Alice Weekly Meeting: Software for Hardware Accelerators

Wednesday 3 Sept 2025, 10:00 → 11:00 Europe/Zurich

10:00 → 10:20 Discussion

Speaker: David Rohr (CERN)

10:20 → 10:25 TPC ML Clustering

Speaker: Christian Sonnabend (CERN, Heidelberg University (DE))

Investigating ITS-TPC matching (in)efficiency

• Selected were primaries with NCL > 60. Problem: Lower efficiency for NN regression algortihm, independent of cluster classification threshold.

 

Investigation of NN and CF regression performance

• CF regression finds more TPC tracks (0.15%) while NN regression produces more clusters (0.52%)

• CF[60:]-NN[60:] = -609    -> NN finds more tracks with NCL > 60
• CF[:60]-NN[:60] = 8955   -> CF finds a lot more short tracks that are not used in physics
• NN regression potentially reduces NCL for tracks with high NCL. For large clusters, a more accurate CoG will be "further away". Such clusters are actually bad -> get excluded in dE/dx calculation by truncated mean

 

Back to ITS-TPC matching:

• Number of found matches: 1.3% less matches for NN (global, no selection)
•  

10:25 → 10:30 GPU Parameter Optimizations

Speaker: Gabriele Cimador (CERN, Università and INFN Torino)

10:30 → 10:35 Efficient Data Structures

Speaker: Dr Oliver Gregor Rietmann (CERN)

10:35 → 10:40 Following up GPU to-dos

Speaker: Dr Vikas Singhal (Department of Atomic Energy (IN))

10:40 → 10:45 TPC Clusterization / OpenCL / Highly Ionizing Particles

Speaker: Felix Weiglhofer (Goethe University Frankfurt (DE))

10:45 → 10:50 ITS Tracking

Speakers: Felix Schlepper (CERN, Heidelberg University (DE)), Gabriele Cimador (CERN, Università and INFN Torino), Matteo Concas (CERN)

10:50 → 10:55 System Run Coordination Topics

Speaker: Ernst Hellbar (CERN)