spotter

Approximate forward models of fluxes and spectra time-series of non-uniform stars.

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spotter serves as a flexible, low-level backend for scientific applications that require modeling stellar surfaces using spherical pixelation. While it is not a comprehensive simulation suite like StarSim or SOAP, spotter provides core building blocks for custom workflows, including:

• Modeling surface features (e.g., stellar spots or faculae) with arbitrary shapes

• Forward modeling of stellar surface flux, spectra, radial velocities, and CCFs

• Simulation of observables during transits by stellar or planetary companions

• Gaussian process frameworks for representing stellar surfaces and modeling their flux time series

spotter uses the HEALPix subdivision scheme and is powered by the high-performance numerical package JAX, enabling its use on multiple CPUs and accelerators like GPUs and TPUs.

Get started

• Installation
• Introduction
• Precision & speed

Tutorials

• Surface Gaussian Process
• Flux Gaussian Process
• Doppler maps
• Multi-band light curves
• Spot occultation
• Radial Velocity

Reference

• Principle
• API Reference