Attenuator plate correction#

Summary#

Apply angle-dependent attenuator plate transmission.

Metadata#

Module ID: AttenuatorPlateCorrection
Module path: /home/runner/work/MoDaCor/MoDaCor/src/modacor/modules/technique_modules/scattering/attenuator_plate_correction.py
Module version: 20260902.1
Keywords: attenuator, plate, attenuation, absorption, transmission

Required data keys#

signal
CosAlpha

Modifies#

signal: signal, uncertainties

Required arguments#

with_processing_keys

Default configuration#

{
  "apply_as": "divide",
  "beam_energy": null,
  "beam_energy_source": null,
  "beam_energy_units": "keV",
  "beam_energy_units_source": null,
  "chemical_composition": null,
  "chemical_composition_source": null,
  "correction_key": "attenuator_transmission",
  "cos_alpha_key": "CosAlpha",
  "density": null,
  "density_source": null,
  "density_units": "g/cm^3",
  "density_units_source": null,
  "linear_attenuation_coefficient": null,
  "linear_attenuation_coefficient_source": null,
  "linear_attenuation_coefficient_units": "1/m",
  "linear_attenuation_coefficient_units_source": null,
  "material": null,
  "material_source": null,
  "minimum_cos_alpha": 1e-12,
  "normalize_to_normal_incidence": false,
  "thickness": null,
  "thickness_source": null,
  "thickness_units": "m",
  "thickness_units_source": null,
  "wavelength": null,
  "wavelength_source": null,
  "wavelength_units": "angstrom",
  "wavelength_units_source": null,
  "with_processing_keys": [
    "sample"
  ]
}

Argument specification#

Argument	Type	Required	Default	Dependency role	Description
`apply_as`	str	No	divide	-	Apply the transmission map by ‘divide’ for correction or ‘multiply’ for DAWN-style attenuation.
`beam_energy`	int or float or NoneType	No	-	-	Incident beam energy.
`beam_energy_source`	str or NoneType	No	-	-	Optional IoSources key for incident beam energy.
`beam_energy_units`	str	No	keV	-	Units for beam_energy.
`beam_energy_units_source`	str or NoneType	No	-	-	Optional IoSources key for beam energy units.
`chemical_composition`	str or NoneType	No	-	-	Alias for material.
`chemical_composition_source`	str or NoneType	No	-	-	Optional IoSources key for chemical_composition.
`correction_key`	str	No	attenuator_transmission	-	BaseData key used to store the applied transmission map.
`cos_alpha_key`	str	No	CosAlpha	-	BaseData key containing the incidence cosine n dot rhat.
`density`	int or float or NoneType	No	-	-	Attenuator material density.
`density_source`	str or NoneType	No	-	-	Optional IoSources key for attenuator density.
`density_units`	str	No	g/cm^3	-	Units for density.
`density_units_source`	str or NoneType	No	-	-	Optional IoSources key for density units.
`linear_attenuation_coefficient`	int or float or NoneType	No	-	-	Optional direct linear attenuation coefficient.
`linear_attenuation_coefficient_source`	str or NoneType	No	-	-	Optional IoSources key for a direct linear attenuation coefficient.
`linear_attenuation_coefficient_units`	str	No	1/m	-	Units for linear_attenuation_coefficient.
`linear_attenuation_coefficient_units_source`	str or NoneType	No	-	-	Optional IoSources key for linear attenuation coefficient units.
`material`	str or NoneType	No	-	-	Attenuator material formula or element symbol, used with xraylib lookup.
`material_source`	str or NoneType	No	-	-	Optional IoSources key for attenuator material formula or element symbol.
`minimum_cos_alpha`	int or float	No	1e-12	-	Lower numerical clip for positive cos_alpha values.
`normalize_to_normal_incidence`	bool	No	False	-	If true, divide by transmission(cos_alpha) / transmission(cos_alpha=1).
`thickness`	int or float or NoneType	No	-	-	Attenuator thickness.
`thickness_source`	str or NoneType	No	-	-	Optional IoSources key for attenuator thickness.
`thickness_units`	str	No	m	-	Units for thickness.
`thickness_units_source`	str or NoneType	No	-	-	Optional IoSources key for thickness units.
`wavelength`	int or float or NoneType	No	-	-	Incident wavelength, used to derive beam energy if beam_energy is not configured.
`wavelength_source`	str or NoneType	No	-	-	Optional IoSources key for incident wavelength.
`wavelength_units`	str	No	angstrom	-	Units for wavelength.
`wavelength_units_source`	str or NoneType	No	-	-	Optional IoSources key for wavelength units.
`with_processing_keys`	list	Yes	[“sample”]	-	ProcessingData keys whose signal should be corrected.

Notes#

Material parameters can be provided as direct values or *_source paths. xraylib is used for material lookup unless linear_attenuation_coefficient is configured directly. The default applies a physical correction by dividing by transmission; apply_as=’multiply’ is provided for DAWN cross-validation where the recorded operation applies the attenuation factor itself.

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