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Foundations

  • Quickstart
  • Why JAX
  • SED Anatomy
  • Discovering the Menu
  • Building Models

Fitting workflows

  • Fitting Photometry
  • Fitting Spectroscopy
  • Joint Photometry + Spectroscopy

Physics deep dives

  • Emission Lines
  • 09_parameter_sweeps

Reference

  • Performance
  • Memory expectations
  • Units and conventions

Gallery

  • Advanced Topics
    • Age-Dust-Metallicity Degeneracy: Fisher Analysis
    • Gradient Sensitivity Heatmap
    • Hierarchical PSD Inference
    • Joint Photometry + Spectroscopy Fit
    • Component orchestrator end-to-end
    • Panchromatic SED: UV to Radio
  • AGN Models
    • X-ray Corona: Spectral Index vs Bolometric Luminosity 2D Sweep
    • SKIRTOR Torus: Viewing Angle Sweep
    • AGN SEDModel Hierarchy
    • QSOgen Disc Continuum: Bolometric Luminosity
    • SKIRTOR Torus: Opening Angle Sweep
    • Polar Dust: Temperature Sweep in AGN Torus
    • QSOgen Dust Reddening: Intrinsic AGN Obscuration
    • QSOgen Emission Line Scaling: Rest-UV to Optical SED
    • SKIRTOR Torus: Radial Dust Power-Law Sweep
    • SKIRTOR Torus: Optical Depth Sweep
    • AGN SED Templates
    • Type 1 vs Type 2 AGN: Geometric Unification
    • Narrow and Broad Line Region Emission
    • Polar Dust in AGN: IR Bump from Polar Dust Torus
    • QSOgen Empirical Quasar Template
    • RELAGN Spin Sweep
    • SKIRTOR Clumpy Torus: Inclination and Optical Depth
    • Torus Models Comparison: Nenkova vs Silva04
  • Hensley & Draine 2023 Astrodust+PAH
    • Astrodust+PAH size distribution
    • Astrodust+PAH emission vs log U
    • Astrodust+PAH per-component decomposition
    • DustEmissionSEDComponent — swap MBB / PAHspec / Astrodust
    • Astrodust+PAH ionization fraction and alignment
    • Astrodust+PAH extinction, scattering, and albedo
    • Astrodust+PAH spinning-dust microwave emission
    • Astrodust+PAH polarized emission and polarization fraction
  • Dust Models
    • Hensley & Draine 2023 Astrodust+PAH: log U sweep
    • Attenuation Law Comparison
    • BOSA: log L_TIR sweep at fixed log sSFR
    • BOSA: log sSFR sweep at fixed log L_TIR
    • Modified Blackbody Dust Temperature
    • Dust Attenuation Curves
    • Dust Emission Models: Overview
    • Dust Geometry: Screen vs Mixed vs Clumpy
    • Dust IR SED: q_PAH × U_min Grid
    • Attenuation Curve Slope (δ)
    • Draine+2021 PAHspec: log U sweep at fixed (starlight, ion, size)
    • Draine+2021 PAHspec: starlight-spectrum sweep at fixed log U
    • PAH Mass Fraction (q_PAH)
    • Birth Cloud Optical Depth (τ_BC)
    • Diffuse ISM Optical Depth (τ_diff)
    • THEMIS: q_HAC sweep at fixed U_min
    • THEMIS: U_min sweep at fixed q_HAC
    • Two-Component Dust SEDModel
    • Draine & Li Minimum Radiation Field (U_min)
    • UV Bump Strength (dust_bump_strength)
  • IGM
    • Damped Lyman-Alpha (DLA) Absorption
    • IGM Transmission Model Comparison
    • IGM Transmission vs Redshift
    • IGM Absorption Evolution with Redshift
  • Inference Methods
    • Convergence Diagnostics
    • Corner Plot with Truth Overlay
    • Population PSD Recovery: 1/√N Convergence
    • MAP vs geoVI Posterior Comparison
    • Population VI scaling: time, memory, and convergence
    • Prior vs Posterior: Parameter Constraints from Inference
  • Metallicity
    • α/Fe Enhancement (met_alpha_fe)
    • Metallicity Sweep: Panchromatic SED
    • Stellar Metallicity (log Z/Z_⊙)
