006353864079767064,
    "peak_hz": 122.07031249987791,
    "resolution_hz": 122.07031249987791,
    "candidate_events": 0
  },
  {
    "shot_id": 30426,
    "diagnostic": "magnetics/ip",
    "unit": "A",
    "rms": 591115.2138045023,
    "peak_hz": 19.53125000000215,
    "resolution_hz": 19.53125000000215,
    "candidate_events": 0
  },
  {
    "shot_id": 30426,
    "diagnostic": "magnetics/b_field_pol_probe_omv_voltage",
    "unit": "V",
    "rms": 0.0063830213630413895,
    "peak_hz": 366.21093749963376,
    "resolution_hz": 122.07031249987791,
    "candidate_events": 0
  }
]

Units: A/V,Hz,s

Uncertainty: Frequency-bin and time-grid resolution; window/filter/threshold sensitivity; no total calibration error

Limits: Peaks and transients are not identified MHD modes, ELMs or disruptions.

MCF-03 / STATISTICAL

Cross-shot spread and parameter sensitivity

Report all selected shots and all declared spectral/filter/event settings; same-shot descriptive correlation only

[
  {
    "diagnostic": "magnetics/ip",
    "unit": "A",
    "shot_ids": [
      30421,
      30424,
      30417,
      30425,
      30426
    ],
    "rms_distribution": {
      "n": 5,
      "mean": 592135.806175792,
      "std_sample": 2032.1546700068814,
      "rms": 592138.5958350777,
      "minimum": 589717.8580495752,
      "maximum": 595148.1644974579,
      "p05": 589997.3292005607,
      "p95": 594684.7900847319
    },
    "mean_distribution": {
      "n": 5,
      "mean": 584080.4758145832,
      "std_sample": 1817.180002365998,
      "rms": 584082.7372404691,
      "minimum": 581892.6515208334,
      "maximum": 586681.2878645833,
      "p05": 582139.4509083334,
      "p95": 586324.9120875
    },
    "dominant_frequency_distribution_hz": {
      "n": 5,
      "mean": 19.53125000000215,
      "std_sample": 0.0,
      "rms": 19.53125000000215,
      "minimum": 19.53125000000215,
      "maximum": 19.53125000000215,
      "p05": 19.53125000000215,
      "p95": 19.53125000000215
    },
    "event_counts": [
      {
        "shot_id": 30421,
        "count": 1
      },
      {
        "shot_id": 30424,
        "count": 2
      },
      {
        "shot_id": 30417,
        "count": 5
      },
      {
        "shot_id": 30425,
        "count": 3
      },
      {
        "shot_id": 30426,
        "count": 0
      }
    ],
    "shots_with_candidate_events": 4,
    "denominator_shots": 5,
    "interpretation": "Same catalog campaign/shape/current category, not controlled identical experiments; no phase alignment, performance ranking or causal inference."
  },
  {
    "diagnostic": "magnetics/b_field_pol_probe_omv_voltage",
    "unit": "V",
    "shot_ids": [
      30421,
      30424,
      30417,
      30425,
      30426
    ],
    "rms_distribution": {
      "n": 5,
      "mean": 0.006394319495775211,
      "std_sample": 7.641068882360629e-05,
      "rms": 0.006394684721606229,
      "minimum": 0.006344997549364238,
      "maximum": 0.006528670436586266,
      "p05": 0.006346770855444803,
      "p95": 0.006499540621877291
    },
    "mean_distribution": {
      "n": 5,
      "mean": 0.0063861650649483,
      "std_sample": 7.594009372340283e-05,
      "rms": 0.006386526266683157,
      "minimum": 0.006337163139544427,
      "maximum": 0.006519698751034836,
      "p05": 0.006338926882321636,
      "p95": 0.0064907346341883145
    },
    "dominant_frequency_distribution_hz": {
      "n": 5,
      "mean": 292.96874999970703,
      "std_sample": 109.18300671374774,
      "rms": 308.81617775050944,
      "minimum": 122.07031249987791,
      "maximum": 366.21093749963376,
      "p05": 146.48437499985351,
      "p95": 366.21093749963376
    },
    "event_counts": [
      {
        "shot_id": 30421,
        "count": 0
      },
      {
        "shot_id": 30424,
        "count": 0
      },
      {
        "shot_id": 30417,
        "count": 1
      },
      {
        "shot_id": 30425,
        "count": 0
      },
      {
        "shot_id": 30426,
        "count": 0
      }
    ],
    "shots_with_candidate_events": 1,
    "denominator_shots": 5,
    "interpretation": "Same catalog campaign/shape/current category, not controlled identical experiments; no phase alignment, performance ranking or causal inference."
  }
]

Units: A/V,Hz,counts

Uncertainty: Observed cross-shot dispersion and method sensitivity; small selected cohort, not population inference

Limits: Differences may reflect unmeasured experimental settings or processing; no causal plasma conclusion.

