# Glossary ## Within `coronagraphs.py` | Variable Name | Length | Unit | Meaning | User Editable | | ------------------------------- | ------------------------ | ------------- | ------------------------------------------------------------ | ------------- | | Istar | [npix, npix] | Dimensionless | Star intensity distribution (on-axis PSF) | No | | noisefloor | [npix, npix] | Dimensionless | Noise floor of the coronagraph | No | | photometric_aperture_radius | Scalar | λ/D | Photometric aperture radius | Yes | | psf_trunc_ratio | Scalar | Dimensionless | truncate the off-axis PSF at a threshold (thresh = psf_trunc_ratio * max(off-axis PSF)) | Yes | | photometric_aperture_throughput | [npix, npix, npsfratios] | Dimensionless | fraction of light entering the coronagraph that ends up within the photometric core of the off-axis (planet) PSF assuming perfectly reflecting/transmitting optics, where the core is the solid angle area `Omega` and is set by either `psf_trunc_ratio` or `photometric_aperture_radius`. | No | | omega_lod | [npix, npix, npsfratios] | (λ/D)² | Solid angle of the photometric aperture | No | | skytrans | [npix, npix] | Dimensionless | Sky transmission; the coronagraph’s performance when observing an infinitely extended source | No | | pixscale | Scalar | λ/D | Pixel scale of the coronagraph model | No | | npix | Scalar | Dimensionless | length of one side of the coronagraph model images (assuming a square) | No | | xcenter | Scalar | Pixel | X-coordinate of the image center | No | | ycenter | Scalar | Pixel | Y-coordinate of the image center | No | | bandwidth | Scalar | Dimensionless | Fractional bandwidth of coronagraph | Yes | | stellar_radius | Scalar | R_sun | stellar radius in solar radii | Yes | | stellar_angular_diameter_arcsec | Scalar | arcsec | angular diameter of the star | No | | npsfratios | Scalar | Dimensionless | Number of PSF truncation ratios (default 1) | No | | nrolls | Scalar | Dimensionless | Number of roll angles performed | Yes | | nchannels | Scalar | Dimensionless | Number of channels in coronagraph | Yes | | minimum_IWA | Scalar | λ/D | Minimum Inner Working Angle | Yes | | maximum_OWA | Scalar | λ/D | Maximum Outer Working Angle | Yes | | coronagraph_optical_throughput | [nlambda] | Dimensionless | Throughput for all coronagraph optics | Yes | | coronagraph_spectral_resolution | Scalar | Dimensionless | Spectral resolution of the coronagraph | Yes | | contrast | Scalar | Dimensionless | Noise floor contrast of coronagraph | Yes | | noisefloor_factor | Scalar | Dimensionless | Systematic noise floor factor | Yes | | noisefloor_PPF | Scalar | Dimensionless | Noise floor post-processing factor | Yes | | Tcore | Scalar | Dimensionless | Core throughput of coronagraph (used in ToyModel only, or if photometric_aperture_radius is specified for omega_lod calculation) | Yes | | TLyot | Scalar | Dimensionless | Lyot transmission of the coronagraph (used in ToyModel only) | Yes | | PSFpeak | Scalar | Dimensionless | Peak value of the off-axis PSF | No | ### A note on calculating `omega_lod`: The photometric aperture `omega_lod` can be calculated via two methods, and the user should specify either the `psf_trunc_ratio` or `photometric_aperture_radius` parameters to do so. - `photometric_aperture_radius` simply sets a radius for the photometric aperture, such that `omega_lod = \pi * (photometric_aperture_radius * (lambda/D))^2`, where `omega_lod` is the solid angle of the photometric aperture. - In contrast, `psf_trunc_ratio` is a more complex way of calculating the photometric aperture solid angle `omega_lod`, necessary because the off-axis PSF is not always going to be a perfect circle, and can be misshapen. In principle, this method takes an off-axis PSF and calculates `omega_lod` as all pixels in the PSF that are above the threshold `psf_trunc_ratio * max(off-axis PSF)`, accounting for imperfect PSF shapes. Note: If the off-axis PSF shape is a perfect airy