Spectral Overlap Files (SOF) – ExoPhot Project

Spectral Overlap Files (SOF) – ExoPhot Project

These Spectral Overlap Files (SOF) provide data on the spectral absorption rate (Γλ), which quantifies the number of photons absorbed per unit time and wavelength by a given photopigment in an exoplanetary environment. The calculation is based on the overlap between the stellar spectral flux density at the top of the exoplanet atmosphere (Fλ), the atmosphere transmittance (T), and the photopigment absorption cross-section (σ_abs).

These files are part of the ExoPhot project, which investigates the feasibility of photosynthetic activity on exoplanets orbiting different types of stars by evaluating the interaction between stellar radiation, planetary atmospheres, and photosynthetic pigments (both terrestrial and theoretical).

Contents of the SOF Files

Each SOF file includes the following parameters:

General Information

Date – Date of file generation

SED File – Stellar Spectral Energy Distribution file used

Atmosphere File – Atmospheric model file used

Photopigment File – Photopigment absorption data file used

Stellar Radius (Rs, km) – Radius of the host star

Exoplanet Orbit Semi-Major Axis (sma, km) – Distance between the exoplanet and the host star

Total Absorption Rate (γ_t, s⁻¹) – Overall photon absorption rate across all wavelengths

B Band Absorption Rate (γ_B, s⁻¹) – Absorption rate in the B band

Q Band Absorption Rate (γ_Q, s⁻¹) – Absorption rate in the Q band

B-Q Bands Cut-off (nm) – Wavelength division between B and Q bands

Photosynthetic Photon Flux Density (PPFD, μmol photon m⁻² s⁻¹) – Number of photons available for photosynthesis per unit area and time

Total Stellar Irradiance (S, W m⁻²) – Total incoming stellar energy per unit area

Spectral Data Columns

Col 1: Wavelength (wl, Å) – Wavelength of incident radiation

Col 2: Spectral Flux Density (Fλ, J cm⁻² s⁻¹ Å⁻¹) – Stellar flux at the top of the exoplanet’s atmosphere

Col 3: Atmosphere Transmittance (T, unitless) – Fraction of stellar radiation transmitted through the exoplanet’s atmosphere

Col 4: Pigment Absorption Cross Section (σ_abs, cm²) – Absorption efficiency of the photopigment

Col 5: Spectral Absorption Rate (Γλ, Å⁻¹ s⁻¹) – Rate of photon absorption per unit wavelength

These datasets are intended for use by the scientific community to analyze potential photosynthetic activity under different stellar and atmospheric conditions. The SOF files can support research in astrobiology, exoplanet habitability, and comparative planetology.

For more details, refer to the ExoPhot project documentation at Github or the following publications:

P. Marcos-Arenal, et al., ExoPhot: The photon absorption rate as a new metric for quantifying the exoplanetary photosynthetic activity fitness, Universe 8(12), 624 (2022)

J. García de la Concepción, et al., Phot0, a plausible primeval pigment on earth and rocky exoplanets, Phys. Chem. Chem. Phys., 24, 16979-16987 (2022)