Measurements and comparisons

ShotDiagnosticN / validUnitRMSPeak / HzResolution / HzEvents
30421magnetics/ip1500 / 1500A592831.292433827819.5312500000021519.531250000002151
30421magnetics/b_field_pol_probe_omv_voltage150000 / 150000V0.006361044050117094366.21093749963376122.070312499877910
30424magnetics/ip1500 / 1500A591866.502093597319.5312500000021519.531250000002152
30424magnetics/b_field_pol_probe_omv_voltage150000 / 150000V0.006344997549364238244.14062499975583122.070312499877910
30417magnetics/ip1500 / 1500A595148.164497457919.5312500000021519.531250000002155
30417magnetics/b_field_pol_probe_omv_voltage150000 / 150000V0.006528670436586266366.21093749963376122.070312499877911
30425magnetics/ip1500 / 1500A589717.858049575219.5312500000021519.531250000002153
30425magnetics/b_field_pol_probe_omv_voltage150000 / 150000V0.006353864079767064122.07031249987791122.070312499877910
30426magnetics/ip1500 / 1500A591115.213804502319.5312500000021519.531250000002150
30426magnetics/b_field_pol_probe_omv_voltage150000 / 150000V0.0063830213630413895366.21093749963376122.070312499877910

Original scientific visualizations

MAST 30421 / magnetics/ip / A; quality/segment/filter parameters in JSON. Signal-processing features are not identified plasma modes.
MAST 30421 / magnetics/ip / A; quality/segment/filter parameters in JSON. Signal-processing features are not identified plasma modes.
MAST 30421 / magnetics/b_field_pol_probe_omv_voltage / V; quality/segment/filter parameters in JSON. Signal-processing features are not identified plasma modes.
MAST 30421 / magnetics/b_field_pol_probe_omv_voltage / V; quality/segment/filter parameters in JSON. Signal-processing features are not identified plasma modes.
MAST 30424 / magnetics/ip / A; quality/segment/filter parameters in JSON. Signal-processing features are not identified plasma modes.
MAST 30424 / magnetics/ip / A; quality/segment/filter parameters in JSON. Signal-processing features are not identified plasma modes.
MAST 30424 / magnetics/b_field_pol_probe_omv_voltage / V; quality/segment/filter parameters in JSON. Signal-processing features are not identified plasma modes.
MAST 30424 / magnetics/b_field_pol_probe_omv_voltage / V; quality/segment/filter parameters in JSON. Signal-processing features are not identified plasma modes.
MAST 30417 / magnetics/ip / A; quality/segment/filter parameters in JSON. Signal-processing features are not identified plasma modes.
MAST 30417 / magnetics/ip / A; quality/segment/filter parameters in JSON. Signal-processing features are not identified plasma modes.
MAST 30417 / magnetics/b_field_pol_probe_omv_voltage / V; quality/segment/filter parameters in JSON. Signal-processing features are not identified plasma modes.
MAST 30417 / magnetics/b_field_pol_probe_omv_voltage / V; quality/segment/filter parameters in JSON. Signal-processing features are not identified plasma modes.
MAST 30425 / magnetics/ip / A; quality/segment/filter parameters in JSON. Signal-processing features are not identified plasma modes.
MAST 30425 / magnetics/ip / A; quality/segment/filter parameters in JSON. Signal-processing features are not identified plasma modes.
MAST 30425 / magnetics/b_field_pol_probe_omv_voltage / V; quality/segment/filter parameters in JSON. Signal-processing features are not identified plasma modes.
MAST 30425 / magnetics/b_field_pol_probe_omv_voltage / V; quality/segment/filter parameters in JSON. Signal-processing features are not identified plasma modes.
MAST 30426 / magnetics/ip / A; quality/segment/filter parameters in JSON. Signal-processing features are not identified plasma modes.
MAST 30426 / magnetics/ip / A; quality/segment/filter parameters in JSON. Signal-processing features are not identified plasma modes.
MAST 30426 / magnetics/b_field_pol_probe_omv_voltage / V; quality/segment/filter parameters in JSON. Signal-processing features are not identified plasma modes.
MAST 30426 / magnetics/b_field_pol_probe_omv_voltage / V; quality/segment/filter parameters in JSON. Signal-processing features are not identified plasma modes.

Uncertainty, discussion and limitations

Validation and conclusions

Algorithm controls, independent numerical checks and exact acquired-source replay accompany publication. These are reproducible descriptions of selected real data, not a new plasma law, named instability, ignition result or validated prediction.

eda30cddda1943f19425d2b9472d4e773f62c100e298191538fee6b13330a8bd

Sources, data license and attribution

Original software: Apache2.0. Data-derived scientific report, plots and selected measurements: CC-BY-SA-4.0. Source attribution and modifications: acquired source arrays, unit normalization, explicit selections, deterministic statistics and labeled display scaling by Mattoccia Labs; no source endorsement.

Reproduction

# Reproduce FPE-001

From the original source release, on qualified macOS Apple Silicon/Python3.12:

```sh
python3.12 scripts/setup_fusion.py
.venv-fpre/bin/python -m fusion.cli run --experiment FPE-001 --data .local/fusion
.venv-fpre/bin/python -m fusion.cli reproduce --experiment FPE-001 --job JOB_ID --data .local/fusion
```

Initial run acquires official data explicitly. Keep source responses and manifest. Reproduce rehashes original bytes and recomputes without network; missing or modified source objects cause a visible failure. Upstream may replace Zarr objects at the same URL, so fresh acquisition is not automatically the original version. A qualified selected-input public replay is separately labeled; it cannot replace full raw-source validation. No model, apparatus access or cloud is required. Other operating systems are not qualified.