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rv_quick

Quick radial-velocity measurement from H-alpha on an already-loaded spectrum: normalise the continuum, then fit the line and turn its centroid shift into a velocity in km/s.
Kind analysis
Status reference - reviewed and adopted as the reference way to make this measurement
Version 1.0.0
Source bundled

Variables

This recipe declares no variables: it runs as is.

Steps

# Algorithm Parameters
1 normalize_polynomial Normalise continuum order=3, sigma_clip=3.0
2 measure_radial_velocity Measure radial velocity from H-alpha rest_wavelength_angstrom=6562.79, window_angstrom=30.0

Run it

spectro pipeline rv_quick --input spectrum.fits
spectro preset show rv_quick      # variables and steps

from spectro_kernel import WorkContext
from spectro_kernel.pipeline import PipelineBuilder

pipeline = PipelineBuilder().from_preset("rv_quick").build()
result = pipeline.execute(ctx)        # ctx holds the spectrum / frames
print(result.history[-1])             # pipeline:<name> vX.Y.Z + variables

{
  "tool": "run_preset",
  "arguments": {
    "session_id": "<session_id>",
    "preset_name": "rv_quick"
  }
}