    • Stellar Continuum: Metallicity × Age Grid
    • Chemical Evolution: Model Comparison
  • Multiwavelength
    • FIR–Radio Correlation
    • Panchromatic AGN Host SED
    • AGN Contribution to Composite SEDs
    • Dust Energy Balance: UV Attenuation ↔ IR Emission
    • Panchromatic Star-Forming Galaxy
    • Panchromatic SED: Redshift Evolution
  • Nebular Emission
    • BPT with Cue: Every Knob, One Panel Each
    • BPT Diagrams with Cue: 2D Grid in (log U, log Z_gas)
    • BPT Diagnostics: Star Formation, Shocks, and AGN
    • Diffuse Ionized Gas Fraction (f_DIG)
    • Ionizing Photon Escape Fraction (f_esc)
    • Emission Line Width (σ in km/s)
    • Ionization Parameter (logU)
    • Gas Metallicity (log Z/Zsun)
    • Nebular Emission: Dependence on Stellar Population Age
    • Nebular Backends: BakedIn vs CloudyGrid vs Cue
    • BPT Diagram: Ionization Parameter Sequence
    • Nebular Gas Density: Metallicity Variation
    • Nebular Emission Backends
    • Nebular Shock Emission (MAPPINGS V)
  • Photometry
    • SDSS Filter Transmission Curves
    • Filter Set Comparison
    • Photometric SED Fit
    • Filter Sampling Across Redshift
    • S/N Ratio Parameter Sweep
  • Quick Start
    • First Photometric Fit
    • SED Components
  • Radio
    • Radio Spectral Index (α_sf)
    • FIR-Radio Correlation (q_IR)
    • FIR-Radio Correlation: L_IR Luminosity Sweep
    • AGN Radio Loudness (R)
  • Star Formation Histories
    • SFH Recovery Across Four Burstiness Regimes
    • Chemical Evolution: Metallicity History Models
    • Delayed-τ SFH: Star Formation Timescale
    • Double Power-Law SFH: 2D Parameter Grid (α × β)
    • Double Power-Law SFH: Rising Slope α
    • Double Power-Law SFH: Falling Slope β
    • Log-Normal SFH: Peak Lookback Time
    • Parametric SFH Models
    • Alternative PSD Models
    • PSD Parameter Space and Burstiness
    • Stochastic SFH: Burstiness Amplitude σ
    • Stochastic SFH: Burstiness Timescale τ
    • SFH with Double Bursts: Old and Recent Star Formation
    • SFH Quenching Scenarios: Constant, Exponential, Sharp, and Burst+Decay
    • Stochastic SFH from GP Correlated Fields
    • The Wrong-SEDModel Trap: Parametric Bias in Derived Quantities
  • Spectroscopy
    • Instrumental Resolution Sweep
    • Key Spectral Features as Age and Metallicity Probes
    • Spectroscopic SED Fit
    • Stellar Velocity Dispersion Sweep
  • Stellar Population Synthesis
    • Stellar Population Aging: SSP at Solar Metallicity
    • SSP Grid Visualization: Age and Metallicity
    • IMF Comparison: Mass-to-Light Ratio
    • Stellar Metallicity Effects on SED
  • X-ray Emission
    • High-Energy Cutoff Variation
    • X-ray Normalisation via UV-to-X-ray Slope
    • AGN X-ray Emission and Corona
    • X-ray Spectral Index Variation
    • X-ray Binary Population from Star Formation
  • Examples gallery
  • Advanced Topics
  • AGN Models
  • Hensley & Draine 2023 Astrodust+PAH
  • Dust Models
  • IGM
  • Inference Methods
  • Metallicity
  • Multiwavelength
  • Nebular Emission
  • Photometry
  • Quick Start
  • Radio
  • Star Formation Histories
  • Spectroscopy
  • Stellar Population Synthesis
  • X-ray Emission
  • Examples gallery
    • Advanced Topics
      • Age-Dust-Metallicity Degeneracy: Fisher Analysis
      • Gradient Sensitivity Heatmap
      • Hierarchical PSD Inference
      • Joint Photometry + Spectroscopy Fit
      • Component orchestrator end-to-end
      • Panchromatic SED: UV to Radio
