One-Dimensional Spectrum

GEHONG provides physical models for simulating one-dimensional (1D) spectra of various astrophysical sources. These models are the building blocks for constructing spatially resolved 2D and 3D spectral datacubes.

Supported Components

GEHONG supports the following 1D spectral components:

• Stellar Continuum Based on user-defined star formation history (SFH) and chemical enrichment history (CEH), synthesized from SSP templates.

• Ionized Gas Emission Lines H II region spectra modeled using photoionization grids and scaled by star formation rate (SFR) or Hα luminosity.

• Active Galactic Nuclei (AGN) Including power-law continuum, broad-line region (BLR), narrow-line region (NLR), and Fe II templates.

• Individual Stars High-resolution theoretical spectra generated from stellar atmosphere grids, based on Teff, logg, and [Fe/H].

Subsections

Modeling of Single Spectrum

• Ionized Gas Emission Lines
  • Overview
  • Emission Line Generation
  • Template Selection
  • Velocity Broadening
  • Dust Attenuation
  • Redshift and Peculiar Velocity
  • SFR-Calibrated Mode
  • Output Spectrum
• Stellar Continuum Spectrum
  • Overview
  • Spectral Construction
  • Velocity Dispersion Broadening
  • Dust Attenuation
  • Redshift and Peculiar Velocity
  • Flux Calibration
  • Output
• Spectrum of AGN
  • Broad Line Region (BLR)
  • Narrow Line Region (NLR)
  • Power-law Continuum
  • Fe II Emission Blends
• Single Star Spectrum
  • Overview
  • Template Selection
  • Spectral Broadening
  • Dust Attenuation
  • Redshift and Doppler Shift
  • Flux Calibration
  • Output