Run Outputs and Records

Every skasim execution produces a structured set of outputs designed for both automated parsing and human review.

Output Directory Structure

By default, the output is stored in a directory named: YYYYMMDD_HHMMSS_<telescope> (e.g., 20260604_143005_SKA1MID).

Within this directory, you will find:

  • manifest.json: The root structured record of the run.

  • weblog.html: A self-contained HTML report for visual review.

  • work_dir/: Intermediate files, including run-local CASA image copies and MS files.

  • skasim_casa_*.log: Detailed logs from CASA batch executions.

The Manifest (manifest.json)

The manifest is the canonical “truth” of a simulation run. It is a JSON file containing:

  • Config: A copy of the SimConfig used for the run.

  • Milestones: A chronological list of high-level pipeline events.

  • Outputs: Paths to all generated products (images, MS, logs).

Milestones

Milestones provide an audit trail. For example, the adjusted_spectral_reference milestone records how an input image model was scaled:

{
  "name": "adjusted_spectral_reference",
  "status": "completed",
  "timestamp": "2026-06-04T12:00:00.000000",
  "details": {
    "model_type": "casa_taylor_terms",
    "old_reference_frequency_hz": 5991892258.0,
    "new_reference_frequency_hz": 1284000000.0,
    "nterms": 2
  }
}

The Weblog

The Weblog is a self-contained HTML report generated after each run. It is a single file: weblog.html located in the run’s output directory. Open it in any modern browser to view the simulation summary.

Key Sections

  1. Sky Model: - Lists all ingested models. - Shows provenance (original file paths). - Provides visual previews. For CASA Taylor-term models, the tt0 term is automatically exported to FITS/PNG for display.

  2. Observation Details: - Spectral grid setup. - Phase center and telescope configuration.

  3. Injected Visibility Data: - Identifies the backend used for injection and model provenance.

  4. Imaging Results: - One dedicated section per imaging tag for multi-imaging runs. - Image previews for each available product (e.g., oskar-dirty and wsclean). - If enabled, UV Coverage plots (produced via shadeMS).

  5. Logs: - Filterable view of the pipeline logs. - Access to raw CASA logs (skasim_casa_*.log files).

HTML Report

The weblog.html file is a single, self-contained HTML file. It does not require a server; all CSS and images are embedded in the final report. This makes it trivial to archive or share.

Visibility Data (Measurement Set)

The resulting Measurement Set (.ms) is located within the output directory. It contains the combined visibilities from all sky models, ready for further processing with standard radio-interferometry tools.