    • AGN Models
      • X-ray Corona: Spectral Index vs Bolometric Luminosity 2D Sweep
      • SKIRTOR Torus: Viewing Angle Sweep
      • AGN SEDModel Hierarchy
      • QSOgen Disc Continuum: Bolometric Luminosity
      • SKIRTOR Torus: Opening Angle Sweep
      • Polar Dust: Temperature Sweep in AGN Torus
      • QSOgen Dust Reddening: Intrinsic AGN Obscuration
      • QSOgen Emission Line Scaling: Rest-UV to Optical SED
      • SKIRTOR Torus: Radial Dust Power-Law Sweep
      • SKIRTOR Torus: Optical Depth Sweep
      • AGN SED Templates
      • Type 1 vs Type 2 AGN: Geometric Unification
      • Narrow and Broad Line Region Emission
      • Polar Dust in AGN: IR Bump from Polar Dust Torus
      • QSOgen Empirical Quasar Template
      • RELAGN Spin Sweep
      • SKIRTOR Clumpy Torus: Inclination and Optical Depth
      • Torus Models Comparison: Nenkova vs Silva04
    • Hensley & Draine 2023 Astrodust+PAH
      • Astrodust+PAH size distribution
      • Astrodust+PAH emission vs log U
      • Astrodust+PAH per-component decomposition
      • DustEmissionSEDComponent — swap MBB / PAHspec / Astrodust
      • Astrodust+PAH ionization fraction and alignment
      • Astrodust+PAH extinction, scattering, and albedo
      • Astrodust+PAH spinning-dust microwave emission
      • Astrodust+PAH polarized emission and polarization fraction
    • Dust Models
      • Hensley & Draine 2023 Astrodust+PAH: log U sweep
      • Attenuation Law Comparison
      • BOSA: log L_TIR sweep at fixed log sSFR
      • BOSA: log sSFR sweep at fixed log L_TIR
      • Modified Blackbody Dust Temperature
      • Dust Attenuation Curves
      • Dust Emission Models: Overview
      • Dust Geometry: Screen vs Mixed vs Clumpy
      • Dust IR SED: q_PAH × U_min Grid
      • Attenuation Curve Slope (δ)
      • Draine+2021 PAHspec: log U sweep at fixed (starlight, ion, size)
      • Draine+2021 PAHspec: starlight-spectrum sweep at fixed log U
      • PAH Mass Fraction (q_PAH)
      • Birth Cloud Optical Depth (τ_BC)
      • Diffuse ISM Optical Depth (τ_diff)
      • THEMIS: q_HAC sweep at fixed U_min
      • THEMIS: U_min sweep at fixed q_HAC
      • Two-Component Dust SEDModel
      • Draine & Li Minimum Radiation Field (U_min)
      • UV Bump Strength (dust_bump_strength)
    • IGM
      • Damped Lyman-Alpha (DLA) Absorption
      • IGM Transmission Model Comparison
      • IGM Transmission vs Redshift
      • IGM Absorption Evolution with Redshift
    • Inference Methods
      • Convergence Diagnostics
      • Corner Plot with Truth Overlay
      • Population PSD Recovery: 1/√N Convergence
      • MAP vs geoVI Posterior Comparison
      • Population VI scaling: time, memory, and convergence
      • Prior vs Posterior: Parameter Constraints from Inference
    • Metallicity
      • α/Fe Enhancement (met_alpha_fe)
      • Metallicity Sweep: Panchromatic SED
      • Stellar Metallicity (log Z/Z_⊙)
      • Stellar Continuum: Metallicity × Age Grid
      • Chemical Evolution: Model Comparison
    • Multiwavelength
      • FIR–Radio Correlation
      • Panchromatic AGN Host SED
      • AGN Contribution to Composite SEDs
      • Dust Energy Balance: UV Attenuation ↔ IR Emission
      • Panchromatic Star-Forming Galaxy
      • Panchromatic SED: Redshift Evolution
    • Nebular Emission
      • BPT with Cue: Every Knob, One Panel Each
      • BPT Diagrams with Cue: 2D Grid in (log U, log Z_gas)
      • BPT Diagnostics: Star Formation, Shocks, and AGN
