Waveform MAGIC Telescope Data With Graph Neural Networks

Jarred Green

Geneva, ICRC 2025

20 August 2025

Max Planck Institute for Physics

jgreen@mpp.mpg.de

Outline

  1. Current Reconstruction Method
  2. Graphs
  3. The Data
  4. ML Playground
  5. Conclusions

Jarred Green - jgreen@mpp.mpg.de

1. Current Reconstruction

Jarred Green - jgreen@mpp.mpg.de

{
	'size': 546.8863769783503,
	'xc': -3.7898364035228065,
	'yc': 7.294274369102854,
	'length': 7.767692666363586,
	'width': 1.7648053936769377,
	'delta': -0.5687518727314761,
	 ...
}

tl;dr

  • Particle Type
  • Energy
  • Arrival Direction

ML

1. Current Reconstruction

1039 \ \text{pixels} \\ \times 50 \ \text{time slices} \\ \times 2 \ \text{telescopes} \\ = 103900 \ \text{data points}

tl;dr

1. Current Reconstruction

1039 \ \text{pixels} \\ \times 50 \ \text{time slices} \\ \times 2 \ \text{telescopes} \\ = 103900 \ \text{data points}

Why Deep Learning?

  • Fast on-site inference
  • Handles multiple analysis configurations with ease

Jarred Green - jgreen@mpp.mpg.de

A way to include as much information as possible?

1. Current Reconstruction

Jarred Green - jgreen@mpp.mpg.de

Proton

Gamma

Muon

Find a new ways to represent 'raw' data

1. Current Reconstruction

Why waveform data?

  • Contains full time evolution of event
  • Traditionally too data-heavy to consider

2. Graphs

Jarred Green - jgreen@mpp.mpg.de

Jarred Green - jgreen@mpp.mpg.de

Lets go from images

to graphs

Credit: J. Leskovec (Stanford CS224)

Graphs can effectively deal with:

  • irregular camera geometry
  • sparse data
  • non gridlike pixels
  • arrays with different cameras (ie CTA)
  • information on each node (pixel) and edge (connection)

Jarred Green - jgreen@mpp.mpg.de

Why Graphs?

Jarred Green - jgreen@mpp.mpg.de

time

  • Sample MC gama 
  • ⏳ Training ~days

2. Graphs

Jarred Green - jgreen@mpp.mpg.de

time

Can we make these graphs smaller somehow?

cleaning!

  • ✅ Small graphs with 200-2K nodes
  • ✅ Training ~hours

2. Graphs

Jarred Green - jgreen@mpp.mpg.de

Goal: get calibrated data with timing information

Python package magic-gnn

.parquet or LMDB files exported, about ~1GB / min of data

Python package magic-gnn

3. Data

GNN with
calibrated graphs

1️⃣

Transformers
+ GNNs

2️⃣

Jarred Green - jgreen@mpp.mpg.de

3. Data

Training Data:

  • 2.5M MC events
  • 50/50 gamma-ray / proton split
  • GNN framework for Neutrino reconstruction
  • 15-20% improvement in reconstruction of energy, zenith, direction at low energies

Jarred Green - jgreen@mpp.mpg.de

4. Playground

✅ Particle ID classification

Model:

  • Binary classification task
  • DynEdge with 12 NN
  • Separate in each telescope
  • Cross-attention 
  • Only need 5-10% of training data

GNN with
calibrated graphs

1️⃣

Jarred Green - jgreen@mpp.mpg.de

4. Playground

✅ Direction reconstruction

In progress:

  • Direction classification
  • Testing a combination of GNNs with DynEdge and transformers
  • Adapted from IceCube's most robust direction reconstruction models

chatbots 🤖

MC 68% containment < 0.08deg

Transformers
+ GNNs

2️⃣

Jarred Green - jgreen@mpp.mpg.de

5. Conclusions

Deep Learning

  • Fast analysis with GPUs

  • Deep models can handle multiple analysis settings

Graph Networks

  • Handle irregular camera geometries
  • Manages multiple different telescopes

Waveform Data

  • Contains full time evolution
  • Can save on data processing

Thank you!

Jarred Green - jgreen@mpp.mpg.de

Credit: G. Ceribella

ICRC 2025 - MAGIC Waveform DL

By astrojarred

ICRC 2025 - MAGIC Waveform DL

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