`vacuum_to_air`¶

Convert the wavelength axis from vacuum to air wavelengths.


Category	Corrections
Backend	`numpy` - implemented here on top of numpy primitives
Version	`1.0.1`
Reads	`ctx.spectrum` (a `Spectrum1D`)
Writes	`spectrum`

n(λ_vac) = 1 + 8.34254e-5 + 2.406147e-2/(130 - s²) + 1.5998e-4/(38.9 - s²), s = 1e4/λ[Å] (Morton 2000). Valid above ~2000 Å.

Parameters¶

This algorithm takes no parameters.

PythonCLIMCP

from spectro_kernel import run_algorithm

output = run_algorithm("vacuum_to_air", ctx, {})

spectro run vacuum_to_air --input spectrum.fits

{
  "tool": "vacuum_to_air",
  "arguments": {
    "session_id": "<session_id>",
    "params": {}
  }
}

Every algorithm is an MCP tool of the same name; describe_algorithm returns this page's metadata as JSON.

air_to_vacuum - Convert the wavelength axis from air to vacuum wavelengths.
barycentric_correction - Compute the barycentric (or heliocentric) correction and Julian date, and shift the spectrum.
doppler_shift - Doppler-shift the wavelength axis by a radial velocity.
extinction_correct_easyspec - Apply atmospheric extinction correction to ctx.spectrum via easyspec.
fit_telluric_scaling - Fit the airmass that best matches a telluric template to ctx.spectrum.
remove_telluric_division - Remove telluric absorption by dividing the science spectrum by a reference.
synth_telluric - Generate a synthetic telluric transmission spectrum.