      • Diffuse Ionized Gas Fraction (f_DIG)
      • Ionizing Photon Escape Fraction (f_esc)
      • Emission Line Width (σ in km/s)
      • Ionization Parameter (logU)
      • Gas Metallicity (log Z/Zsun)
      • Nebular Emission: Dependence on Stellar Population Age
      • Nebular Backends: BakedIn vs CloudyGrid vs Cue
      • BPT Diagram: Ionization Parameter Sequence
      • Nebular Gas Density: Metallicity Variation
      • Nebular Emission Backends
      • Nebular Shock Emission (MAPPINGS V)
    • Photometry
      • SDSS Filter Transmission Curves
      • Filter Set Comparison
      • Photometric SED Fit
      • Filter Sampling Across Redshift
      • S/N Ratio Parameter Sweep
    • Quick Start
      • First Photometric Fit
      • SED Components
    • Radio
      • Radio Spectral Index (α_sf)
      • FIR-Radio Correlation (q_IR)
      • FIR-Radio Correlation: L_IR Luminosity Sweep
      • AGN Radio Loudness (R)
    • Star Formation Histories
      • SFH Recovery Across Four Burstiness Regimes
      • Chemical Evolution: Metallicity History Models
      • Delayed-τ SFH: Star Formation Timescale
      • Double Power-Law SFH: 2D Parameter Grid (α × β)
      • Double Power-Law SFH: Rising Slope α
      • Double Power-Law SFH: Falling Slope β
      • Log-Normal SFH: Peak Lookback Time
      • Parametric SFH Models
      • Alternative PSD Models
      • PSD Parameter Space and Burstiness
      • Stochastic SFH: Burstiness Amplitude σ
      • Stochastic SFH: Burstiness Timescale τ
      • SFH with Double Bursts: Old and Recent Star Formation
      • SFH Quenching Scenarios: Constant, Exponential, Sharp, and Burst+Decay
      • Stochastic SFH from GP Correlated Fields
      • The Wrong-SEDModel Trap: Parametric Bias in Derived Quantities
    • Spectroscopy
      • Instrumental Resolution Sweep
      • Key Spectral Features as Age and Metallicity Probes
      • Spectroscopic SED Fit
      • Stellar Velocity Dispersion Sweep
    • Stellar Population Synthesis
      • Stellar Population Aging: SSP at Solar Metallicity
      • SSP Grid Visualization: Age and Metallicity
      • IMF Comparison: Mass-to-Light Ratio
      • Stellar Metallicity Effects on SED
    • X-ray Emission
      • High-Energy Cutoff Variation
      • X-ray Normalisation via UV-to-X-ray Slope
      • AGN X-ray Emission and Corona
      • X-ray Spectral Index Variation
      • X-ray Binary Population from Star Formation
    • Examples gallery
    • Advanced Topics
    • AGN Models
    • Hensley & Draine 2023 Astrodust+PAH
    • Dust Models
    • IGM
    • Inference Methods
    • Metallicity
    • Multiwavelength
    • Nebular Emission
    • Photometry
    • Quick Start
    • Radio
    • Star Formation Histories
    • Spectroscopy
    • Stellar Population Synthesis
    • X-ray Emission
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Spectroscopy¶

Spectroscopic fitting and spectral features.

Instrumental Resolution Sweep

Instrumental Resolution Sweep

Key Spectral Features as Age and Metallicity Probes

Key Spectral Features as Age and Metallicity Probes

Spectroscopic SED Fit

Spectroscopic SED Fit

Stellar Velocity Dispersion Sweep

Stellar Velocity Dispersion Sweep
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Instrumental Resolution Sweep
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The Wrong-SEDModel Trap: Parametric Bias in Derived Quantities
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