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Time-series photometry

The Time-Series Photometry Tool performs differential photometry across a stack of exposures to produce light curves for one or more target objects. It's the go-to tool for variable-star work, exoplanet transit photometry, asteroid rotation curves, and anything else where you need a calibrated flux-vs-time series.

Status: the data model for this tool is in place (TimeSeriesPhotometryTool and related records) and the API surfaces it through time_series_photometry_tools in public-api, but a dedicated React-port page is not yet in. For hands-on use today, the easiest paths are Afterglow (custom photometry) or Astromancer (guided coursework). This page will be updated when an in-app route lands.

When to use it

Use this tool when you have:

  • A series of optical imaging observations of the same field across time.
  • One or more target sources whose flux you want measured against one or more comparison sources.
  • A consistent enough setup (same filter, same instrument) that differential photometry makes sense.

Inputs and outputs

Inputs:

  • An ordered set of exposure files from one or more observations on the same field.
  • The target object(s) — coordinates plus a name.
  • Comparison object(s) — used as the photometric reference.
  • Aperture and annulus settings — initial aperture radius, inner / outer sky annulus, optional ellipticity and position angle.

Outputs:

  • A TimeSeriesPhotometryToolResult record per source per exposure, with time, flux, flux error, magnitude, magnitude error, centroid, aperture geometry, background statistics, and saturation flags.
  • Light curves you can export for further analysis.
  • Stack files (TimeSeriesPhotometryStackFile) that bundle the measured exposures for reproducibility.

Reference

The data model for the tool's inputs, intermediate state, and output: