Running

Table of Contents

• The pipeline
• The other binaries
• Where output goes
• Caching

The pipeline

The main entry point is the pipeline. For each CoMPASS binary subfile it runs: binary → raw hits → multi-board timing alignment → GPU timestamp sort → event building → beam-energy calibration → trace creation.

It processes the dataset's files — selected by RUNS and N_CHUNKS in analysis/<dataset>/config/Constants.cpp — in parallel, logging to analysis/<dataset>/pipeline_fused.log.

nix build .#87Rb
nix develop .#87Rb
./result/bin/pipeline

Note

The binaries take no command-line arguments. Every knob lives in Constants.hpp / Constants.cpp and in the control/ TOMLs. Each binary resolves its dataset directory at build time and cross-checks the dataset name if MUSIC_DATASET_DIR is overridden.

The other binaries

These operate on the pipeline's output ROOT files, and are all in ./result/bin/ after nix build .#<dataset>:

• calibrate-beam — per-channel beam-peak calibration, left/right gain matching, strip alignment, energy-resolution aggregation.
• strip-sum-scatter — reaction-strip scatter and dE plots, trace region overlays, comparisons against simulation.
• split-sol, preprocess-sol — the SOL-processing tools.

Where output goes

Generated data — event ROOT files and plots — is written to MUSIC_RESULTS_DIR when that is set, and otherwise to the baked-in dataset directory. The pipeline log always goes to <dataset dir>/pipeline_fused.log.

Running from the dev shell points both MUSIC_DATASET_DIR and MUSIC_RESULTS_DIR at the in-repo analysis/<dataset>, which is writable. Override MUSIC_RESULTS_DIR to send output to a scratch drive instead.

Caching

strip-sum-scatter caches its scatters and trace reservoir to analysis/<dataset>/root_files/StripSumScatter_cache.root.

The cache carries a fingerprint of every configuration knob that changes its contents — filters, gates, strip spans, and so on — so editing any of them rebuilds the cache automatically on the next run. There is no cache-clearing step to remember.