disk, then `psf_trunc_ratio` is simply `1 - photometric_aperture_radius`. - Finally, `photometric_aperture_throughput` is an entirely different, but related, parameter, not to be confused with the two parameters above. This parameter is essentially the core throughput of the off-axis PSF. In other words, this is the fraction of light entering the coronagraph that ends up within the photometric core of the off-axis (planet) PSF assuming perfectly reflecting/transmitting optics, where the core is the solid angle area `omega_lod` and is set by either `psf_trunc_ratio` or `photometric_aperture_radius`. ## Within `telescopes.py` | Variable Name | Length | Unit | Meaning | User Editable | | -------------------- | --------- | ------------- | --------------------------------------------- | ------------- | | diameter | Scalar | m | Circumscribed diameter of telescope aperture | Yes | | Area | Scalar | m^2 | Effective collecting area of telescope | No | | unobscured_area | Scalar | Dimensionless | Unobscured area percentage | Yes | | toverhead_fixed | Scalar | Time | Fixed overhead time | Yes | | toverhead_multi | Scalar | Dimensionless | Multiplicative overhead time | Yes | | telescope_optical_throughput | [nlambda] | Dimensionless | Optical throughput of telescope | Yes | | temperature | Scalar | Temperature | Temperature of the warm optics | Yes | | T_contamination | Scalar | Dimensionless | Effective throughput factor for contamination | Yes | ## Within `detectors.py` | Variable Name | Length | Unit | Meaning | User Editable | | --------------- | --------- | --------------------------- | ------------------------------------------------- | ------------- | | pixscale_mas | Scalar | Milliarcsecond | Detector pixel scale | Yes | | npix_multiplier | [nlambda] | Dimensionless | Number of detector pixels per image plane "pixel" | Yes | | DC | [nlambda] | Electron / (Pixel * Second) | Dark current | Yes | | RN | [nlambda] | Electron / (Pixel * Read) | Read noise | Yes | | tread | [nlambda] | Second | Read time | Yes | | CIC | [nlambda] | Electron / (Pixel * Photon) | Clock-induced charge | Yes | | QE | [nlambda] | Electron / Photon | Quantum efficiency of detector | Yes | | dQE | [nlambda] | Dimensionless | Effective QE due to degradation | Yes | ## Within `observation.py` | Variable Name | Length | Unit | Meaning | User Editable | | --------------- | --------- | ------------- | --------------------------------------- | ------------- | | wavelength | [nlambda] | um | Observation wavelengths | Yes | | SNR | [nlambda] | Dimensionless | Signal-to-noise ratio | Yes | | CRb_multiplier | Scalar | Dimensionless | Factor to multiply assuming differential imaging to remove background | Yes | | td_limit | Scalar | s | Limit placed on exposure times | No | | exptime | [nlambda] | s | Exposure time for each wavelength | No | | fullsnr | [nlambda] | Dimensionless | Calculated SNR for each wavelength | No | | observing_mode | Scalar | String | Observing mode (e.g., 'IMAGER' or 'IFS') | Yes | ## Within `astrophysical_scene.py` | Variable Name | Length | Unit | Meaning | User Editable | | ----------------------- | --------- | ---------------------------- | ------------------------------------------------- | ------------- | | dist | Scalar | pc | Distance to star | Yes | | vmag | Scalar | Magnitude | Stellar magnitude at V band | Yes | | mag | [nlambda] | Magnitude | Stellar magnitude at desired wavelengths | Yes | | stellar_angular_diameter_arcsec | Scalar | Arcsecond | Angular diameter of star | No | | nzodis | Scalar | Zodi | Amount of exozodi around target star | Yes | | ra | Scalar | Degree | Right ascension of target star | Yes | | dec | Scalar | Degree | Declination of target star | Yes | | semimajor_axis | Scalar | Astronomical Units | Semimajor axis of the planet's orbit (used to calculate separation; assumes face-on orbit) | Yes | | separation | Scalar | Arcsecond | Separation of planet | Yes | | xp | Scalar | Arcsecond | X-coordinate of planet (defaults to zero for now) | No | | yp | Scalar | Arcsecond | Y-coordinate of planet | No | | deltamag | [nlambda] | Magnitude | Magnitude difference between planet and host star | Yes | | min_deltamag | [nlambda] | Magnitude | Brightest planet to resolve at the IWA | Yes | | F0V | Scalar | Photon / (s * cm² * nm) | Flux zero point for V band | Yes | | F0 | [nlambda] | Photon / (s * cm² * nm) | Flux zero points for prescribed wavelengths | Yes | | M_V | Scalar | Magnitude | Absolute V band magnitude of target star | No | | Fzodi_list | [nlambda] | Dimensionless | Zodiacal light fluxes | No | | Fexozodi_list | [nlambda] | Dimensionless | Exozodiacal light fluxes | No | | Fbinary_list | [nlambda] | Dimensionless | Binary star fluxes | No | | Fp_over_Fs | [nlambda] | Dimensionless | Flux of planet relative to star | Yes | | Fs_over_F0 | [nlambda] | Dimensionless | Stellar flux relative to F0 | No | ## Within `observatory.py` | Variable Name | Length | Unit | Meaning | User Editable | |---------------|--------|------|---------|---------------| | optics_throughput | [nlambda] | Dimensionless | Optical throughput of the entire system | Yes* | | epswarmTrcold | [nlambda] | Dimensionless | Warm emissivity * cold transmission factor | Yes* | | total_throughput | [nlambda] | Dimensionless | Total throughput including optics and detector | No | ## Within `parse_input.py` | Variable Name | Length | Unit | Meaning | User Editable | | ------------------ | ------ | ------- | ---------------------------------------- | ------------- | | secondary_flag | Scalar | Boolean | Flag for secondary variables | Yes | | observatory_preset | Scalar | String | Preset configuration for the observatory | Yes | | telescope_type | Scalar | String | Type of telescope to use | Yes | | coronagraph_type | Scalar | String | Type of coronagraph to use | Yes | | detector_type | Scalar | String | Type of detector to use | Yes | | observing_mode | Scalar | String | Observing mode (e.g., 'IMAGER' or 'IFS') | Yes | ## Within `exposure_time_calculator.py` | Variable Name | Length | Unit | Meaning | User Editable | | ---------------- | ------ | ------------- | --------------------------------------------------- | ------------- | | deltalambda_nm | Scalar | nm | Bandwidth for each wavelength | No | | lod | Scalar | Dimensionless | λ/D (wavelength / telescope diameter) | No | | lod_rad | Scalar | Radian | λ/D in radians | No | | lod_arcsec | Scalar | Arcsecond | λ/D in arcseconds | No | | area_cm2 | Scalar | cm² | Telescope collecting area | No | | detpixscale_lod | Scalar | λ/D | Detector pixel scale in λ/D units | No | | stellar_diam_lod | Scalar | λ/D | Stellar diameter in λ/D units | No | | det_sep_pix | Scalar | Pixel | Separation at IWA in pixels | No | | det_sep | Scalar | Arcsecond | Separation at IWA in arcseconds | No | | det_Istar | Scalar | Dimensionless | Max stellar intensity at IWA | No | | det_skytrans | Scalar | Dimensionless | Max sky transmission at IWA | No | | det_photometric_aperture_throughput | Scalar | Dimensionless | Max photometric aperture fraction at IWA | No | | det_omega_lod | Scalar | (λ/D)² | Solid angle corresponding to max photometric_aperture_throughput at IWA | No | | det_npix | Scalar | Pixel | Number of pixels in detector | No | | CRp | Scalar | Electron/s | Planet count rate | No | | CRbs | Scalar | Electron/s | Stellar leakage count rate | No | | CRbz | Scalar | Electron/s | Local zodiacal light count rate | No | | CRbez | Scalar | Electron/s | Exozodiacal light count rate | No | | CRbbin | Scalar | Electron/s | Binary star count rate | No | | CRbth | Scalar | Electron/s | Thermal background count rate | No | | CRbd | Scalar | Electron/s | Detector noise count rate | No | | CRnf | Scalar | Electron/s | Noise floor count rate | No | | CRb | Scalar | Electron/s | Total background count rate | No | | t_photon_count | Scalar | s | Photon counting time | No |